vegan diet essay

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The Impact of a Vegan Diet on Many Aspects of Health: The Overlooked Side of Veganism

1 Internal Medicine / Nephrology, Geisinger Health System, Wilkes-Barre, USA

2 Medicine, Geisinger Commonwealth School of Medicine, Scranton, USA

3 Medicine, Geisinger Medical Center, Danville, USA

4 Internal Medicine, Geisinger Health System, Wilkes-Barre, USA

Vegetarianism in any of its various forms, particularly veganism, has been increasing in popularity over the past few years, especially among the young population in the United States. While several studies have shown that a vegan diet (VD) decreases the risk of cardiometabolic diseases, such as cardiovascular disease, type 2 diabetes mellitus, obesity, and non-alcoholic fatty liver disease, veganism has been associated with adverse health outcomes, namely, nervous, skeletal, and immune system impairments, hematological disorders, as well as mental health problems due to the potential for micro and macronutrient deficits. The goal of this review article is to discuss the current literature on the impact and long-term consequences of veganism on vulnerable populations, including children, adolescents, pregnant and breastfeeding women, and fetal outcomes in strict vegan mothers. It also focuses on the many deficiencies of the vegan diet, especially vitamin B12, and the related increased risk of malignancies.

Introduction and background

Vegetarianism in various forms has gained widespread popularity in recent years. These types include vegans, who adhere to the most stringent dietary restrictions, omitting all animal-source foods and their by-products from the diet. Others include lactovegetarians (no meat, fish, or eggs but do consume dairy goods), ovo-vegetarians (no meat, fish, or dairy products but do consume eggs), lacto-ovo-vegetarians (no meat but do consume eggs and dairy products), and pescatarians (no meat except fish and shellfish) [ 1 , 2 ]. There has been growing interest in dietary habits given the worsening obesity epidemic and obesity-related health concerns [ 3 , 4 ]. Obesity is an established risk factor for diabetes mellitus, which, in turn, is an independent risk factor for coronary artery disease [ 5 ]. While studies have shown that a vegan diet (VD) may be associated with improved health outcomes [ 6 , 7 ], the negative health repercussions of these food preferences, on the other hand, are rarely highlighted, and veganism may be associated with negative health effects due to nutritional deficiencies.

Additionally, vegans have a greater prevalence of mental health problems, which may lead to a poorer quality of life. An optimal diet should be balanced, consisting of lean meat, nuts, fresh fruits and vegetables, and olive oil (Figure ​ (Figure1) 1 ) [ 8 , 9 ]. A wholesome diet is essential in maintaining a healthy gut flora, which in turn is pivotal in avoiding inflammatory disorders [ 10 - 13 ]. The primary aim of this review will be to draw attention to the current literature associated with veganism, including the side effects of practicing a VD and long-term consequences for a variety of populations, including adults, adolescents, pregnant and lactating women, and the fetal outcomes of vegan mothers.‬‬‬‬‬‬

A recent systematic study examined the intake and adequacy of the VD in terms of macro and micronutrient intake in the adult European population. The study found that vegans consumed the least total protein compared to other diet groups, confirming concerns that VD may include insufficient protein, particularly in instances where legume, seed, and nut consumption is limited [ 14 ]. Vegans consume fewer essential amino acids than non-vegans [ 15 ]. Plant proteins are less digestible (50-70%) than animal proteins, and food processing methods like heating may further reduce digestibility. According to the WHO, animal proteins are considered complete proteins and have higher biological value, protein efficiency ratio, net protein utilization, and, ultimately, have a higher Protein Digestibility Corrected Amino Acid Score (PDCAAS) compared to plant proteins [ 16 , 17 ]. By and large, soy proteins constitute a significant protein source for most vegans [ 18 ].

Vitamin B12

Low vitamin B12 intake is a significant problem in vegan diets due to the exclusion of vitamin B12-rich foods such as meat, poultry, and eggs. A lack of vitamin B12 has been linked to neurologic and hematologic problems [ 19 ]. Low vitamin B12 intake has serious clinical consequences, although deficient symptoms appear gradually over time. High folate levels may also partly and temporarily obscure some of the typical vitamin B12 hematological manifestations. To prevent vitamin B12 deficiency, vegans must get their levels checked regularly and meet their daily requirements via supplements or fortified foods.

A growing body of research indicates that inadequate B12 consumption may contribute to carcinogenesis. Vitamin B12 deficiency increases uracil misincorporation, impairing DNA synthesis and genomic instability. Global hypomethylation of DNA is a characteristic of early carcinogenesis. Thus, if not adequately replaced, VD may inadvertently lead to cancers [ 20 ]. Wu et al found that blood B12 levels were substantially lower in menopausal and postmenopausal breast cancer patients, and patients with the lowest B12 levels had an elevated risk of breast cancer [ 21 ]. Reduced B12 levels have also been linked to an increased risk of cervical and gastrointestinal tract malignancies [ 22 - 24 ]. As a result, B12 supplementation is imperative for vegans due to the extensive and irreversible detrimental effects of the deficiencies.

Other minerals and micronutrients

Vegans have greater iron needs than other diet patterns [ 25 ], mainly because non-heme iron from plant-based foods is less bioavailable, as absorption is hindered by whole grains, legumes, and nuts due to their phytic acid content [ 26 ]. Vegans also have a zinc deficit. While meat, dairy, and eggs contain zinc, some zinc-rich plant foods (e.g., nuts, seeds, and whole grains) have poor bioavailability owing to the presence of phytate, which inhibits absorption in the gut [ 16 ]. Inadequate zinc consumption may be associated with mental health problems (e.g., depression), dermatitis, diarrhea, and alopecia, all of which are more prevalent among vegans [ 27 , 28 ]. Selenium insufficiency has also been seen among vegetarians.

Vitamin D, calcium, bone mineral density, and risk of fractures

Numerous studies have shown that vegans consume insufficient calcium and vitamin D, not only owing to the absence of dairy products but also due to calcium bioavailability problems in plant-based diets [ 28 ]. Vitamin D insufficiency exacerbates calcium shortage further owing to impaired intestinal absorption. After adjusting for socioeconomic variables, lifestyle covariates, and body mass index (BMI), a recent study reported that as compared to meat-eaters, there was an increased risk of hip fractures observed in vegetarians (HR 1.25; CI 1.04-1.50), vegans (2.31; 1.66-3.22), and fish eaters (1.26; 1.02-1.54) [ 29 ]. Vegans also had a greater incidence of overall fracture (1.43; 1.20-1.70), leg fractures (2.05; 1.23-3.41), and fractures in other major sites (1.59; 1.02-2.50). The higher risk of fractures may be related to vegans' significantly lower calcium intake, reduced dietary protein intake, and lower BMI [ 30 - 32 ].

Mental health

The most recent systematic review [ 33 ], which included eighteen studies, compared meat abstainers versus meat eaters in terms of mental health. The research included 160,257 individuals (85,843 females and 73,232 men) from various geographic areas, including 149,559 meat eaters and 8584 meat abstainers (aged 11 to 96 years). Eleven of the 18 studies found that meat-free diets were linked with worse psychological health, four were inconclusive, and three found that meat-free diets resulted in improved results. The most thorough research found that meat-avoiders (i.e., "full vegetarians") had a 7.4%, 24.1 %, and 35.2% 1-month, 12-month, and lifetime prevalence of unipolar depressive disorders, respectively. In contrast, meat consumers had a much lower prevalence: 6.3%, 11.9%, and 19.1%. Similarly, the 1-month, 12-month, and lifetime prevalence of anxiety disorders for meat abstainers were much higher at 20.4%, 31.5%, 31.5%, and 10.7%, 17.0%, and 18.4% in the meat eaters respectively. The study highlights the high incidence of mental health problems among vegans, emphasizing the vital need of increasing awareness of these illnesses to facilitate early intervention. Women notably appeared to be adversely impacted by mental disorders such as stress [ 34 - 36 ].

Orthorexia nervosa (ON) is defined as a fixation on health-conscious eating behavior [ 37 ]. It involves obsessive (compulsive) food decisions, self-imposed anxiety, self-punishment, and increasingly extreme limitations. As a result of diet-related concerns, individuals develop dietary restrictions, lack of food pleasure, inflexible and rigid eating behaviors, and ritual activities surrounding food preparations. Vegetarian, and vegan, women are more prone than males to have disordered eating attitudes and practices [ 38 ].

Although some studies indicate a reduction in mortality associated with vegetarianism and VD, the larger body of evidence indicates that the health benefits associated with vegetarianism may be due to other “lifestyle” factors associated with socioeconomic statuses, such as adequate physical activity, low alcohol, and drug consumption, or avoidance of tobacco products. Recently, Johnston et al. argued that the evidence supporting public health recommendations to reduce or eliminate meat intake was based on questionable studies and "inappropriate analysis" [ 39 ]. This argument and the growing body of contrasting and conflicting findings create a conundrum for doctors and policymakers alike.

Effects on children and adolescents

Adolescents are also known to show a strong preference for VD. A balanced diet is critical for children and adolescents to meet their bodies' rising demands during the growth spurt, rendering the implications of VD in this vulnerable age more intriguing. A recent study examined the anthropometry, dietary intakes, and nutritional status of 149 vegetarians, 115 vegans, and 137 omnivore children and adolescents using a cross-sectional design (6-18 years old, mean age: 12.7 ± 3.9 years) [ 40 ]. Vegetarians and vegans consumed more carbohydrates than omnivores (p = 0.0002). Vegetarians (p = 0.02) had the lowest protein consumption, however, vitamin B2, D3, HDL-C, and triglyceride blood concentrations did not differ between diet groups. The authors concluded that there are no specific nutrient concerns among vegetarian, vegan children and adolescents compared to omnivores. The study's cross-sectional design and lack of representativity should be considered when interpreting the findings.

In contrast to the above study, subsequent cross-sectional studies showed that vegetarian and/or vegan children had a lower bone mineral density (BMD) [ 41 , 42 ]. Desmond et al. observed that vegetarians and vegans were shorter than omnivores (-0.32 and -0.57 height z scores, respectively), but the difference was non-significant in vegetarians [ 42 ]. The research showed that after controlling for body size, vegan children had substantially lower vitamin D levels and BMD than omnivores. It is suggested to maximize childhood BMD to promote peak BMD and therefore reduce the risk of osteoporosis and fracture in adulthood. The authors concluded that vegans had lower BMDs even when body and bone size were taken into consideration. It does not seem to be ideal to start puberty, a period when bone-specific nutrition requirements are greater, with an already established BMD deficiency. If such deficiencies continue throughout adolescence as a result of a diet, they may raise the likelihood of poor bone outcomes later in life. Prospective longitudinal studies are required to better understand the consequences of VD on children and adolescents.

Effects on pregnancy, fetal outcomes, and lactation

Optimal fetal growth requires balanced maternal nutrition during pregnancy. Mothers on rigorous VD are at risk of vitamin insufficiency, which can lead to poor fetal outcomes. A recent study included 273 women, including 112 omnivores, 37 fish eaters, 64 lacto-ovo-vegetarians, and 60 vegans, respectively [ 43 ]. In comparison to an omnivorous diet, the vegan diet was substantially linked with an elevated risk of small-for-gestational-age infants (RR = 5.9, 95 percent CI, 1.2-21.8). All the groups had a similar incidence of preterm births. Birthweight in vegans was lower compared to lacto-ovo-vegetarians (3015 ± 420 g vs. 3285 ± 482 g, P = 0.004) and to omnivores (3328 ± 495 g, P < 0.001) but not to fish-eaters. Vegans also had a lower mean gestational weight gain compared only to omnivores (11.6 ± 4.2 kg vs. 14.3 ± 4.6 kg, P = 0.001). A review of 13 low and middle-income nations found low docosahexaenoic acid levels in breast milk in mothers on plant-based diets but greater in the fish-eating population [ 44 ].

Maternal B12 status influences their offspring’s B12 levels and is an independent risk factor for neural tube defects (NTD) [ 45 ]. Studies have shown an association between low B12, low birth weight, and pre-term delivery [ 46 ]. A Chinese study associated increased maternal pickled vegetable consumption with NTD due to excessive nitrate, nitrite, and N-nitroso compound content [ 47 ]. They found that eating pickled vegetables more frequently (>6 meals/week) increased the risk of NTD. The investigators also found that maternal consumption of meat, eggs, or milk (>1 meal/week) reduced the risk of NTD. Vegan mothers may have poor prenatal nutritional status, resulting in low maternal fat reserves for breastfeeding. The postpartum nutritional profile of vegetarian mothers declines without sufficient energy intake, thus maternal nutritional reserves are lost to promote infant normal development. 

Providers should evaluate a woman's nutrition and energy consumption frequently. Women on restrictive diets may need to take supplements or eat fortified foods to meet the required needs throughout pregnancy and breastfeeding. Plant-based diets during pregnancy and breastfeeding need a heightened awareness of the importance of consuming all necessary nutrients and vitamin supplements, as recommended by international guidelines [ 48 ].

Conclusions

While veganism has been shown to decrease the risk of cardiovascular and metabolic syndrome, it also carries the potential for micro- and macronutrient deficits. It should be noted that vegans often have better socioeconomic levels, live a healthier lifestyle with more physical exercise, and tend to smoke less compared to non-vegetarians, making it difficult to isolate the effects of veganism in observational research. Existing research is often skewed by selection bias, which is when the study sample is chosen based on prior eating patterns and such studies are often recruited in environments with a high level of health awareness. Our review focuses on the impact of veganism on vulnerable populations, including children, adolescents, pregnant and breastfeeding women, and fetal outcomes in strict vegan mothers. Vegans should be closely monitored and treated for nutritional deficiencies, in order to mitigate any long-term negative health outcomes. Given the growing interest in diets without animal protein intake in the general population, it is crucial, now more than ever, to have a clear understanding of both the risks and benefits of such diets among clinicians, policymakers, and the public.

The content published in Cureus is the result of clinical experience and/or research by independent individuals or organizations. Cureus is not responsible for the scientific accuracy or reliability of data or conclusions published herein. All content published within Cureus is intended only for educational, research and reference purposes. Additionally, articles published within Cureus should not be deemed a suitable substitute for the advice of a qualified health care professional. Do not disregard or avoid professional medical advice due to content published within Cureus.

The authors have declared that no competing interests exist.

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Healthy Eating

Plant-based diets are best… or are they?

People choose a vegetarian or vegan diet for a number of reasons. Sometimes it's out of concern for the way animals are treated or for the environment. But it's also common to choose a plant-based diet because it's considered healthier.

And that's for good reason. Research over many years has linked plant-based diets to lower rates of heart disease, type 2 diabetes, and some cancers (as compared with diets high in meat and other animal products). Dietary guidelines and recommendations from nutrition experts reflect this, encouraging the adoption of diets (such as the Mediterranean diet and the DASH diet ) that are heavy on fruits and vegetables and restrict consumption of red meat.

Popular plant-based diets include

• a vegetarian diet, which includes no meat
• a vegan diet, a type of vegetarian diet that excludes not just meat but also animal products, such as milk or eggs
• a pescatarian diet, which is largely vegetarian but also includes seafood.

Plant-based diets carry some risk of inadequate protein, vitamin, and mineral intake. But these risks are readily overcome by choosing the right vegetarian foods and, when necessary, supplements. For example, soy, quinoa, and nuts are good sources of protein, and tofu, lentils, and spinach are good sources of iron.

But a new study , published in the medical journal The BMJ , raises the possibility that despite the health benefits demonstrated by past research, plant-based diets could come with a previously unrecognized health risk.

Vegetarians and vegans may have an increased risk of stroke

Researchers in the United Kingdom analyzed the risk of stroke and other health problems over two decades among nearly 50,000 people based on the diets they followed. The types of stroke were also analyzed, including bleeding into the brain (hemorrhagic stroke) and nonbleeding stroke (ischemic stroke). Compared with meat eaters:

• rates of heart disease (such as angina or heart attack) were 13% lower in pescatarians
• rates of heart disease were 22% lower in vegetarians
• rates of stroke were 20% higher among vegetarians. However, the overall risk was small, equal to three extra cases per 1,000 people over 10 years.
• the higher stroke risk among vegetarians was mostly due to hemorrhagic stroke
• the higher stroke risk was not observed among pescatarians.

If confirmed, these findings will complicate the way we look at plant-based diets. Are there serious and underappreciated downsides to these diets that should make us think twice about choosing them? Or is the increased risk of stroke heavily outweighed by cardiac and other health benefits?

This study is also a reminder that the health impact of a particular intervention (such as diet) may not be easy to predict or explain. In most cases, the risk of stroke and heart disease tend to rise or fall together, but that wasn't the case in this research.

Beware the study's limitations

This study linking a vegetarian diet with a higher risk of hemorrhagic stroke has a number of important limitations that should temper the concerns of vegetarians.

• The study was observational. That means it simply observed what happened among different people who followed different diets over time, without being able to account for every other relevant factor. For example, if vegetarians chose plant-based diets because of a family history of stroke, it could be their genes driving the higher rates of stroke, not the diet.
• The findings might have been different if the study had included a different study population, such as one with different genetic backgrounds or higher rates of obesity.
• The data regarding diet was self-reported. While the use of dietary surveys is common and necessary in research that requires a large number of study subjects, it isn't always reliable.
• The study was not large enough to reliably sort out differences in the rates of disease between vegans and vegetarians. As a result, it's not clear whether the increased stroke risk applies to all vegetarians, or whether vegans might have a different risk.
• We don't know whether the health outcomes reported in this study might be due to what is included in the diet or what is eliminated. For example, is the lower risk of heart disease among vegetarians due to the plant-based diet, or is it just due to the restriction of animal-based products?

Even so, the results are worthy of our attention — and future study.

The bottom line

If the findings of this new research stand the test of time (and future study), a key question will be: how does a vegetarian diet increase the risk of stroke? Understanding how one's diet impacts the risk of stroke and other disease will be crucial in future dietary recommendations and other preventive measures and treatments.

About the Author

Robert H. Shmerling, MD , Senior Faculty Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing

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Pros and Cons of a Vegan Diet

Verywell / Alexandra Shytsman

A vegan diet is a vegetarian eating style, but it's completely devoid of animal products, including eggs , honey, and dairy products. Some vegans choose the diet for health reasons, but others prefer it for ethical reasons, such as avoiding animal cruelty and consuming more sustainable foods.

While there are documented health benefits of a vegan diet, some find the lifestyle challenging to maintain. Consider each of the pros and cons of a vegan diet before you decide if it is the right program for you.

Evidence-based health benefits

Encourages mindful eating

Wider variety of foods

May lead to weight loss

Reduced food costs

Healthier for the environment

No animal impact

Limited food choices

Possible nutrient deficiencies

Requires diligence

Difficulty dining out

Unrealistic expectations

Social isolation

The reason (or reasons) that you choose a vegan eating plan will determine the benefits that are most relevant for you. But advantages to this lifestyle are substantial, regardless of whether you are choosing it for health, environmental, or ethical reasons.

Health Benefits

Since a vegan diet is plant-based , it's easier to load up on healthy whole grains , legumes, fruits, and vegetables that many people on regular diets lack. Studies comparing different types of diets have found that vegan eating ranks highest for nutritional quality. A vegan diet is generally high in fiber, vitamin C , magnesium, iron, and folate and lower in calories and saturated fats.​

The nutritional quality of a vegan diet leads to more significant health benefits. Eating a diet rich in plant-based foods has been associated with a decreased risk of many chronic diseases. A large cohort study evaluated vegetarian and vegan diets. Researchers found that both groups experienced a reduced risk of cardiovascular diseases, cardiometabolic risk factors, some cancers, and total mortality. Those who were vegan enjoyed those benefits along with a reduced risk of obesity, hypertension, type-2 diabetes, and cardiovascular mortality.

Other studies have confirmed those findings and have also found that plant-based eating may be helpful in the treatment and management of high blood pressure, diverticular disease, and eye cataracts.

Mindful Eating

Mindful eating is a practice that involves paying more attention to our food and increasing sensual awareness and experience of a meal. It requires the eater to be focused intentionally on eating behavior to enjoy the process of eating rather than any specific nutritional outcome ( calories , protein, fat, carbohydrates). Mindful eating practices are associated with a healthier relationship with food and have been used in some weight-loss interventions.

Vegan eating and mindful eating are different. But because vegan eaters—unlike omnivores—choose to eliminate certain categories of food from their diet, they need to be more selective and conscious about their food choices. In many cases, certain mindful eating practices are built into their meal planning .

For example, if you consume a traditional American diet, it is easy to grab a meal on the go at a fast-food restaurant, convenience mart, or coffee shop. It is easy to consume the meal without being fully aware of the eating process (i.e.chewing, tasting, and feeling a sense of fullness). But on a vegan diet, you may have to plan meals in advance to find foods that you enjoy and that are compliant on the eating plan. Or you may have to make careful selections in the moment. The choosing and planning process requires consideration, focus, and thoughtfulness about your food choices—critical components of mindful eating.

Wider Food Variety

An omnivore diet eliminates no foods. The standard American diet is an omnivore diet. But most people who consume a traditional diet eat a relatively limited number of foods or types of food. For instance, many traditional American dinners include meat, starch (potato or rice), and maybe a vegetable. Dairy products are often used as ingredients, side dishes, or toppings.

On a vegan diet, however, many traditional foods are not compliant. Therefore, when you begin this diet, you may have to get creative and experiment with foods that are not familiar.

But there is a caveat to this benefit. Many food manufacturers are creating plant-based versions of traditional favorites. For instance, most grocery stores carry vegan-friendly meatless burgers, processed chicken or turkey alternatives, and dairy substitutes that are made from soy or other ingredients. Sometimes, these products are no healthier than their meat/dairy alternative, and relying on them can lead to the same limited food palate like a traditional American diet.

Possible Weight Loss

Studies have shown that you may lose weight on a vegan diet. Of course, just choosing to go vegan does not cause weight loss to occur. But when you adopt this lifestyle, you eliminate many foods that are high in fat and calories.

Plant-based eating is often associated with losing weight. In 2018, a limited 16-week clinical trial found that a vegan diet proved to be superior to a control diet (that included animal protein) in improving body weight and fat mass. And a broad evidence review published in 2017 found that plant-based diets are an effective tool in the management and prevention of overweight and obesity.

Even if you have problems staying on a weight loss plan, a vegan lifestyle might be the best choice. Studies have also shown that a vegan eating plan may be more effective for weight loss , even if you don't completely stick to the program.

Reduced Food Costs

Choosing a vegan diet may help you to reduce your food costs. But whether or not you gain this benefit depends on what you eat before adopting this eating style and what you choose to eat after.

There is no doubt that meat, seafood, and dairy products are expensive. Some convenience foods can also be pricey. When you remove these foods from your diet, you eliminate the substantial food costs that are associated with them.

Vegan-friendly-grains and legumes are usually budget-friendly. And even though fresh produce and vegan-friendly convenience foods can be expensive, they are likely to cost less overall than a diet rich in animal-based products.

Better for the Environment

Some people choose a vegan diet because they feel it is better for the planet. There is increased concern in the environmental community about the impact of livestock and livestock farming practices on the earth.

By comparison, the farming of vegan-friendly plants requires fewer resources (land and water) than the production of typical western foods such as meat, poultry, and dairy. And cows produce more greenhouses gasses (methane) than plants do, which leads some to believe that eating vegan helps to reduce the risk of global warming.

Several research studies have even suggested that a vegan diet is better for the planet than other diets, including the popular Mediterranean diet .

No Animal Impact

Because no animals are harmed or killed to produce vegan-friendly foods, many choose this diet because of concerns about animal cruelty.

One study showed that the most popular reason for choosing a vegan diet is to support the more humane treatment of animals.   These vegans may also avoid clothing or other products that are made from animals, poultry, fish, or bees.

Interestingly, another research  study  published in the journal  Appetite  found that people who chose a vegan diet for ethical reasons were likely to stick to the diet longer than those who follow the program for other reasons.   

Even though a vegan diet may be healthier for you and the planet, this program doesn't work for everyone. Consider these drawbacks.

Limited Food Choices

The vegan diet is often referred to as the most restrictive version of a plant-based diet. Certainly, if you adopt this eating plan, and you currently eat a standard American diet, you can expect to eliminate most foods from your typical weekly menu. For some people, that level of restriction is too severe.

To get a greater sense of the scope of the restriction, remember that not only are animal products eliminated, but any food or product that contains an animal by-product is eliminated. Many traditional home recipes, groceries, and restaurant foods contain at least one animal by-product.

Of course, many vegans will tell you that there is a wealth of food variety in this diet. But because it varies substantially from what you might be used to eating, you may find it to be limiting at first.

Possible Nutritional Deficiencies

A vegan diet can be healthy, but there are a few potential nutritional deficiencies that need to be addressed. Researchers have found that vegan diets are generally lacking in calcium, required for bone formation, muscle contraction, and other essential functions. Vegans can increase their intake by eating calcium-rich foods such as green leafy vegetables, pulses, sesame seeds, some dried fruits, and calcium-fortified foods such as plant milks, non-milk yogurt, or cereal with calcium added. Similarly, they can supplement their diet with multivitamins .

Vitamin B-12 , or cobalamin, is another nutrient that may be lacking because it's found primarily in foods of animal origin. Vitamin B-12 is needed for healthy nerve function and blood cell production. A deficiency can lead to a condition called pernicious anemia . Although some seaweed, mushrooms, and fermented foods can be a useful source of this essential B-complex vitamin, researchers have found that vitamin B-12 supplementation may be needed for people who follow a vegetarian or vegan diet.

Protein can be another issue, but it's one that is easily solved. Proteins are made up of building blocks called amino acids that your body needs to maintain organs and muscles and important functions. Essential amino acids are those that your body does not make so you need to get them from the foods you eat. Many vegans also take creatine supplements .

While animal proteins contain all of the essential amino acids, plant proteins are usually missing one or more of those amino acids. So, it's crucial to eat a variety of protein sources to ensure you get all those amino acids you need.

Vegan diets can also be low in vitamin D , though to be fair, so are other diets since most of your vitamin D comes from exposure to sunlight. Two potentially good vegan sources of vitamin D include maitake mushrooms and portobello mushrooms that have been exposed to UV light. Fortified nut milks can also help you get vitamin D during the winter months. In some cases, however, a vitamin D supplement may be needed.

A vegan diet is also deficient in two omega-3 fatty acids called eicosapentaenoic acid and docosahexaenoic acid that your body needs for a healthy heart and eyes and brain function. Eating foods such as walnuts, soy, pumpkin, flax, or chia seeds , will help increase your intake of an omega-3 fatty acid called alpha-linolenic acid, which your body converts to the other two forms. Still, supplementing with a product such as a micro algae supplement may be needed. Also, if you're pregnant, however, it is important to talk to your healthcare provider to make sure you get enough omega-3s during your pregnancy.

Lastly, iron is a nutrient of concern in vegan diets. According to the Vegan Society, good plant sources of iron include lentils, chickpeas, beans, tofu, cashew nuts, chia seeds, ground linseed, hemp seeds, pumpkin seeds, kale, dried apricots and figs, raisins, quinoa and fortified breakfast cereal.

Requires Diligence

Those who follow a vegan diet will need to become accustomed to carefully reading nutrition labels and ingredient lists, especially if they choose to consume processed foods . Foods that you might assume to be free from animal by-products may contain gelatin, whey, casein, honey, or other foods that are non-compliant on a vegan diet.

You'll also need to carefully read nutrition labels to stay healthy on a vegan diet. It is important to choose foods that contain important vitamins and minerals to avoid nutritional deficiencies.

Difficulty Dining Out

When shopping for vegan-friendly food, consumers can read product information. But if you eat at someone's home or in a restaurant, you don't have access to an ingredient list. For this reason, dining out can be a challenge for those who choose a vegan diet.

A few restaurants make a note of vegan or vegetarian foods on their menus, but not many. You may be able to create a vegan meal from the salads or side dishes that they already serve. However, you'll need to ask to be sure that no animal products are used in the preparation.

And sometimes, even asking about food isn't helpful. It is not uncommon for well-meaning restaurant staff (or well-intentioned friends and family) to assume that plant-based foods are vegan if they don't contain dairy. But that isn't always the case. Vegetable soup, for example, might be made with broth that used an animal bone for flavoring.

Many vegan experts recommend that when dining at someone's home, bring a recipe that you can enjoy and that you can share with others. And choose restaurants that you know to be vegan-savvy.

Unrealistic Expectations

While consuming a vegan diet is likely to produce health benefits and a healthier weight, it is not a guarantee. For example, if you are trying to slim down, you still need to be mindful of the foods you choose and the amount you eat.

There is an increasing number of heavily processed vegan foods. Many times, these foods are just as unhealthy—containing more fat and calories—as their traditional counterparts.

And health benefits are not a slam dunk either. A study published in the  Journal of the American College of Cardiology compared a large number of women who ate a healthy vegan diet (including whole grains, fruits, vegetables, nuts, legumes, oils, tea and coffee) to those who ate a less healthy vegan food (including juices, sweetened beverages, refined grains, potatoes, fries, and sweets). Researchers concluded that the healthier vegan diet resulted in a substantially lower risk for heart disease, whereas the less healthy vegan diet was associated with a higher risk.   

Social Isolation

People's food choices can come under scrutiny from friends, family, coworkers, and other acquaintances. While veganism is more normalized these days and plant-based foods are more widely available, you might still find that you are questioned and challenged about your reasons for choosing this lifestyle. Additionally, those who don't know how to accommodate your diet may exclude you from social gatherings. Or worse, they may invite you and encourage you to eat foods that are not vegan-friendly.

Some vegan blogs address these issues and provide guidance for those adapting to the eating style. Experts advise that you reach out to other vegans in your community and build a network, while also being patient with those who don't understand your choices.

Clarys P, Deliens T, Huybrechts I, et al. Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet.   Nutrients . 2014;6(3):1318–1332. doi:10.3390/nu6031318

Le, L., & Sabaté, J. (2014). Beyond Meatless, the Health Effects of Vegan Diets: Findings from the Adventist Cohorts . Nutrients, 6(6), 2131–2147. doi:10.3390/nu6062131

Mantzios M. Editorial: Mindfulness and Eating Behavior .  Front Psychol . 2018;9:1986. doi:10.3389/fpsyg.2018.01986

Turner-McGrievy G, Mandes T, Crimarco A. A plant-based diet for overweight and obesity prevention and treatment.   J Geriatr Cardiol . 2017;14(5):369–374. doi:10.11909/j.issn.1671-5411.2017.05.002

Moore W, McGrievy M, Turner-McGrievy G.   Dietary adherence and acceptability of five different diets, including vegan and vegetarian diets, for weight loss : The New DIETs study.  Eating Behaviors . 2015;19:33-38.

Castañé, S., & Antón, A. (2017). Assessment of the nutritional quality and environmental impact of two food diets: A Mediterranean and a vegan diet . Journal of Cleaner Production, 167, 929–937. doi:10.1016/j.jclepro.2017.04.121

Janssen, M., Busch, C., Rödiger, M., & Hamm, U. (2016). Motives of consumers following a vegan diet and their attitudes towards animal agriculture . Appetite, 105, 643–651. doi:10.1016/j.appet.2016.06.039

Radnitz, C., Beezhold, B., & DiMatteo, J. (2015). Investigation of lifestyle choices of individuals following a vegan diet for health and ethical reasons . Appetite, 90, 31–36. doi:10.1016/j.appet.2015.02.026

Rizzo G, Laganà AS, Rapisarda AM, et al. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation .  Nutrients . 2016;8(12):767. doi:10.3390/nu8120767

Sakkas H, Bozidis P, Touzios C, et al. Nutritional status and the influence of the vegan diet on the gut microbiota and human mealth .  Medicina (Kaunas) . 2020;56(2):88. doi:10.3390/medicina56020088

Iron . The Vegan Society.

Satija A, Bhupathiraju S. et al.   Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults .  Journal of the American College of Cardiology . 2017;70(4):411-422. doi:10.1016/j.jacc.2017.05.047

Alexander S, Ostfeld RJ, Allen K, Williams KA. A plant-based diet and hypertension .  J Geriatr Cardiol . 2017;14(5):327–330. doi:10.11909/j.issn.1671-5411.2017.05.014

Clarys P, Deliens T, Huybrechts I, et al. Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet.   Nutrients . 2014;6(3):1318–1332. Published 2014 Mar 24. doi:10.3390/nu6031318

Harvard Women's Health Watch. " Becoming a Vegetarian ."

Kahleova H, Fleeman R, Hlozkova A, Holubkov R, Barnard ND. A plant-based diet in overweight individuals in a 16-week randomized clinical trial: metabolic benefits of plant protein.   Nutr Diabetes . 2018;8(1):58. Published 2018 Nov 2. doi:10.1038/s41387-018-0067-4

Mantzios M. Editorial: Mindfulness and Eating Behavior .  Front Psychol . 2018;9:1986. Published 2018 Oct 12. doi:10.3389/fpsyg.2018.01986

Moore W, McGrievy M, Turner-McGrievy G.  Dietary adherence and acceptability of five different diets, including vegan and vegetarian diets, for weight loss : The New DIETs study.  Eating Behaviors . 2015;19:33-38.

Satija A, Bhupathiraju S. et al.  Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults .  Journal of the American College of Cardiology . 2017;70(4):411-422. doi:10.1016/j.jacc.2017.05.047

• Craig WJ. " Health Effects of Vegan Diets ."  Am J Clin Nutr . 2009 May;89(5):1627S-1633S.

By Shereen Lehman, MS Shereen Lehman, MS, is a former writer for Verywell Fit and Reuters Health. She's a healthcare journalist who writes about healthy eating and offers evidence-based advice for regular people.

Essays About Veganism: Top 5 Examples and 10 Prompts

Veganism is on the rise. See below for our great examples of essays about veganism and helpful writing prompts to get started. 

Veganism is the practice of abstaining from animal-based foods and products. The movement originated from the philosophies against using animals as commodities and for capitalist gains. Now a booming industry, veganism promises better health benefits, a more humane world for animals, and an effective solution to global warming. 

Here is our round-up of essays examples about veganism:

1. A Brief History of Veganism by Claire Suddath

2. animal testing on plant-based ingredients divides vegan community by jill ettinger, 3. as vegan activism grows, politicians aim to protect agri-business, restaurateurs by alexia renard, 4. bezos, gates back fake meat and dairy made from fungus as next big alt-protein by bob woods, 5. going vegan: can switching to a plant-based diet really save the planet by sarah marsh, 1. health pros and cons of veganism, 2. veganism vs. vegetarianism, 3. the vegan society, 4. making a vegan diet plan, 5. profitability of vegan restaurants, 6. public personalities who are vegan, 7. the rise of different vegan products, 8. is vegan better for athletes, 9. vegans in your community, 10. most popular vegan activists.

“Veganism is an extreme form of vegetarianism, and though the term was coined in 1944, the concept of flesh-avoidance can be traced back to ancient Indian and eastern Mediterranean societies.”

Suddath maps out the historical roots of veganism and the global routes of its influences. She also laid down its evolution in various countries where vegan food choices became more flexible in considering animal-derived products critical to health. 

“Along with eschewing animal products at mealtime, vegans don’t support other practices that harm animals, including animal testing. But it’s a process rampant in both the food and drug industries.”

Ettinger follows the case of two vegan-founded startups that ironically conducts animal testing to evaluate the safety of their vegan ingredients for human consumption. The essay brings to light the conflicts between the need to launch more vegan products and ensuring the safety of consumers through FDA-required animal tests. 

“Indeed, at a time when the supply of vegan products is increasing, activists sometimes fear the reduction of veganism to a depoliticized way of life that has been taken over by the food industry.”

The author reflects on a series of recent vegan and animal rights activist movements and implies disappointment over the government’s response to protect public safety rather than support the protests’ cause. The essay differentiates the many ways one promotes and fights for veganism and animal rights but emphasizes the effectiveness of collective action in shaping better societies. 

“Beyond fungus, Nature’s Fynd also is representative of the food sustainability movement, whose mission is to reduce the carbon footprint of global food systems, which generate 34% of greenhouse emissions linked to climate change.”

The essay features a company that produces alternative meat products and has the backing of Jeff Bezos, Bill Gates, and Al Gore. The essay divulges the company’s investments and plans to expand in the vegan market while providing a picture of the burgeoning alternative foods sector. 

“Experts say changing the way we eat is necessary for the future of the planet but that government policy is needed alongside this. If politicians are serious about wanting dietary changes, they also need to incentivise it, scientists and writers add.”

The article conveys the insights and recommendations of environmental and agriculture experts on how to turn more individuals into vegans. The experts emphasize the need for a whole-of-society approach in shifting more diets to vegan instead of putting the onus for change on an individual. 

10 Writing Prompts on Essays About Veganism

Here is our round-up of the best prompts to create interesting essays about veganism: 

While veganism has been a top choice for those desiring to lose weight and have a healthier lifestyle, some studies have also shown its detrimental effects on health due to deficiencies in specific vitamins. First, find out what existing research and experts say about this. Then, lay down the advantages and disadvantages of going vegan, explain each, and wrap up your essay with your insights.

Differentiate veganism from vegetarianism. Tackle the foods vegans and vegetarians consume and do not consume and cite the different effects they have on your health and the environment. You may also expand this prompt to discuss the other dietary choices that spawned from veganism. 

The Vegan Society is a UK-based non-profit organization aimed at educating the public on the ways of veganism and promoting this as a way of life to as many people. Expound on its history, key organizational pillars, and recent and future campaigns. You may also broaden this prompt by listing down vegan organizations around the world. Then discuss each one’s objectives and campaigns. 

Write down the healthiest foods you recommend your readers to include in a vegan diet plan. Contrary to myths, vegan foods can be very flavorful depending on how they are cooked and prepared. You may expand this prompt to add recommendations for the most flavorful spices and sauces to take any vegan recipe a notch higher. 

Vegan restaurants were originally a niche market. But with the rise of vegan food products and several multinational firms’ foray into the market, the momentum for vegan restaurants was launched into an upward trajectory—research on how profitable vegan restaurants are against restos offering meat on the menu. You may also recommend innovative business strategies for a starting vegan restaurant to thrive and stay competitive in the market. 

From J.Lo to Bill Gates, there is an increasing number of famous personalities who are riding the vegan trend with good reason. So first, list a few celebrities, influencers, and public figures who are known advocates of veganism. Then, research and write about stories that compelled them to change their dietary preference.

The market for vegan-based non-food products is rising, from makeup to leather bags and clothes. First, create a list of vegan brands that are growing in popularity. Then, research the materials they use and the processes they employ to preserve the vegan principles. This may prompt may also turn into a list of the best gift ideas for vegans.

Many believe that a high-protein diet is a must for athletes. However, several athletes have dispelled the myth that vegan diets lack the protein levels for rigorous training and demanding competition. First, delve deeper into the vegan foods that serve as meat alternatives regarding protein intake. Then, cite other health benefits a vegan diet can offer to athletes. You may also add research on what vegan athletes say about how a vegan diet gives them energy. 

Interview people in your community who are vegan. Write about how they made the decision and how they transitioned to this lifestyle. What were the initial challenges in their journey, and how did they overcome these? Also, ask them for tips they would recommend to those who are struggling to uphold their veganism.

Make a list of the most popular vegan activists. You may narrow your list to personalities in digital media who are speaking loud and proud about their lifestyle choice and trying to inspire others to convert. Narrate the ways they have made and are making an impact in their communities. 

To enhance your essay, read our guide explaining what is persuasive writing . 

If you’d like to learn more, check out our guide on how to write an argumentative essay .

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• Published: 12 September 2019

The effects of plant-based diets on the body and the brain: a systematic review

• Evelyn Medawar   ORCID: orcid.org/0000-0001-5011-8275 1 , 2 , 3 ,
• Sebastian Huhn 4 ,
• Arno Villringer 1 , 2 , 3 &
• A. Veronica Witte 1  

Translational Psychiatry volume  9 , Article number:  226 ( 2019 ) Cite this article

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• Human behaviour
• Molecular neuroscience
• Psychiatric disorders

Western societies notice an increasing interest in plant-based eating patterns such as vegetarian and vegan, yet potential effects on the body and brain are a matter of debate. Therefore, we systematically reviewed existing human interventional studies on putative effects of a plant-based diet on the metabolism and cognition, and what is known about the underlying mechanisms. Using the search terms “plant-based OR vegan OR vegetarian AND diet AND intervention” in PubMed filtered for clinical trials in humans retrieved 205 studies out of which 27, plus an additional search extending the selection to another five studies, were eligible for inclusion based on three independent ratings. We found robust evidence for short- to moderate-term beneficial effects of plant-based diets versus conventional diets (duration ≤ 24 months) on weight status, energy metabolism and systemic inflammation in healthy participants, obese and type-2 diabetes patients. Initial experimental studies proposed novel microbiome-related pathways, by which plant-based diets modulate the gut microbiome towards a favorable diversity of bacteria species, yet a functional “bottom up” signaling of plant-based diet-induced microbial changes remains highly speculative. In addition, little is known, based on interventional studies about cognitive effects linked to plant-based diets. Thus, a causal impact of plant-based diets on cognitive functions, mental and neurological health and respective underlying mechanisms has yet to be demonstrated. In sum, the increasing interest for plant-based diets raises the opportunity for developing novel preventive and therapeutic strategies against obesity, eating disorders and related comorbidities. Still, putative effects of plant-based diets on brain health and cognitive functions as well as the underlying mechanisms remain largely unexplored and new studies need to address these questions.

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Introduction.

Western societies notice an increasing interest in plant-based eating patterns such as avoiding meat or fish or fully excluding animal products (vegetarian or vegan, see Fig.  1 ). In 2015, around 0.4−3.4% US adults, 1−2% British adults, and 5−10% of German adults were reported to eat largely plant-based diets 1 , 2 , 3 , 4 , due to various reasons (reviewed in ref. 5 ). Likewise, the number of scientific publications on PubMed (Fig.  2 ) and the public popularity as depicted by Google Trends (Fig.  3 ) underscore the increased interest in plant-based diets. This increasing awareness calls for a better scientific understanding of how plant-based diets affect human health, in particular with regard to potentially relevant effects on mental health and cognitive functions.

From left to right: including all food items (omnivore), including all except for meat (pesco-vegetarian) or meat and fish (ovo-lacto-vegetarian) to including only plant-based items (vegan)

Frequency of publications on PubMed including the search terms “vegan” (in light green), vegetarian (in orange) and plant-based (dark green)—accessed on 19 April 2019

Note indicates technical improvements implemented by Google Trends. Data source: Google Trends . Search performed on 18 April 2019

A potential effect of plant-based diets on mortality rate remains controversial: large epidemiological studies like the Adventist studies ( n  = 22,000−96,000) show a link between plant-based diets, lower all-cause mortality and cardiovascular diseases 6 , 7 , while other studies like the EPIC-Oxford study and the “45 and Up Study” ( n  = 64,000−267,000) show none 8 , 9 . Yet, many, but not all, epidemiological and interventional human studies in the last decades have suggested that plant-based diets exert beneficial health effects with regard to obesity-related metabolic dysfunction, type 2 diabetes mellitus (T2DM) and chronic low-grade inflammation (e.g. refs. 6 , 7 , 10 , 11 , for reviews, see refs. 12 , 13 , 14 , 15 , 16 , 17 , 18 ). However, while a putative link between such metabolic alterations and brain health through pathways which might include diet-related neurotransmitter precursors, inflammatory pathways and the gut microbiome 19 becomes increasingly recognized, the notion that plant-based diets exert influence on mental health and cognitive functions appears less documented and controversial 20 , 21 , 22 , 23 , 24 . We therefore systematically reviewed the current evidence based on available controlled interventional trials, regarded as the gold standard to assess causality, on potential effects of plant-based diets on (a) metabolic factors including the microbiome and (b) neurological or psychiatric health and brain functions. In addition, we aimed to evaluate potential underlying mechanisms and related implications for cognition.

We performed a systematic PubMed search with the following search terms “plant-based OR vegan OR vegetarian AND diet AND intervention” with the filter “clinical trial” and “humans”, preregistered at PROSPERO (CRD42018111856; https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=111856 ) (Suppl. Fig.  1 ). PubMed was used as search engine because it was esteemed to yield the majority of relevant human clinical trials from a medical perspective. Exclusion criteria were insufficient design quality (such as lack of a control group), interventions without a plant-based or vegetarian or vegan diet condition, intervention with multiple factors (such as exercise and diet), and the exclusive report of main outcomes of no interest, such as dietary compliance, nutrient intake (such as vitamins or fiber intake), or nonmetabolic (i.e., not concerning glucose metabolism, lipid profile, gastrointestinal hormones or inflammatory markers) or non-neurological/psychiatric disease outcomes (e.g. cancer, caries).

Studies were independently rated for eligibility into the systematic review by three authors based on reading the abstract and, if needed, methods or other parts of the publication. If opinions differed, a consensus was reached through discussion of the individual study. This yielded 27 eligible out of 205 publications; see Table  1 for details. To increase the search radius for studies dealing with microbial and neurological/psychiatric outcomes, we deleted the search term “intervention”, which increased the number of studies by around one third, and checked for studies with “microbiome/microbiota”, “mental”, “cognitive/cognition” or “psychological/psychology” in the resulting records. Through this, we retrieved another five studies included in Table  1 . Further related studies were reviewed based on additional nonsystematic literature search.

Section I: Effects of plant-based diets on body and brain outcomes

Results based on interventional studies on metabolism, microbiota and brain function.

Overall, the vast majority of studies included in this systematic review reported a short-term beneficial effect of plant-based dietary interventions (study duration 3−24 months) on weight status, glucose, insulin and/or plasma lipids and inflammatory markers, whereas studies investigating whether plant-based diets affect microbial or neurological/psychiatric disease status and other brain functions were scarce and rather inconclusive (Table  1 ).

More specifically, 19 out of 32 studies dealing with T2DM and/or obese subjects and seven out of 32 dealing with healthy subjects observed a more pronounced weight loss and metabolic improvements, such as lowering of glycated hemoglobin (HbA1c)—a long-term marker for glucose levels—decreased serum levels of low-density (LDL) and high-density lipoproteins (HDL) and total cholesterol (TC), after a plant-based diet compared to an omnivore diet. This is largely in line with recent meta-analyses indicating beneficial metabolic changes after a plant-based diet 25 , 26 , 27 .

For example, Lee et al. found a significantly larger reduction of HbA1c and lower waist circumference after vegan compared to conventional dieting 28 . Jenkins et al. found a disease-attenuating effect in hyperlipidemic patients after 6 months adopting a low-carbohydrate plant-based diet compared to a high-carbohydrate lacto-ovo-vegetarian diet 29 , 30 . However, lower energy intake in the vegan dieters might have contributed to these effects. Yet, while a plant-based diet per se might lead to lower caloric intake, other studies observed nonsignificant trends toward higher effect sizes on metabolic parameters after a vegan diet, even when caloric intake was comparable: two studies in T2DM patients 31 , 32 compared calorie-unrestricted vegan or vegetarian to calorie-restricted conventional diets over periods of 6 months and 1.5 years, respectively, in moderate sample sizes ( n  ~ 75−99) with similar caloric intake achieved in both diet groups. Both studies indicated stronger effects of plant-based diets on disease status, such as reduced medication, improved weight status and increased glucose/insulin sensitivity, proposing a diabetes-preventive potential of plant-based diets. Further, a five-arm study comparing four types of plant-based diets (vegan, vegetarian, pesco-vegetarian, semi-vegetarian) to an omnivore diet (total n  = 63) in obese participants found the most pronounced effect on weight loss for a vegan diet (−7.5 ± 4.5% of total body weight) 33 . Here, inflammation markers conceptualized as the dietary inflammatory index were also found to be lower in vegan, vegetarian and pesco-vegetarian compared to semi-vegetarian overweight to obese dieters 33 .

Intriguingly, these results 28 , 29 , 30 , 31 , 32 , 33 cohesively suggest that although caloric intake was similar across groups, participants who had followed a vegan diet showed higher weight loss and improved metabolic status.

As a limitation, all of the reviewed intervention studies were carried out in moderate sample sizes and over a period of less than 2 years, disregarding that long-term success of dietary interventions stabilizes after 2−5 years only 34 . Future studies with larger sample sizes and tight control of dietary intake need to confirm these results.

Through our systematic review we retrieved only one study that added the gut microbiome as novel outcome for clinical trials investigating the effects of animal-based diets compared to plant-based diets. While the sample size was relatively low ( n  = 10, cross-over within subject design), it showed that changing animal- to plant based diet changed gut microbial activity towards a trade-off between carbohydrate and protein fermentation processes within only 5 days 35 . This is in line with another controlled-feeding study where microbial composition changes already occurred 24 h after changing diet (not exclusively plant-based) 36 . However, future studies incorporating larger sample sizes and a uniform analysis approach of microbial features need to further confirm the hypothesis that a plant-based diet ameliorates microbial diversity and health-related bacteria species.

Considering neurological or psychiatric diseases and brain functions, the systematic review yielded in six clinical trials of diverse clinical groups, i.e. migraine, multiple sclerosis, fibromyalgia and rheumatoid arthritis. Here, mild to moderate improvement, e.g. measured by antibody levels, symptom improvement or pain frequency, was reported in five out of six studies, sometimes accompanied by weight loss 37 , 38 , 39 , 40 (Table  1 ). However, given the pilot character of these studies, indicated by small sample sizes ( n  = 32−66), lack of randomization 37 , or that the plant-based diet was additionally free of gluten 40 , the evidence is largely anecdotal. One study in moderately obese women showed no effects on psychological outcomes 41 , two studies with obese and nonobese healthy adults indicated improvements in anxiety, stress and depressive symptom scores 23 , 24 . Taken together, the current evidence based on interventional trials regarding improvements of cognitive and emotional markers and in disease treatment for central nervous system disorders such as multiple sclerosis or fibromyalgia remains considerably fragmentary for plant-based diets.

Among observational studies, a recent large cross-sectional study showed a higher occurrence of depressive symptoms for vegetarian dieters compared to nonvegetarians 20 . Conversely, another observational study with a sample of about 80% women found a beneficial association between a vegan diet and mood disturbance 24 .

Overall, the relationship between mental health (i.e. depression) and restrictive eating patterns has been the focus of recent research 20 , 21 , 22 , 24 , 42 ; however, causal relationships remain uninvestigated due to the observational design.

Underlying mechanisms linking macronutrient intake to metabolic processes

On the one hand, nutrient sources as well as their intake ratios considerably differ between plant-based and omnivore diets (Suppl. Table  1 ), and on the other hand, dietary micro- and macromolecules as well as their metabolic substrates affect a diversity of physiological functions, pointing to complex interdependencies. Thus, it seems difficult to nail down the proposed beneficial effects of a plant-based diet on metabolic status to one specific component or characteristic, and it seems unlikely that the usually low amount of calories in plant-based diets could explain all observed effects. Rather, plant-based diets might act through multiple pathways, including better glycemic control 43 , lower inflammatory activity 44 and altered neurotransmitter metabolism via dietary intake 45 or intestinal activity 46 (Fig.  4 ).

BMI body-mass-index, HbA1c hemoglobin A1c, LDL-cholesterol low-density lipoprotein cholesterol, Trp tryptophan, Tyr tyrosine. Images from commons.wikimedia.org , “Brain human sagittal section” by Lynch 2006 and “Complete GI tract” by Häggström 2008, “Anatomy Figure Vector Clipart” by http://moziru.com

On the macronutrient level, plant-based diets feature different types of fatty acids (mono- and poly-unsaturated versus saturated and trans) and sugars (complex and unrefined versus simple and refined), which might both be important players for mediating beneficial health effects 18 . On the micronutrient level, the EPIC-Oxford study provided the largest sample of vegan dieters worldwide ( n (vegan) = 2396, n (total) = 65,429) and showed on the one hand lower intake of saturated fatty acids (SFA), retinol, vitamin B12 and D, calcium, zinc and protein, and on the other hand higher intake of fiber, magnesium, iron, folic acid, vitamin B1, C and E in vegan compared to omnivore dieters 47 . Other studies confirmed the variance of nutrient intake across dietary groups, i.e. omnivores, vegetarians and vegans, showing the occurrence of critical nutrients for each group 48 , 49 . Not only the amount of SFA but also its source and profile might be important factors regulating metabolic control (reviewed in ref. 14 ), for example through contributing to systemic hyperlipidemia and subsequent cardiovascular risk. Recently, it has been shown in a 4-week intervention trial that short-term dietary changes favoring a diet high in animal-based protein may lead to an increased risk for cardiovascular derangements mediated by higher levels of trimethylamine N-oxide (TMAO), which is a metabolite of gut bacteria-driven metabolic pathways 50 .

Secondly, high fiber intake from legumes, grains, vegetables and fruits is a prominent feature of plant-based diets (Table  1 ), which could induce beneficial metabolic processes like upregulated carbohydrate fermentation and downregulated protein fermentation 35 , improved gut hormonal-driven appetite regulation 51 , 52 , 53 , 54 , 55 , and might prevent chronic diseases such as obesity and T2DM by slowing down digestion and improving lipid control 56 . A comprehensive review including evidence from 185 prospective studies and 58 clinical trials concluded that risk reduction for a myriad of diseases (incl. CVD, T2DM, stroke incidence) was greatest for daily fiber intake between 25 and 29 g 57 . Precise evidence for underlying mechanisms is missing; however, more recently it has been suggested that high fiber intake induces changes on the microbial level leading to lower long-term weight gain 58 , a mechanism discussed below.

The reason for lower systemic inflammation in plant-based dieters could be due to the abundance of antiinflammatory molecule intake and/or avoidance of proinflammatory animal-derived molecules. Assessing systemic inflammation is particularly relevant for medical conditions such as obesity, where it has been proposed to increase the risk for cardiovascular disease 59 , 60 . In addition, higher C-reactive protein (CRP) and interleukin-6 (IL-6) levels have been linked with measures of brain microstructure, such as microstructural integrity and white matter lesions 61 , 62 , 63 and higher risk of dementia 64 , and recent studies point out that a diet-related low inflammatory index might also directly affect healthy brain ageing 65 , 66 .

Interventional studies that focus on plant- versus meat-based proteins or micronutrients and potential effects on the body and brain are lacking. A meta-analysis including seven RCTs and one cross-sectional studies on physical performance and dietary habits concluded that a vegetarian diet did not adversely influence physical performance compared to an omnivore diet 67 . An epidemiological study by Song et al. 11 estimated that statistically replacing 3% of animal protein, especially from red meat or eggs, with plant protein would significantly improve mortality rates. This beneficial effect might however not be explained by the protein source itself, but possibly by detrimental components found in meat (e.g. heme-iron or nitrosamines, antibiotics, see below).

Some studies further hypothesized that health benefits observed in a plant-based diet stem from higher levels of fruits and vegetables providing phytochemicals or vitamin C that might boost immune function and eventually prevent certain types of cancer 68 , 69 , 70 . A meta-analysis on the effect of phytochemical intake concluded a beneficial effect on CVD, cancer, overweight, body composition, glucose tolerance, digestion and mental health 71 . Looking further on the impact of micronutrients and single dietary compounds, there is room for speculation that molecules, that are commonly avoided in plant-based diets, might affect metabolic status and overall health, such as opioid-peptides derived from casein 72 , pre- and probiotics 73 , 74 , carry-over antibiotics found in animal products 75 , 76 or food-related carcinogenic toxins, such as dioxin found in eggs or nitrosamines found in red and processed meat 77 , 78 . Although conclusive evidence is missing, these findings propose indirect beneficial effects on health deriving from plant-based compared to animal-based foods, with a potential role for nonprotein substances in mediating those effects 18 . While data regarding chemical contaminant levels (such as crop pesticides, herbicides or heavy metals) in different food items are fragmentary only, certain potentially harmful compounds may be more (or less) frequently consumed in plant-based diets compared to more animal-based diets 79 . Whether these differences lead to systematic health effects need to be explored.

Taken together, the reviewed studies indicating effects of plant-based diets through macro- and micronutrient intake reveal both the potential of single ingredients or food groups (low SFA, high fiber) and the immense complexity of diet-related mechanisms for metabolic health. As proposed by several authors, benefits on health related to diet can probably not be viewed in isolation for the intake (or nonintake) of specific foods, but rather by additive or even synergistic effects between them (reviewed in refs. 12 , 80 ). Even if it remains a challenging task to design long-term RCTs that control macro- and micronutrient levels across dietary intervention groups, technological advancements such as more fine-tuned diagnostic measurements and automated self-monitoring tools, e.g. automatic food recognition systems 81 and urine-related measures of dietary intake 82 , could help to push the field forward.

Nutrients of particular interest in plant-based diets

As described above, plant-based diets have been shown to convey nutritional benefits 48 , 49 , in particular increased fiber, beta carotene, vitamin K and C, folate, magnesium, and potassium intake and an improved dietary health index 83 . However, a major criticism of plant-based diets is the risk of nutrient deficiencies for specific micronutrients, especially vitamin B12, a mainly animal-derived nutrient, which is missing entirely in vegan diets unless supplemented or provided in B12-fortified products, and which seems detrimental for neurological and cognitive health when intake is low. In the EPIC-Oxford study about 50% of the vegan dieters showed serum levels indicating vitamin B12 deficiency 84 . Along other risk factors such as age 85 , diet, and plant-based diets in particular, seem to be the main risk factor for vitamin B12 deficiency (reviewed in ref. 86 ), and therefore supplementing vitamin B12 for these risk groups is highly recommended 87 . Vitamin B12 is a crucial component involved in early brain development, in maintaining normal central nervous system function 88 and suggested to be neuroprotective, particularly for memory performance and hippocampal microstructure 89 . One hypothesis is that high levels of homocysteine, that is associated with vitamin B12 deficiency, might be harmful to the body. Vitamin B12 is the essential cofactor required for the conversion of homocysteine into nonharmful components and serves as a cofactor in different enzymatic reactions. A person suffering from vitamin B12 insufficiency accumulates homocysteine, lastly promoting the formation of plaques in arteries and thereby increasing atherothrombotic risk 90 , possibly facilitating symptoms in patients of Alzheimer’s disease 91 . A meta-analysis found that vitamin B12 deficiency was associated with stroke, Alzheimer’s disease, vascular dementia, Parkinson’s disease and in even lower concentrations with cognitive impairment 92 , supporting the claim of its high potential for disease prevention when avoided or treated 93 . Further investigations and longitudinal studies are needed, possibly measuring holotranscobalamin (the active form of vitamin B12) as a more specific and sensitive marker for vitamin B12 status 94 , to examine in how far nonsupplementing vegan dieters could be at risk for cardiovascular and cognitive impairment.

Similar health dangers can stem from iron deficiency, another commonly assumed risk for plant-based dieters and other risk groups such as young women. A meta-analysis on 24 studies proposes that although serum ferritin levels were lower in vegetarians on average, it is recommended to sustain an optimal ferritin level (neither too low nor too high), calling for well-monitored supplementation strategies 95 . Iron deficiency is not only dependent on iron intake as such but also on complimentary dietary factors influencing its bioavailability (discussed in ref. 95 ). The picture remains complex: on the one hand iron deficiency may lead to detrimental health effects, such as impairments in early brain development and cognitive functions in adults and in children carried by iron-deficient mothers 96 and a possible role for iron overload in the brain on cognitive impairment on the other hand 97 . One study showed that attention, memory and learning were impaired in iron-deficient compared to iron-sufficient women, which could be restored after a 4-month oral iron supplementation ( n  = 118) 98 . Iron deficiency-related impairments could be attributed to anemia as an underlying cause, possibly leading to fatigue, or an undersupply of blood to the brain or alterations in neurobiological and neuronal systems 99 provoking impaired cognitive functioning.

This leads to the general recommendation to monitor health status by frequent blood tests, to consult a dietician to live healthily on a plant-based diet and to consider supplements to avoid nutrient deficiencies or nutrient-overdose-related toxicity. All in all, organizations such as the Academy of Nutrition and Dietetics 100 and the German Nutrition Society do not judge iron as a major risk factor for plant-based dieters 101 .

Section II: Effects of diet on the gut microbiome

The link between diet and microbial diversity.

Another putative mechanistic pathway of how plant-based diets can affect health may involve the gut microbiome which has increasingly received scientific and popular interest, lastly not only through initiatives such as the Human Microbiome Project 102 . A common measure for characterizing the gut community is enterotyping, which is a way to stratify individuals according to their gut bacterial diversity, by calculating the ratio between bacterial genera, such as Prevotella and Bacteroides 103 . While interventional controlled trials are still scarce, this ratio has been shown to be conclusive for differentiating plant-based from animal-based microbial profiles 36 . Specifically, in a sample of 98 individuals, Wu et al. 36 found that a diet high in protein and animal fats was related to more Bacteroides, whereas a diet high in carbohydrates, representing a plant-based one, was associated with more Prevotella. Moreover, the authors showed that a change in diet to high-fat/low-fiber or to low-fat/high-fiber in ten individuals elicited a change in gut microbial enterotype with a time delay of 24 h only and remained stable over 10 days, however not being able to switch completely to another enterotype 36 . Another strictly controlled 30-day cross-over interventional study showed that a change in diet to either an exclusively animal-based or plant-based diet promoted gut microbiota diversity and genetic expression to change within 5 days 35 . Particularly, in response to adopting an animal-based diet, microbial diversity increased rapidly, even overshadowing individual microbial gene expression. Beyond large shifts in overall diet, already modest dietary modifications such as the daily consumption of 43 g of walnuts, were able to promote probiotic- and butyric acid-producing bacterial species in two RCTs, after 3 and 8 weeks respectively 104 , 105 , highlighting the high adaptability of the gut microbiome to dietary components. The Prevotella to Bacteroides ratio (P/B) has been shown to be involved in the success of dietary interventions targeting weight loss, with larger weight loss in high P/B compared to low P/B in a 6-month whole-grain diet compared to a conventional diet 106 . Only recently, other microbial communities, such as the salivary microbiome, have been shown to be different between omnivores and vegan dieters 107 , opening new avenues for research on adaptable mechanisms related to dietary intake.

A continuum in microbial diversity dependent on diet

Plant-based diets are supposed to be linked to a specific microbial profile, with a vegan profile being most different from an omnivore, but not always different from a vegetarian profile (reviewed in ref. 15 ). Some specifically vegan gut microbial characteristics have also been found in a small sample of six obese subjects after 1 month following a vegetarian diet, namely less pathobionts, more protective bacterial species improving lipid metabolism and a reduced level of intestinal inflammation 108 . Investigating long-term dietary patterns a study found a dose-dependent effect for altered gut microbiota in vegetarians and vegans compared to omnivores depending on the quantity of animal products 109 . The authors showed that gut microbial profiles of plant-based diets feature the same total number but lower counts of Bacteroides, Bifidobacterium, E. coli and Enterobacteriaceae compared to omnivores, with the biggest difference to vegans. Still today it remains unclear, what this shift in bacterial composition means in functional terms, prompting the field to develop more functional analyses.

In a 30-day intervention study, David et al. found that fermentation processes linked to fat and carbohydrate decomposition were related to the abundance of certain microbial species 35 . They found a strong correlation between fiber intake and Prevotella abundance in the microbial gut. More recently, Prevotella has been associated with plant-based diets 110 that are comparable to low-fat/high-fiber diets 111 and might be linked to the increased synthesis of short-chain fatty acids (SCFA) 112 . SCFAs are discussed as putative signaling molecules between the gut microbiome and the receptors, i.e. free fatty acid receptor 2 (FFA2) 51 , found in host cells across different tissues 113 and could therefore be one potential mechanism of microbiome−host communication.

The underlying mechanisms of nutrient decomposition by Prevotella and whether abundant Prevotella populations in the gut are beneficial for overall health remain unknown. Yet it seems possible that an increased fiber intake and therefore higher Prevotella abundance such as associated with plant-based diets is beneficial for regulating glycemic control and keeping inflammatory processes within normal levels, possibly due to reduced appetite and lower energy intake mediated by a higher fiber content 114 . Moreover, it has been brought forward that the microbiome might influence bodily homeostatic control, suggesting a role for the gut microbiota in whole-body control mechanisms on the systemic level. Novel strategies aim to develop gut-microbiota-based therapies to improve bodily states, e.g. glycemic control 115 , based on inducing microbial changes and thereby eliciting higher-level changes in homeostasis. While highly speculative, such strategies could in theory also exert changes on the brain level, which will be discussed next in the light of a bi-directional feedback between the gut and the brain.

Effects on cognition and behavior linking diet and cognition via the microbiome−gut−brain axis

While the number of interventional studies focusing on cognitive and mental health outcomes after adopting plant-based diets overall is very limited (see Section I above), one underlying mechanism of how plant-based diets may affect mood could involve signaling pathways on the microbiome−gut−brain axis 116 , 117 , 118 , 119 . A recent 4-week intervention RCT showed that probiotic administration compared to placebo and no intervention modulated brain activity during emotional decision-making and emotional recognition tasks 117 . In chronic depression it has been proposed that immunoglobulin A and M antibodies are synthesized by the host in response to gut commensals and are linked to depressive symptoms 120 . Whether the identified gram-negative bacteria might also play a role in plant-based diets remains to be explored. A meta-analysis on five studies concluded that probiotics may mediate an alleviating effect on depression symptomatic 121 —however, sample sizes remained rather small ( n  < 100) and no long-term effects were tested (up to 8 weeks).

Currently, several studies aim to identify microbial profiles in relation to disease and how microbial data can be used on a multimodal way to improve functional resolution, e.g. characterizing microbial profiles of individuals suffering from type-1 diabetes 122 . Yet, evidence for specific effects of diet on cognitive functions and behavior through changes in the microbiome remains scarce. A recent study indicated the possibility that our food choices determine the quantity and quality of neurotransmitter-precursor levels that we ingest, which in turn might influence behavior, as shown by lower fairness during a money-redistribution task, called the ultimatum game, after a high-carbohydrate/protein ratio breakfast than after a low-ratio breakfast 123 . Strang et al. found that precursor forms of serotonin and dopamine, measured in blood serum, predicted behavior in this task, and precursor concentrations were dependent on the nutrient profile of the consumed meal before the task. Also on a cross-sectional level tryptophan metabolites from fecal samples have been associated with amygdala-reward network functional connectivity 124 . On top of the dietary composition per se, the microbiota largely contributes to neurotransmitter precursor concentrations; thus, in addition to measuring neurotransmitter precursors in the serum, metabolomics on fecal samples would be helpful to further understand the functional role of the gut microbiota in neurotransmitter biosynthesis and regulation 125 .

Indicating the relevance of gut microbiota for cognition, a first human study assessing cognitive tests and brain imaging could distinguish obese from nonobese individuals using a microbial profile 126 . The authors found a specific microbiotic profile, particularly defined by Actinobacteria phylum abundance, that was associated with microstructural properties in the hypothalamus and in the caudate nucleus. Further, a preclinical study tested whether probiotics could enhance cognitive function in healthy subjects, showing small effects on improved memory performance and reduced stress levels 127 .

A recent study could show that microbial composition influences cerebral amyloidogenesis in a mouse model for Alzheimer’s disease 128 . Health status of the donor mouse seemingly mattered: fecal transplants from transgenic mice had a larger impact on amyloid beta proliferation in the brain compared to wild-type feces. Translational interpretations to humans should be done with caution if at all—yet the results remain elucidative for showing a link between the gut microbiome and brain metabolism.

The evidence for effects of strictly plant-based diets on cognition is very limited. For other plant-based diets such as the Mediterranean diet or DASH diet, there are more available studies that indicate protective effects on cardiovascular and brain health in the aging population (reviewed in refs. 129 , 130 ). Several attempts have been made to clarify potential underlying mechanisms, for example using supplementary plant polyphenols, fish/fish-oil consumption or whole dietary pattern change in RCTs 131 , 132 , 133 , 134 , 135 , 136 , 137 , yet results are not always equivocal and large-scale intervention studies have yet to be completed.

The overall findings of this paragraph add to the evidence that microbial diversity may be associated with brain health, although underlying mechanisms and candidate signaling molecules remain unknown.

Based on this systematic review of randomized clinical trials, there is an overall robust support for beneficial effects of a plant-based diet on metabolic measures in health and disease. However, the evidence for cognitive and mental effects of a plant-based diet is still inconclusive. Also, it is not clear whether putative effects are due to the diet per se, certain nutrients of the diet (or the avoidance of certain animal-based nutrients) or other factors associated with vegetarian/vegan diets. Evolving concepts argue that emotional distress and mental illnesses are linked to the role of microbiota in neurological function and can be potentially treated via microbial intervention strategies 19 . Moreover, it has been claimed that certain diseases, such as obesity, are caused by a specific microbial composition 138 , and that a balanced gut microbiome is related to healthy ageing 111 . In this light, it seems possible that a plant-based diet is able to influence brain function by still unclear underlying mechanisms of an altered microbial status and systemic metabolic alterations. However, to our knowledge there are no studies linking plant-based diets and cognitive abilities on a neural level, which are urgently needed, due to the hidden potential as a dietary therapeutic tool. Also, further studies are needed to disentangle motivational beliefs on a psychological level that lead to a change in diet from causal effects on the body and the brain mediated e.g., by metabolic alterations or a change in the gut microbiome.

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This work was supported by a scholarship (E.M.) by the German Federal Environmental Foundation and by the grants of the German Research Foundation contract grant number CRC 1052 “Obesity mechanisms” Project A1 (AV) and WI 3342/3-1 (A.V.W.).

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Home — Essay Samples — Life — Vegan — The Positive Effects of Being in a Vegan Diet

The Positive Effects of Being in a Vegan Diet

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The Vegan Diet: A Complete Guide for Beginners

The vegan diet has become very popular. More and more people have decided to go vegan for ethical, environmental, or health reasons.

This type of diet may result in various health benefits , including improved blood sugar control and heart health. It can also help you lose weight, if that’s your goal.

But a diet based exclusively on plant foods may, in some cases, increase your risk of nutrient deficiencies.

That’s where this detailed beginner’s guide to the vegan diet comes in. It aims to cover everything you need to know, so you can follow a vegan diet in a healthful way.

What is the vegan diet?

Veganism is defined as a way of living that attempts to exclude all forms of animal exploitation and cruelty, whether for food, clothing, or any other purpose.

That’s why a vegan diet avoids all animal products, including meat, eggs, and dairy.

People choose to follow a vegan diet for various reasons. These usually range from ethics to environmental concerns, but they can also stem from a desire to improve health.

Summary A vegan diet excludes all animal products. Many people choose to eat this way for ethical, environmental, or health reasons.

Different types of vegan diets

There are different varieties of the vegan diet. The most common include:

• Whole food vegan diet. This diet is based on a wide variety of whole plant foods such as fruits, vegetables, whole grains, legumes, nuts, and seeds.
• Raw food vegan diet. This diet is based on raw fruits, vegetables, nuts, seeds, or plant foods cooked at temperatures below 118°F (48°C) ( 1 ).
• 80/10/10 diet. The 80/10/10 diet is a raw food vegan diet that limits fat-rich plants such as nuts and avocados and relies mainly on raw fruits and soft greens instead. It is also referred to as the low fat, raw food vegan diet or fruitarian diet.
• Starch solution. This is a low fat, high carb vegan diet similar to the 80/10/10 diet, but it focuses on cooked starches like potatoes, rice, and corn instead of fruit.
• Raw till 4. This low fat vegan diet is inspired by the 80/10/10 diet and starch solution. Raw foods are consumed until 4 p.m., with the option of a cooked plant-based meal for dinner.
• Thrive diet. The thrive diet is a raw food vegan diet. Followers eat plant-based, whole foods that are raw or minimally cooked at low temperatures.
• Junk food vegan diet. This is a vegan diet lacking in whole plant foods that relies heavily on mock meats and cheeses, fries, vegan desserts, and other heavily processed vegan foods.

Although several variations of the vegan diet exist, most scientific research rarely differentiates between different types of vegan diets. As a result, the information in this article relates to vegan diets as a whole.

Summary There are several ways to follow a vegan diet, but scientific research rarely differentiates between the different types.

Vegan diets can help you lose weight

Vegans tend to be thinner and have a lower body mass index (BMI) than non-vegans ( 2 , 3 ).

This might explain why an increasing number of people turn to vegan diets as a way to lose weight.

Part of the weight-related benefits vegans experience may be explained by factors other than diet. These may include healthier lifestyle choices, such as physical activity, and other health-related behaviors.

However, several randomized controlled studies, which control for these external factors, report that vegan diets are more effective for weight loss than the diets they are compared to ( 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ).

Interestingly, the weight loss advantage persists even when whole food diets are used as control diets.

These include diets recommended by the American Dietetics Association (ADA), the American Heart Association (AHA), and the National Cholesterol Education Program (NCEP) ( 4 , 5 , 6 , 7 ).

Researchers also generally report that participants on vegan diets lose more weight than those following calorie-restricted diets, even when they’re allowed to eat until they feel full ( 4 , 8 ).

The natural tendency to eat fewer calories on a vegan diet may be caused by a higher dietary fiber intake, which can make you feel fuller.

Summary Vegan diets seem very effective at helping people naturally reduce the number of calories they eat, resulting in weight loss.

Vegan diets, blood sugar, and type 2 diabetes

Adopting a vegan diet may help keep your blood sugar in check and type 2 diabetes at bay.

Several studies show that vegans benefit from lower blood sugar levels, higher insulin sensitivity, and up to a 78% lower risk of developing type 2 diabetes than non-vegans ( 14 , 15 , 16 , 17 ).

In addition, vegan diets reportedly lower blood sugar levels in people with diabetes up to 2.4 times more than diets recommended by the ADA, AHA, and NCEP ( 5 , 6 , 18 ).

Part of the advantage could be explained by the higher fiber intake, which may blunt the blood sugar response. A vegan diet’s weight loss effects may further contribute to its ability to lower blood sugar levels ( 4 , 6 , 9 , 10 ).

Summary Vegan diets seem particularly effective at improving markers of blood sugar control. They may also lower the risk of developing type 2 diabetes.

Vegan diets and heart health

A vegan diet may help keep your heart healthy.

Observational studies report that vegans may have up to a 75% lower risk of developing high blood pressure and 42% lower risk of dying from heart disease ( 16 , 19 ).

Randomized controlled studies — the gold standard in research — add to the evidence.

Several report that vegan diets are much more effective at reducing blood sugar, LDL (bad) cholesterol, and total cholesterol than diets they are compared with ( 4 , 5 , 9 , 20 , 21 ).

These effects could be especially beneficial since reducing blood pressure, cholesterol, and blood sugar may reduce heart disease risk by up to 46% ( 22 ).

Summary Vegan diets may improve heart health. However, more high quality studies are needed before researchers can draw strong conclusions.

Other health benefits of vegan diets

Vegan diets are linked to an array of other health benefits, including benefits for:

• Cancer risk. Vegans may benefit from a 15% lower risk of developing or dying from cancer ( 20 ).
• Arthritis. Vegan diets seem particularly effective at reducing symptoms of arthritis such as pain, joint swelling, and morning stiffness ( 23 , 24 , 25 ).
• Kidney function. People with diabetes who substitute meat for plant protein may reduce their risk of poor kidney function ( 26 , 27 , 28 , 29 , 30 , 31 ).
• Alzheimer’s disease. Observational studies show that aspects of the vegan diet may help reduce the risk of developing Alzheimer’s disease ( 32 , 33 ).

That said, keep in mind that most of the studies supporting these benefits are observational. This makes it difficult to determine whether the vegan diet directly caused the benefits.

Randomized controlled studies are needed before researchers can make strong conclusions.

Summary A vegan diet is linked to several other health benefits. However, more research is needed to determine whether the diet was a direct cause of those benefits.

Foods to avoid

Vegans avoid eating any animal foods , as well as any foods containing ingredients that come from animals . These include:

• Meat and poultry: beef, lamb, pork, veal, horse, organ meat, wild meat, chicken, turkey, goose, duck, quail, etc.
• Fish and seafood: all types of fish, anchovies, shrimp, squid, scallops, calamari, mussels, crab, lobster, etc.
• Dairy: milk, yogurt, cheese, butter, cream, ice cream, etc.
• Eggs: from chickens, quails, ostriches, fish, etc.
• Bee products: honey, bee pollen, royal jelly, etc.
• Animal-based ingredients: whey, casein, lactose, egg white albumen, gelatin, cochineal or carmine, isinglass, shellac, L-cysteine, animal-derived vitamin D3, and fish-derived omega-3 fatty acids

Summary Vegans avoid consuming any animal flesh, animal byproducts, or foods containing an ingredient from animal origin.

Foods to eat

Health-conscious vegans substitute animal products with plant-based replacements , such as:

• Tofu, tempeh, and seitan. These provide a versatile protein-rich alternative to meat, fish, poultry, and eggs in many recipes.
• Legumes. Foods such as beans, lentils, and peas are excellent sources of many nutrients and beneficial plant compounds. Sprouting, fermenting, and proper cooking can increase nutrient absorption ( 34 ).
• Nuts and nut butter. Unblanched and unroasted varieties are good sources of iron, fiber, magnesium, zinc, selenium and vitamin E ( 35 ).
• Seeds: Hemp, chia, and flaxseeds contain a good amount of protein and beneficial omega-3 fatty acids ( 36 , 37 , 38 ).
• Calcium-fortified plant milk and yogurt. These help vegans achieve their recommended dietary calcium intake. Opt for varieties also fortified with vitamins B12 and D whenever possible.
• Algae. Spirulina and chlorella are good sources of complete protein. Other varieties are great sources of iodine.
• Nutritional yeast. This is an easy way to increase the protein content of vegan dishes and add an interesting cheesy flavor. Pick vitamin B12-fortified varieties whenever possible.
• Whole grains, cereals, and pseudocereals. These are a great source of complex carbs, fiber, iron, B vitamins, and several minerals. Spelt, teff, amaranth, and quinoa are high protein options ( 39 , 40 , 41 , 42 ).
• Sprouted and fermented plant foods. Ezekiel bread, tempeh, miso, natto, sauerkraut, pickles, kimchi, and kombucha often contain probiotics and vitamin K2. Sprouting and fermenting can also help improve mineral absorption ( 34 , 43 ).
• Fruits and vegetables. Both are great foods to increase your nutrient intake. Leafy greens such as bok choy, spinach, kale, watercress, and mustard greens are particularly high in iron and calcium.

Summary These minimally processed plant foods are great additions to any vegan refrigerator or pantry.

Risks and how to minimize them

Favoring a well-planned diet that limits processed foods and replaces them with nutrient-rich ones is important for everyone, not only vegans.

That said, those following poorly planned vegan diets are particularly at risk of certain nutrient deficiencies.

Studies show that vegans are at a higher risk of having inadequate blood levels of vitamin B12, vitamin D, long-chain omega-3s, iodine, iron, calcium, and zinc ( 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 ).

Not getting enough of these nutrients is a concern for everyone, but it may pose a particular risk to those with increased requirements, such as children or people who are pregnant or nursing.

Your genetic makeup and the composition of your gut bacteria may also influence your ability to derive the nutrients you need from a vegan diet.

One way to minimize the likelihood of deficiency is to limit the amount of processed vegan foods you consume and opt for nutrient-rich plant foods instead.

Fortified foods, especially those enriched with calcium, vitamin D, and vitamin B12, should also make a daily appearance on your plate.

Vegans wanting to enhance their absorption of iron and zinc should try fermenting, sprouting, and cooking foods ( 34 ).

Also, the use of iron cast pots and pans for cooking, avoiding tea or coffee with meals, and combining iron-rich foods with a source of vitamin C can further boost iron absorption ( 57 ).

The addition of seaweed or iodized salt to your vegan diet can help you reach the recommended daily intake of iodine ( 58 ).

Lastly, foods containing omega 3s, especially those high in alpha-linolenic acid (ALA), can help the body produce longer-chain omega-3s, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) .

Foods high in ALA include chia, hemp, flaxseeds, walnuts, and soybeans. However, there’s debate regarding whether this conversion is efficient enough to meet daily needs ( 59 , 60 ).

A daily intake of 200–300 mg of EPA and DHA from an algae oil supplement may be a safer way to prevent low levels ( 61 ).

Summary Vegans may be at an increased risk of certain nutrient deficiencies. A well-planned vegan diet that includes nutrient-rich whole and fortified foods can help provide adequate nutrient levels.

Supplements to consider

Some vegans may find it difficult to eat enough of the nutrient-rich or fortified foods above to meet their daily requirements.

In this case, the following supplements can be particularly beneficial:

• Vitamin B12. Vitamin B12 in cyanocobalamin form is the most studied and seems to work well for most people ( 62 ).
• Vitamin D. Opt for D2 or vegan D3 forms, such as those manufactured by Nordic Naturals .
• EPA and DHA. These are sourced from algae oil.
• Iron. You should only supplement with iron in the case of a documented deficiency. Ingesting too much iron from supplements can cause health complications and prevent the absorption of other nutrients ( 63 ).
• Iodine. Take a supplement or add 1/2 teaspoon of iodized salt to your diet daily.
• Calcium. Calcium is best absorbed when taken in doses of 500 mg or less at a time. Taking calcium at the same time as iron or zinc supplements may reduce their absorption ( 57 , 64 ).
• Zinc. This is taken in zinc gluconate or zinc citrate forms and should not be taken at the same time as calcium supplements ( 64 ).

Summary Vegans unable to meet their recommended nutrient intakes through foods or fortified products alone should consider taking supplements.

A vegan sample menu for 1 week

To help get you started, here’s a simple plan covering a week’s worth of vegan meals:

• Breakfast: vegan breakfast sandwich with tofu, lettuce, tomato, turmeric, and a plant-milk chai latte
• Lunch: spiralized zucchini and quinoa salad with peanut dressing
• Dinner: red lentil and spinach dal over wild rice
• Breakfast: overnight oats made with fruit, fortified plant milk, chia seeds, and nuts
• Lunch: seitan sauerkraut sandwich
• Dinner: pasta with a lentil Bolognese sauce and a side salad
• Breakfast: mango and spinach smoothie made with fortified plant milk and a banana-flaxseed-walnut muffin
• Lunch: baked tofu sandwich with a side of tomato salad
• Dinner: vegan chili on a bed of amaranth
• Breakfast: whole grain toast with hazelnut butter, banana, and a fortified plant yogurt
• Lunch: tofu noodle soup with vegetables
• Dinner: jacket sweet potatoes with lettuce, corn, beans, cashews, and guacamole
• Breakfast: vegan chickpea and onion omelet and a cappuccino made with fortified plant milk
• Lunch: vegan tacos with mango-pineapple salsa
• Dinner: tempeh stir-fry with bok choy and broccoli
• Breakfast: spinach and scrambled tofu wrap and a glass of fortified plant milk
• Lunch: spiced red lentil, tomato, and kale soup with whole grain toast and hummus
• Dinner: veggie sushi rolls, miso soup, edamame, and wakame salad
• Breakfast: chickpea pancakes , guacamole and salsa, and a glass of fortified orange juice
• Lunch: tofu vegan quiche with a side of sautéed mustard greens
• Dinner: vegan spring rolls

Remember to vary your sources of protein and vegetables throughout the day, as each provides different vitamins and minerals that are important for your health.

Summary You can eat a variety of tasty plant-based meals on a vegan diet.

How to eat vegan at restaurants

Dining out as a vegan can be challenging.

One way to reduce stress is to identify vegan-friendly restaurants ahead of time by using websites such as Happycow . Apps like VeganXpress and Vegman may also be helpful.

When dining in a nonvegan establishment, try scanning the menu online beforehand to see what vegan options they may have for you.

Sometimes, calling ahead of time allows the chef to arrange something especially for you. You can then arrive at the restaurant confident that you’ll have something hopefully more interesting than a side salad to order.

When picking a restaurant on the fly, make sure to ask about their vegan options as soon as you step in, ideally before being seated.

When in doubt, opt for certain ethnic restaurants that tend to have dishes that are naturally vegan or can be easily modified to become so. Mexican, Thai, Middle Eastern, Ethiopian, and Indian restaurants tend to be great options.

Once in the restaurant, try identifying the vegetarian options on the menu and asking whether the dairy or eggs can be removed to make the dish vegan.

Another easy tip is to order several vegan appetizers or side dishes to make up a meal.

Summary Being well prepared allows you to reduce stress when dining out as a vegan.

Healthy vegan snacks

Snacks are a great way to stay energized and keep hunger at bay between meals.

Some interesting, portable vegan options include:

• fresh fruit with a dollop of nut butter
• hummus and vegetables
• nutritional yeast sprinkled on popcorn
• roasted chickpeas
• nut and fruit bars
• chia pudding
• homemade muffins
• whole wheat pita with salsa and guacamole
• cereal with plant milk
• whole grain crackers and cashew nut spread
• a plant-milk latte or cappuccino
• dried seaweed snacks

Whenever you’re planning a vegan snack, try to opt for fiber- and protein-rich options, which can help keep hunger away.

Summary These portable, fiber-rich, protein-rich vegan snacks are convenient options to help minimize hunger between meals.

Frequently asked questions

Here are some frequently asked questions about veganism.

1. Can I only eat raw food as a vegan?

Absolutely not. Although some vegans choose to follow this type of vegan diet, raw veganism isn’t for everyone. Many vegans eat cooked food, and there is no scientific basis for you to eat only raw foods.

2. Will switching to a vegan diet help me lose weight?

A vegan diet that emphasizes nutritious, whole plant foods and limits processed ones may help you lose weight.

As mentioned in the weight loss section above, vegan diets tend to help people eat fewer calories without having to consciously restrict their food intake.

That said, when matched for calories, vegan diets are no more effective than other diets for weight loss ( 65 ).

3. What is the best milk substitute?

There are many plant-based milk alternatives to cow’s milk. Soy and hemp varieties contain more protein, making them more beneficial to those trying to keep their protein intake high.

Whichever plant milk you choose, ensure it’s enriched with calcium, vitamin D , and, if possible, vitamin B12.

4. Vegans tend to eat a lot of soy. Is this bad for you?

Soybeans are great sources of plant-based protein. They contain an array of vitamins, minerals, antioxidants, and beneficial plant compounds that are linked to various health benefits ( 66 , 67 , 68 , 69 , 70 ).

However, soy may suppress thyroid function in predisposed individuals and cause gas and diarrhea in others ( 71 , 72 ).

It’s best to opt for minimally processed soy food products such as tofu and edamame and limit the use of soy-based mock meats.

Fermented soy products such as tempeh and natto are especially beneficial, as fermentation helps improve the absorption of nutrients ( 34 ).

5. How can I replace eggs in recipes?

Chia and flaxseeds are a great way to replace eggs in baking. To replace one egg, simply mix one tablespoon of chia or ground flaxseeds with three tablespoons of hot water and allow it to rest until it gels.

Mashed bananas can also be a great alternative to eggs in some cases.

Scrambled tofu is a good vegan alternative to scrambled eggs. Tofu can also be used in a variety of egg-based recipes, from omelets to frittatas and quiches.

6. How can I make sure I get enough protein?

Vegans can ensure they meet their daily protein requirements by including protein-rich plant foods in their daily meals.

Check out this article for a more in-depth look at the best plant protein sources.

7. How can I make sure I get enough calcium?

Calcium-rich foods include bok choy, kale, mustard greens, turnip greens, watercress, broccoli, chickpeas, and calcium-set tofu.

Fortified plant milk and juice are also a great way for vegans to increase their calcium intake.

The RDA for calcium is 1,000 mg per day for most adults and increases to 1,200 mg per day for adults over 50 years old ( 73 ).

Some argue that vegans may have slightly lower daily requirements because of the lack of meat in their diets. Not much scientific evidence can be found to support or negate this claim.

However, current studies show that vegans consuming less than 525 mg of calcium each day have an increased risk of bone fractures ( 55 ).

For this reason, vegans should aim to consume 525 mg of calcium per day at the very least.

8. Should I take a vitamin B12 supplement?

Vitamin B12 is generally found in animal foods. Some plant foods may contain a form of this vitamin, but there’s still debate about whether this form is active in humans ( 74 , 75 , 76 , 77 , 78 , 79 , 80 ).

Despite circulating rumors, there’s no scientific evidence to support unwashed produce as a reliable source of vitamin B12.

The daily recommended intake is 2.4 mcg per day for adults, 2.6 mcg per day during pregnancy, and 2.8 mcg per day while nursing ( 81 ).

Vitamin B12 fortified products and supplements are the only two reliable forms of vitamin B12 for vegans. Yet many vegans seem to fail to consume sufficient vitamin B12 to meet their daily requirements ( 82 , 83 , 84 ).

If you’re unable to meet your daily requirements through the use of vitamin B12 fortified products, you should consider taking a vitamin B12 supplement. A healthcare professional can help you decide if one is right for you.

The bottom line

Individuals may choose veganism for ethical, environmental, or health reasons.

The vegan diet can be easy to follow and may provide various health benefits.

As with any diet, though, these benefits only appear if you are consistent and build your diet around nutrient-rich plant foods rather than heavily processed ones.

Vegans, especially those who cannot meet their daily nutrient requirements through diet alone, should consider supplements.

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Why Go Vegan? The Top Reasons Explained

Why go vegan? The elevator pitch laying out the best reasons crams several compelling points into just a few seconds. It goes something like this:

A vegan lifestyle prevents a tremendous amount of animal slaughter and suffering. It offers a potent way to shrink our environmental footprint, especially in regard to climate change. And a well-planned vegan diet can fuel the highest levels of fitness, while reducing our risk of various chronic diseases. Plus, the food is insanely delicious and it becomes more plentiful every year.

The above sentences get us off to a nice start, but they don’t begin to do the subject justice. Indeed, getting up to speed on every important reason to go vegan would require months of reading. You would have to explore topics like plant-based nutrition, animal rights philosophy, and the exploitation of slaughterhouse workers. You’d also need to delve into the damage the meat industry inflicts on human health and the environment. There are dozens of other relevant subjects to consider, but you get the idea.

That said, we have to start somewhere. Learning the essentials doesn’t take long. This essay explains the strongest reasons to go vegan, and you can finish it in under an hour.

As we’re about to see, ridding your diet of animal products delivers remarkable benefits. You may never encounter a topic more worthy of your attention.

Defining a Vegan Diet

Vegan diets exclude all foods produced by or derived from animals: meat, fish, dairy products, eggs, and honey. Conversely, you can define veganism as a diet based entirely on plants.

Many vegans go beyond diet to remove animal exploitation from their entire lifestyle. They’ll avoid clothing made of wool and won’t buy leather furniture. Nor will they visit zoos or purchase cosmetics tested on animals. While such steps deserve consideration, to keep this essay concise I will focus entirely on diet.

The Virtues of Plant-Based Diets

Even if this essay doesn’t persuade you to go vegan, it may inspire you to gravitate toward a “plant-based” diet. While vegan diets exclude all animal products, plant-based diets offer some wiggle room. If you see the appeal of going vegan but don’t feel gung ho about it, plant-based diets offer an easily-reached middle ground.

Pretty much every food politics writer worth taking seriously—including Michael Pollan, Mark Bittman, and Eric Schlosser—advocates diets based heavily on plants. All it takes to go plant-based is to make a point of eating vegan foods whenever convenient. You can follow a primarily plant-based diet and still eat Thanksgiving turkey or a summer barbecue.

Perhaps the best reason to go plant-based relates to the lack of a sensible counterargument. In all my years of writing about food politics, I’ve never once seen anyone (other than a few paleo diet fanatics) deny the advantages of eating mostly plants. Eating more fruits and vegetables can significantly reduce risk of chronic disease . And of course, plant-based diets also keep farm animals from slaughter, while simultaneously protecting the environment.

Shifting to a plant-based diet often initiates a virtuous cycle. By eating plant-based, you’ll inevitably discover one healthy and delicious food after another. And that will in turn trigger a cascade of positive dietary changes.

The Joy of Exploring Plant-Based Foods

All it takes to eat plant-based is to regularly try new vegan foods. Inevitably, you’ll discover delicious possibilities that will become part of your everyday diet. So, as time goes by, your diet may become predominantly vegan without any concerted effort on your part. Plenty of current vegans transitioned by sliding down the plant-based slope.

A number of cute neologisms can inspire easy-yet-meaningful commitments: reducetarian , flexitarian , chegan , plant-strong , and even veganish . If any of these terms resonates with you, just grab ahold of it and start thinking along those lines.

Several other related concepts might also encourage you to eat more plant-based meals, including: Meatless Mondays , Mark Bittman’s Vegan Before 6:00 plan, or trying out a vegan diet for a week or a month.

Why Go Beyond Plant-Based?

Plant-based diets make all kinds of sense, but let’s also consider the advantages of going further and becoming vegan. When you eat vegan, you slam the door shut on countless disagreeable things—especially animal suffering.

Animal Cruelty in Agribusiness

Like vegans, most meat eaters recoil from animal cruelty and consider it abhorrent. Unfortunately, extraordinary cruelties occur throughout the meat, dairy and egg industries. And slaughterhouses—even the few that adhere to the best standards—are invariably horrifying.

Countless vegans spent decades blissfully devouring meat and other animal products until, one day, they encountered a slaughterhouse video. Just a minute or two spent watching any of these videos can inspire lifelong dietary change.

Writing cannot adequately convey the horrors of industrialized animal slaughter—the more detailed and accurate the written description, the more overwrought and implausible it sounds. So to truly understand what happens at slaughterhouses, you must actually witness the killing, rather than merely read about it.

Modern slaughterhouses kill and butcher animals at breakneck speeds. One Tyson Foods facility in Indiana produces three million pounds of pork every day.  YouTube hosts dozens of videos showing the slaughter of every type of farm animal. Many people can only last a few seconds before turning away. But what happens to animals is right there for everyone to see, for anyone willing to look. If we’re going to eat meat, don’t we each share an ethical obligation to see for ourselves how it’s produced?

If you oppose violence, a vegan lifestyle deserves your careful consideration . Nothing that follows can adequately describe the realities of a slaughterhouse, but I can at least lay out the essentials. Cows, pigs, and chickens are each slaughtered using different methods. We’ll start by considering how these animals are stunned prior to slaughter.

Cattle and Pig Stunning

When a beef or dairy cow steps onto the kill floor, a worker puts a captive bolt pistol to the animal’s forehead. The trigger pulled, a steel rod shoots through her skull, instantly inflicting a massive brain injury. A chain then hoists the cow into the air, and another worker cuts her throat. Over the following minutes she bleeds out as her still-pumping heart gushes blood onto the floor.

Although horrifying to witness, captive bolts are the least inhumane slaughterhouse stunning method.

Some pig slaughterhouses also use captive bolts, but many instead render the animals unconscious with carbon dioxide, a gratuitously inhumane practice . Videos taken at these facilities show panicked pigs desperately trying to push their snouts out of the carbon dioxide chamber to breathe fresh air. Still other pig slaughterhouses jolt the animals with electricity, which raises the question of whether the stunning adds to rather than diminishes total suffering.

Poultry Stunning

Chicken slaughter is especially heartless. Chicken producers say they stun their birds prior to slaughter, but they don’t, really. Their so-called “stunning” is actually done to speed up slaughter, and probably only compounds the birds’ misery. Let’s take a step back to look at what’s really going on.

In the United States, chickens are exempt from the Humane Slaughter Act. Anything goes, and the industry has no worries about facing cruelty prosecutions. The birds are hung upside down, with their feet inserted into steel shackles. They then whiz down the line at rates of at least 175 birds a minute . At three birds a second, chickens come down the line far too quickly for workers to be able to cut throats by hand , so it’s all done mechanically.

So how do you get a panicked, thrashing bird suspended upside down to relax her neck to be in proper position for the mechanical blade? That’s where the slaughterhouse’s “stunning” comes in. Just before reaching the blade, the chicken passes through an electrified water bath. The electric shock stuns the bird momentarily, just long enough for the head to hang limply to expose his throat to the blade.

If, however, the blade misses the neck, the chicken will be fully conscious a couple minutes later when he’s dropped into the tank of scalding water used to remove feathers from the carcasses of freshly-killed birds. Considering producers kill tens of billions of chickens a year worldwide, no doubt millions of these birds have scalded to death after a botched slaughter.

Kosher Slaughterhouses Don’t Stun

Not every farm animal is stunned prior to slaughter. Kosher and halal slaughterhouses refrain from stunning, since scripture requires the animals bleed out while fully conscious. This gives rise to all sorts of deeply disturbing slaughterhouse practices, as one hidden camera investigation after another has revealed.

Whether or not animals are stunned, the underlying reality remains constant: all meat comes from animals who arrived at the slaughterhouse desperately wanting to live. When unloaded from the trucks, every cow or pig invariably looks frantically about, seeking a direction to scramble to safety. But their only path forward leads to the blade.

I can’t say it any better than I did in my first book : “I have to believe the knife is as sharp to them as it is to us.”

The Fate of Layer Hens and Dairy Cows

Meat obviously necessitates slaughter, but so do milk and eggs. The only difference is that meat comes from animals who have been killed, whereas milk and eggs come from animals who will be killed, guaranteed.

Why slaughter perfectly healthy dairy cows and layer hens, who still have many years left to live? Because, as these animals age, their output sharply diminishes. By roughly one-third of their natural lifespan, milk and egg yields decline sufficiently to render the animals unprofitable. So they are killed and replaced by younger, more productive animals.

Slaughter methods for “spent” hens are especially troubling since the flesh is of low value or outright unsalable. Egg farms “depopulate” their hen-houses in particularly grisly ways, sometimes even asphyxiating the birds by spraying them with the sort of oxygen-absorbing foam found in fire extinguishers.

Crowding, Confinement, and Cruelty

As unsettling as slaughter is to contemplate, it’s only the starting point for considering the ethical issues surrounding animal agriculture. Most of the suffering that arises from meat, dairy, and egg production relates to how the animals are raised rather than how they are killed.

I know that thinking about animal suffering is extraordinarily unpleasant. It’s only natural to want to tune out the gory details. If you find yourself especially troubled by hearing about this awful stuff, perhaps that right there is the best reason of all to move towards a vegan diet.

As we’re about to see, factory farms carry out a multitude of indefensible cruelties. Each year, about 50 billion farm animals worldwide are subjected to the conditions I’m about to describe. ( Note 1 )

The human brain simply cannot wrap itself around the magnitude of a billion animals suffering, let alone 50 billion. To gain some sense of the scale of suffering we’re about to consider, here’s an innovative chart that assigns a tiny dot to each of the 1.6 billion chickens subjected to factory farm conditions at this moment in the United States.

The Inhumanity of Factory Farming

Animal advocates use the term, “factory farming” to refer to the dominant methods of animal production used in industrialized countries. While there are important differences between how cattle, pigs, and poultry are kept, most of these animals are raised at factory farms.

Prior to World War II, farm animals lived under comparatively good conditions on small, family-owned farms. They typically received reasonable amounts of space. And most had at least some access to sunlight and fresh air. So, they enjoyed largely acceptable conditions even if their lives were destined to be violently cut short. Farmers of that era didn’t provide this level of care out of the goodness of their hearts — they did it because mortality rates spiked to unprofitable levels when their animals’ basic living needs weren’t met. ( Note 2 )

The Great Depression and the Dust Bowl era ushered in massive changes to America’s system of agriculture. Land grant agriculture colleges across the United States pioneered new methods of farming both crops and animals. Starting in the 1930s, these colleges began teaching farming with the same rigor applied to scientific disciplines. And as a new generation of farmers studied subjects like chemistry and biology, everything about plant and animal farming changed.

The petrochemical-based “Green Revolution” that occurred from the 1930s to the 1960s massively increased crop yields. Standards of living improved worldwide while surging agriculture productivity doubtless averted numerous famines. But within animal agriculture, the new farming methods introduced during this period brought animal suffering to unconscionable extremes.

Meat, Milk, and Eggs Get Cheaper than Ever

The gigantic facilities that took over animal agribusiness are called “CAFOs” (Concentrated Animal Feeding Operations) by industry, and “factory farms” by activists. Factory farming created efficiencies that significantly decreased retail prices. People responded by eating more meat, milk, and eggs than ever before—while animal welfare standards simultaneously collapsed.

As meat, dairy, and egg production switched to factory farms, only facilities that slashed costs to the bare minimum could survive. Starting in the 1930s and continuing for more than a half century, thousands of meat, dairy, and egg producers went bust every year.

The dairy industry offers a prime example of the relentless financial pressure that farmers face. Between 1980 and 2020, the number of U.S. farms with at least ten dairy cows dropped by about 75 percent . In 2017, one regional dairy cooperative sent out suicide prevention letters after two of its members killed themselves. ( Note 3 )

To stay afloat financially, meat, dairy, and egg producers cut expenses wherever possible. That meant packing more animals into tighter spaces than ever before.

Crowding at Factory Farms

No farming cruelty exceeds those carried out by the egg industry . In countries and states that haven’t yet outlawed the practice, egg farms keep their hens in “battery cages” that provide less floor space per bird than a sheet of printer paper. These cages are too small to allow the hens normal movement or even to spread their wings. Worse yet, the flooring of these cages is widely-spaced metal rods. The hens sleep pressed against this rods or against the wire sides of their cages, commonly developing open sores and extensive bruising. They never enjoy a moment of comfort.

Here they remain confined with at least four other hens in this cage for the rest of their lives. And each egg they lay robs their skeleton of more calcium. One survey of “spent hens” revealed 85 percent have at least one broken bone.

Pigs are likewise kept under appalling living conditions. The sows kept to breed piglets have it especially bad, and often spend their entire lives in gestation and farrowing crates. Standard crates impede any sort of normal movement. In fact, they are so narrow that the sow lacks sufficient space to turn around.

What about cows and cattle? Whether in person or in movies, we’ve all seen cows grazing scenic hillsides. Beef cattle are the only farm animals that nearly always live the majority of their lives outdoors.

Although they graze freely outdoors for the first part of their lives, beef cattle are invariably “finished” at feedlots. There, they live out their final three or four months crowded onto filthy, barren plots of land.

One such feedlot is the notorious Harris Ranch that’s adjacent to Interstate 5 in Southern California. Having driven this stretch of Interstate countless times, I have often smelled the stench of the feedlot from several kilometers away. The feedlot covers a vast expanse of land, with long stretches crammed with animals amassed on black manure-coated earth. If you’ve seen one feedlot you’ve seen them all. Any large feedlot is indistinguishable from what you can see at Harris Ranch.

Conditions are comparably dreadful at many dairy farms. There are two kinds of confinement-oriented dairies. One kind keeps the cows under roofing, and chained in stalls. The other kind is nearly indistinguishable from beef feedlots, with the cows fenced onto land coated with blackened trampled manure.

Dairy calves raised at a massive veal operation. pic.twitter.com/FfD8S5Wu9A — no context viral (@nocontextviral) June 28, 2022

Intensively confined dairy cows have no opportunity to graze pasture, and are instead fed silage out of troughs. Twice a day, they’re herded indoors and hooked up to milking machines.

Mutilations at Factory Farms

Just as bullying and violence pervades poorly run schools and prisons, the same is true at factory farms. Extreme crowding incites aggressive behavior. The problem goes away if you provide adequate living space, but that’s an expensive remedy. Factory farms instead mutilate the animals in a variety of ways in order to keep them from injuring one another.

Pigs raised in crowded pens are apt to bite each others’ tails. Workers therefore cut the tails down to the nub and clip the “needle teeth.” While they’re at it, they also cut notches out of the animals’ ears for identification purposes.

Hens crammed into battery cages sometimes peck each other to death. So egg producers use a hot blade to sear off the pointy final third of their beaks—reducing the chances that a peck can draw blood. While a beak may appear woody on the outside, the hen’s mouth lies inside and is full of nerve endings. So beak searing entails a partial (and no doubt excruciatingly painful) amputation of the bird’s mouth. Some hens die after beak searing renders them unable to drink or eat.

In order to improve beef tenderness and also eliminate the “ boar taint ” stench in pork, male calves and piglets are castrated. I’ll spare you the details of how this is done, but interested readers can read this article or watch this video .

Unlike pigs and chickens, stressed out cattle don’t commonly attack one another. But ranchers do brand their cattle with a hot iron to prove ownership at auction. Some ranchers use a frozen iron that is just as permanent and probably just as cruel. At dairies, some farmers cut off their cows’ tails so they don’t interfere during milking.

Each of these mutilations, including castration, typically occurs without anesthesia. A local anesthetic would greatly reduce pain, but factory farm owners regard even the cheapest pain killers as prohibitively expensive.

Selective Breeding

Even when raised in good environments, farm animals commonly suffer from a variety of painful health problems. That’s because decades of selective breeding have boosted growth rates, egg output, and milk yields to staggering extremes . These breeding advances dramatically improve efficiency, but the animals pay a terrible price.

In one extreme example, a profoundly over-muscled breed of beef cow called the Belgian Blue is normally born via Cesarean section .

Early Deaths in Meat Chickens

No animal is more genetically revved up than chickens, and none suffers more as a result. Chickens raised for meat grow more than four times faster than their counterparts raised in the 1950s. ( Note 4 )   This rapid growth severely strains the birds’ cardiovascular system, and up to 4 percent of birds die from “sudden death syndrome.” Animal welfare organization Open Cages estimates that, in the UK alone, growth-related maladies prematurely kill more a million chickens every week.

Additionally, many chickens suffer from debilitating hip and leg problems brought on by their unnaturally fast growth. One large study found that more than 25 percent of meat chickens have trouble moving, with nearly 4 percent, “almost unable to walk.” Unable to access food or water, they die of thirst or starve to death. No one notices their plight or pauses to provide care—time is money, and chickens who are destined to die prematurely aren’t worth the attention.

Egg Industry Cruelties

Specialized facilities called hatcheries churn out the billions of chicks a year for the poultry industry. At hatcheries servicing egg companies, one unwanted male chick hatches for every female chick. These males have no value, since they aren’t of the breed that can grow profitably for meat. At some of these hatcheries the male chicks are tossed into garbage cans and left to smother. At others, newly-hatched males are ground up alive . In the United States alone, hatcheries kill about 200 million male chicks every year.

Just like every human pregnancy carries risk, complications can arise every time a hen lays an egg. Thanks to selective breeding, hens lay more eggs than ever before, and consequently face far more chances for something to go wrong. A common complication during egg laying is a “prolapse.” Here, the egg adheres to the hen’s internal organs, which will get pushed out during laying along with the egg.

Hens afflicted with a severe prolapse will suffer a lingering death from blood loss or infection. If they’re lucky, they’ll be noticed and discarded atop a pile of dead hens. But in most cases, they take their dying breaths trampled by cage-mates while lying pressed against their cage’s wire floor. In the United States alone, millions of hens die like this each year as a result of prolapses and other conditions. ( Note 5 )

Mastitis in Dairy Cows

Dairy cows likewise suffer numerous maladies brought on by selective breeding. Today’s cows may look the same as yesterday’s, but they produce over four times more milk per animal than did cows from 1950. ( Note 6 ) These extreme milk yields cause a variety of health problems, the most common of which is an infection of the udders known as mastitis. Udder infections dramatically increase the number of “somatic cells” in milk. Laypeople have a more plainspoken word for somatic cells. That word is “pus.”

Thanks to their unprecedented milk yields, mastitis is pervasive among dairy cows. So if you want to ensure your milk contains no pus, you must choose a plant-based variety like soy milk.

Undercover Farming Videos

I’ve written two books that examine farm animal welfare standards. Writing them convinced me that words cannot do justice to the topic. In order to truly grasp what the animals experience, you really must visit factory farms yourself. Of course, factory farm owners don’t want the public to witness what’s going on. Most of these places therefore forbid visitors. Thankfully, the world has people like my friend Cody Carlson.

Cody switched to a vegan diet at age nineteen. A few years later, he took a job at a large dairy farm in Upstate New York. He worked there for a month, then left to work in a pig-breeding facility in Pennsylvania. After that gig ended, he got jobs at two different egg farms. Cody’s choice of diet was not the only thing that set him apart from his coworkers. The other difference was that, each day when Cody arrived at the job, he wore a hidden camera.

What happens when you take people who lack decent employment opportunities, pay them low wages, and put them in stressful work environments with minimal supervision? All too often, they take out their frustrations on the animals. The atrocities that undercover investigators like Cody have uncovered at factory farms are endless. I’ve seen videos showing turkeys being sexually violated . I’ve witnessed mother cows punched in the face . I’ve watched animals kicked, jabbed with pitchforks , and laughed at while bleeding to death. I’ve even seen a worker strike a defenseless calf between the eyes with a pickaxe—on the orders of his boss. And all of this barely touches on the things that I’ve seen. I could go on and on with more examples.

Few jobs are as traumatizing as that of an undercover animal cruelty investigator. Yet many activists have stepped up to do this work. They’ve collectively shot hidden-camera videos at every type of animal farm, from chicken hatcheries to cattle feedlots to pig farms. Still other undercover investigators have taken jobs at slaughterhouses and fishing boats. No matter where these investigators show up, staggering cruelties reveal themselves.

YouTube hosts a vast assortment of undercover videos that expose the poultry and livestock industries’ unending cruelties. One video after another captures appalling conditions and sadistic behavior by workers.

Typically, whenever a new undercover video goes public, the guilty company clutches its pearls and promptly fires the workers caught abusing animals. While these firings are invariably well-deserved, they conveniently shift blame away from ownership. Yet the root of the problem is not with any individual worker. It’s invariably management that allows or even encourages these cruelties. Factory farms are owned and operated by people willing to inflict unfathomable suffering onto animals for the sake of cutting costs.

Ag-Gag Laws

For decades, the appalling cruelties inflicted onto farm animals remained hidden from public view. But in the early 2000s, advances in camera miniaturization enabled undercover videos like those shot by Cody Carlson. These videos pulled back the curtain on what happens every day at factory farms and slaughterhouses. Probably the most famous saying in TV journalism is, “If it bleeds, it leads,” and farm animal cruelty videos attracted news coverage on an unprecedented scale.

With top media outlets rushing to cover every new video, all of the top farm animal protection nonprofits hired undercover investigators. Groups like MFA , HSUS , and PETA collectively released dozens of videos showing the mistreatment suffered by cattle, pigs, chickens, turkeys, and sheep. Every new investigation could garner media coverage seen by millions of people.

All of this created an existential threat to animal agribusiness, which was unwilling to reform its heartless practices. Instead, industry lobbyists sought to outlaw the filming of undercover videos. The top farming states invariably have senior lawmakers receptive to carrying out the industry’s bidding. At lobbyists’ behest, they introduced a new type of legislation known as “ag-gag” laws.

These laws increase penalties for trespassing at factory farms and slaughterhouses, and forbid seeking employment at these places under false pretenses. After being enacted by several top U.S. agriculture states, these laws have since spread to Canada and Australia. Fortunately, ag-gag laws are consistently struck down by judges on constitutional grounds, but agribusiness lobbyists persistently work to reintroduce new variations.

In rural communities, large factory farms or slaughterhouses are often the county’s main employer and taxpayer, so these businesses wield substantial influence with their local District Attorneys. Ag-gag laws offer the perfect weapon to target animal advocates. District Attorneys often sadistically hang a lengthy prison sentence over an activist’s head, sometimes for years, only to abruptly drop the case a day or two before trial is set to begin. They commonly drop charges at the last minute to keep the law from being tested and overturned on constitutional grounds, so it’ll remain on the books to intimidate and discourage future activists. Often, by the time the case is dropped, the activists have spent tens of thousands of dollars in legal fees to prepare for a trial the DA had no intention of actually prosecuting.

So rather than having laws to protect farmed animals, we have laws targeting the people who work to expose animal cruelty. Perhaps it is only to be expected that an industry that brutalizes tens of billions of animals annually would also work to undermine essential human freedoms.

Camille Labchuck of the Canadian nonprofit Animal Justice sums up the situation: “Instead of holding farms accountable for widespread animal abuse, legislators in the U.S. and Canada are more focused on keeping farmed animal cruelty stories out of the nightly news.”

Common Farming Exemptions

Although Common Farming Exemptions (CFEs) get much less attention than ag-gag laws, they cause even greater harm to farm animals. Around the year 2000, these laws started to be passed by various farming states. The fact that they all appeared at roughly the same time and shared similar language suggests that national poultry and livestock interests were pulling the strings in a coordinated way.

When you first learn about battery cages, farrowing crates, and ventilation shutdown, it’s only natural to assume that there are animal cruelty laws that forbid these sorts of things. The point of CFEs is to exempt farm animals from even the most minimal protections from cruelty. The laws achieve this by stating that as long as a given farming, transport, or slaughter practice is common or customary, then it’s exempt from animal cruelty laws.

Attorney David Wolfson was the first person to perceive and write about the threat that CFEs pose to farm animals. He asserts that:

CFEs give complete power to the farming community to decide what is cruelty to a farmed animal. If the industry adopts a practice it automatically becomes legal, and farmers cannot be prosecuted for cruelty, no matter how horrific the practice. ( Note 7 )

According to the Humane Society of the United States, the majority of U.S. states have enacted CFEs.

Mass Casualty Events

Not every farm animal dies in a slaughterhouse. Millions each year die accidentally or deliberately in mass casualty events. These include barn fires, sinking ships, equipment failures, and ventilation shutdowns.

Fires. Poultry barns are so densely stocked that just one fire can kill more than 100,000 birds. The Animal Welfare Institute calculated that fires killed about 3 million animals between 2018 and 2021. Since then, a 2022 fire at a Minnesota egg farm killed 200,000 hens . And in 2023, 100,000 hens died in a fire in Connecticut. Also in 2023, and explosion caused a 2 million square foot Texas dairy burn to the ground, killing 18,000 cows . Sinking Ships. Just as chicken and livestock barns are prone to burst into flames, massive ships crammed with livestock commonly sink to the bottom of the ocean. In June of 2022, more than 15,000 sheep perished when an overladen transport ship bound for Saudi Arabia capsized. In 2020, a transport ship bound for Japan sank during a typhoon , drowning 6000 cattle and 40 crew members. In 2019, another transport ship overturned, and initially more than 13,000 sheep were believed to have drowned. Subsequent reporting revealed the ship had secret decks installed that likely contributed to its capsizing, and that thousands more sheep therefore drowned than originally thought.

Equipment Failures. Anytime large numbers of animals are confined, equipment glitches can cause mass fatalities. In 2023, a failure of the carbon dioxide filter system at a Canadian fish farm suffocated 100,000 salmon .

Ventilation Shutdown. When avian influenza outbreaks occur, authorities commonly order the immediate killing of every bird in the region. An avian influenza outbreak during the winter of 2021-22 caused the culling of 77 million chickens worldwide, including 38 million birds in the United States alone. To minimize labor costs, farmers often employ a shockingly barbaric killing method known as ventilation shutdown . Here, all fresh air is cut off, temperatures spike, and the animals cook to death. It’s like killing dogs by locking them in a car during a heat wave, only crueler, since the animals usually take three to four hours to die. Some farmers wheel propane heaters into the barns to hasten death.

Ventilation shutdowns were also used to kill thousands of pigs in 2020, when supply chain breakdowns arising from the COVID pandemic rendered farmers unable to transport animals to slaughter.

All the Edges Rough

Factory farms minimize expenses at every opportunity. These efforts play out in all sorts of distressing ways. No matter where in the system an animal may be, agonies and discomforts suffuse every moment. There is not one softer corner, nothing without an edge, no flicker of respite.

This essay is intended to be read in one sitting, and therefore lacks space to adequately explore the endless cruelties that occur within animal agribusiness. I haven’t room to talk about what happens to the hundreds of thousands of pigs and cattle injured during transport, who arrive at the slaughterhouse unable to walk. Nor can we linger here on the experiences of the dairy cows who watch their newborns taken away just a day or two after birth. We likewise lack space to reflect on the runt piglets who fail to grow profitably, and who are often killed by having their heads slammed against concrete . No book and certainly no essay can do the topic justice. Factory farms inflict every variety of torment onto the 50 billion of animals they raise annually.

A vegan diet slams the door shut on all this cruelty and abuse, while likewise delivering additional benefits concerning the environment and human health.

How Do Vegan Diets Protect the Public Health?

In addition to the personal health risks associated with eating meat, dairy, and eggs, the production of these foods brings significant risks to the public health. Factory farms create pathogenic microbes resistant to antibiotics, cause substantial air pollution, and continually expose humanity to risk of pandemic.

Antibiotic Use at Animal Farms

Animal agribusiness imposes all sorts of massive hidden costs onto society. Among the most worrisome is its constant incubation of new strains of antibiotic-resistant bacteria.

The meat and pharmaceutical industries share a common interest. Meat producers want unfettered access to huge quantities of antibiotics, while pharmaceutical companies want the cash these sales generate. When added to animal feed, antibiotics significantly boost growth rates while reducing disease arising from stress and overcrowding. So big meat and big pharma have teamed up to lobby the government to allow these antibiotic sales to continue, at great detriment to the public health.

Roughly 70 percent of the United States’ antibiotic supply is consumed by farm animals, a percentage that has steadily increased for years . Worldwide, the meat and dairy industries combine to use more than 100,000 tons of antibiotics per year .  Many of these antibiotics, like penicillin and tetracyclines, have irreplaceable uses in human medicine.

Confining thousands of animals in one space and dosing them all with antibiotics inevitably increases microbial resistance. This in turn renders important classes of antibiotics ineffective for urgent human medical needs. Although it’s difficult to definitively link the emergence of a lethal strain of antibiotic-resistant bacteria to a particular animal farm, there is no doubt that factory farms spawn an assortment of deadly bacteria like the MRSA superbug. A 2018 report from the Environmental Working Group found antibiotic-resistant bacteria contaminating the majority of beef, pork, and turkey samples.

Pandemic Risks Connected to Animal Agribusiness

Each year, humans raise and slaughter more than 50 billion chickens and 750 million pigs . Confined to factory farms in every corner of the earth, these animals create a vast reservoir enabling influenza viruses to mutate into new and deadlier strains.

So-called “seasonal flu” viruses don’t come out of nowhere; they invariably trace back to pigs and birds . A typical winter’s flu kills about 400,000 people from respiratory failure. When a given year’s outbreak comes from birds, it may never be determined whether the virus originated from wildlife or if the world’s chicken industry is to blame. But when “swine flu” is the dominant strain, the pork industry is invariably responsible. The 2009 swine flu outbreak killed an estimated 284,000 people.

However deadly, in one important respect a typical flu season signifies a catastrophe averted. That’s because each year factory farms risk spawning a pandemic equal or worse than that triggered by COVID-19. All it takes is an especially deadly and transmissible viral mutation occurring in one chicken or pig to set off a worldwide pandemic.

In any given year, the possibility of a worst-case scenario is remote. But when farms raise tens of billions of chickens and pigs annually for decades on end, one day our luck is likely to run out.

If and when disaster strikes, humanity will pay an immense price. And we can bet that factory farms will, as usual, evade responsibility for having recklessly risked the lives of millions.

How do Vegan Diets Protect the Environment?

Vegan diets carry a number of environmental and public health advantages. These include:

• Enabling more people to be fed using less farmland
• Substantially reducing air and water pollution
• Reducing greenhouse gas emissions that contribute to climate change
• Encouraging improved biodiversity

A 2023 study published by Nature looked into all these matters and found that, in each of these respects, a vegan diet tended to be superior to vegetarian and non-vegetarian diets.

Let’s briefly look into each of these topics.

Reducing the Need for Farmland

Written by Frances Moore Lappé in 1971, Diet for a Small Planet was the most influential food politics book of its generation. Through her writing, Lappé awakened the public to the merits of eating lower on the food chain. That means basing your diet primarily on plants, rather than on animals who in turn eat plants. Diet for a Small Planet was the first bestseller to explore how plant-based diets can shrink your environmental footprint.

Lappé revealed the extraordinarily inefficiencies connected to animal farming. She documented how feeding grain to poultry and livestock wastes tremendous amounts of food energy, protein, and other nutrients. On a planet racked by crop failures and famine, Lappé argued that it’s depraved to squander our food resources on meat production. Decades of subsequent research confirms the book’s thesis. For instance, a 2018 study determined that replacing all meat, dairy products, and eggs with vegan choices could feed an additional 350 million people .

Air Pollution Associated with Animal Agribusiness

Factory farms generate staggering amounts of air pollution.

A 2023 study in Nature considered three greenhouse gases: methane, nitrous oxide, and carbon dioxide. It found that, compared to omnivorous diets, vegan diets reduced diet-related climate change impact by about 75 percent.

Then there are the dense and noxious air pollutants that, rather than enter the upper atmosphere, stay localized and harm the health of people living nearby.

On this topic, the pork industry deserves special mention. Pig urine tends to create substantial amounts of airborne ammonia when evaporated. The air inside pig barns is consequently so noxious that many pigs develop lung lesions . Workers, too, have significantly elevated rates of respiratory problems. People living on properties adjacent to pig farms are likewise prone to impaired lung function .

In addition to ammonia, factory farms generate many other types of airborne pollutants that harm the public health. A 2021 study published in the Proceedings of the National Academy of Sciences determined that upwards of 13,000 Americans die each year from air pollution generated by meat, dairy, and egg producers.

Water Pollution from Poultry & Livestock

In addition to its inefficient use of resources, the pollution emitted by factory farms is a serious menace in its own right.

Cattle, pigs, and chickens produce mountains of manure. Even though this waste makes outstanding fertilizer, its high water content makes manure too heavy and therefore too expensive to truck to distant farmlands to fertilize crops.

So instead of putting it to productive use as fertilizer, factory farms usually get rid of their manure by spraying it onto surrounding fields, often at levels that go far beyond any legitimate need for fertilization. Predictably, this method of disposal tends to foul local water supplies, especially well-water.

Factory farms often store raw animal waste in “lagoons,” where it slowly decomposes. Flooding from heavy rains commonly washes this waste into rivers, fouling water supplies downstream. In the United States, much of this runoff ends up in the Gulf of Mexico, with dire consequences. The massive influx of nitrates and phosphates causes algal blooms that create vast oxygen-free “dead zones.” The size and locations of the Gulf’s dead zones vary according to the season and the weather, but average more than 15,000 square kilometers . Whenever these dead zones drift into new territory, virtually all fish and other marine life suffocate . The Chesapeake Bay, which is ringed by a large portion of America’s poultry farms, experiences problems comparable to what occurs in the Gulf of Mexico.

The problems afflicting the Gulf of Mexico and the Chesapeake Bay are, according to New Scientist , playing out internationally : “The amount of nitrogen pollution emitted just by global livestock farming is more than the planet can cope with, prompting scientists to say we need to eat less meat and dairy produce.”

Animal Agriculture’s Contribution to Climate Change

What is possibly the strongest environmental reason to adopt a plant-based diet only emerged relatively recently. Animal agribusiness stands a leading emitter of greenhouse gases.

The 74 billion farm animals raised worldwide each year collectively spew massive amounts of methane into the atmosphere. Methane is a potent greenhouse gas that traps at least thirty times more atmospheric heat than an equal amount of carbon dioxide. Beef and dairy cattle are especially problematic, since as ruminants they generate substantially more methane per calorie of food produced than do pigs or poultry.

Estimates vary regarding the percentage of climate change attributable to animal agriculture, but a comprehensive United Nations study pegged the industry’s contribution to the problem at about 14.5 percent .

Over the past few decades, improved efficiencies in livestock production have decreased emissions per animal. But regardless, animal agriculture is still a top of greenhouse gas emitter—and certainly ranks among the easiest sources of greenhouse gases to curtail. For years, the beef industry has claimed it could eventually solve the methane problem using feed additives, often citing seaweed as an ingredient holding particular promise. But a 2023 study found seaweed’s results fell well short of the hype .

So there’s no magic bullet by which animal agribusiness can solve its methane problem. Society can’t do away with gasoline and diesel powered vehicles overnight, nor can we abruptly convert to carbon-free sources of electricity. But switching to a plant-based diet is easy, and can deliver superior nutrition at lower cost. Plant-based diets therefore deserve recognition as the most realistic opportunity to rapidly cut greenhouse gas emissions.

Dr. Michael Clark, A leading researcher on the connection between food and climate change, writes :

The good news is, there are many achievable ways rapidly to reduce food emissions if they are acted on quickly. These include both raising crop yields and reducing food loss and waste, but the most important is for individuals to shift towards predominantly plant-based diets.

Vegan Diets Are Linked to Improved Biodiversity

Simply because you can feed more people with less land, populations embracing vegan diets will naturally allow vast tracts of farmland to revert back to nature, thereby increasing both plant and wildlife biodiversity. Vegan diets also reduce reliance on monocultured feed crops, which make heavy use of herbicides, pesticides, and petroleum-based fertilizers.

The ranching industry in particular is well-known for killing large numbers of wildlife. In fact, an entire division within the USDA, ironically named “Wildlife Services,” devotes itself largely to killing off wildlife in response to complaints made by cattle and sheep ranchers. In 2021, Wildlife Services killed 1.75 million animals .

Factory Farming’s Five Strategies

How does animal agribusiness stay profitable, while getting away with all the harm it inflicts onto people, animals, and the environment? The industry shows remarkable ability to profit while shielding itself from regulation and litigation. This success comes from focusing on these five priorities:

• Breeding programs. Thanks to a century of selective breeding programs, today’s meat animals grow remarkably quickly. Dairy calves and layer hens likewise produce unprecedented yields of milk and eggs. Growth and productivity is further boosted through the use of antibiotics and hormones.
• Maximizing stocking density. Although it causes immense harm to animal welfare, raising animals in crowded conditions plays a key role in reducing costs. Additionally, animals are packed tightly onto trucks or ships when sent to slaughter.
• Automation. A variety of technologies and equipment cuts labor costs at every turn. These include milking machines and feeding animals via conveyor belt. Slaughterhouse lines likewise run at high speeds to maximize productivity.
• Exploiting workers. The meat industry has a long history of recruiting foreign undocumented workers who work for low pay, and are unlikely to unionize.
• Lobbying. The writing and passage of ag-gag and common farming exemption laws represents only a portion of agribusiness’ lobbying efforts. Whether it’s derailing environmental and animal welfare regulations or convincing the USDA to subsidize cheese production and slaughterhouse construction , animal agribusiness lobbyists are adapt at gaining preferential treatment for their industry. In particular, lobbyists have had remarkable success enacting laws that prevent homeowners from suing over quality of life nuisances. And since factory farms are often the main employer in rural communities, they consistently push local district attorneys to go after undercover investigators who expose and publicize animal cruelty.

Taken together, these strategies have made animal agribusiness huge, profitable, ruthlessly exploitative, and largely unaccountable for its wrongdoings.

Why Not Just Avoid Factory Farmed Foods?

Unless specifically labeled to the contrary, you can assume that every non-vegan food you purchase comes from a factory farm. As we’ve seen, an unending variety of cruelties occur at these places.

Millions of omnivores have pushed back against factory farming by demanding higher animal welfare standards. Most natural foods stores and supermarkets sell specially-labeled animal products from farms that promise better animal welfare. Additionally, small-scale meat, milk, and egg producers run booths at thousands of local farmers’ markets.

At their best, these smaller farms deliver genuine animal welfare improvements. That’s mainly because they refuse to partake in the cruelest farming practices, particularly with regard to confinement and crowding. And with this reduced crowding, farmers can eliminate mutilations like beak searing and tail-clipping. That’s because animals raised under good conditions rarely attack or bully one another.

Unfortunately, the substantial price premium commanded by higher welfare foods exerts an overpowering temptation on producers to cheat. Few other businesses offer so much incentive to deceive with such little risk of getting caught. All too often, farmers exaggerate or outright lie about standards for animal care. Just like at factory farms, every small-scale producer faces the strongest financial temptation to push limits. Since the cost of delivering genuinely good animal welfare is so high, there are always competitors willing to cut corners.

In fact, some so-called “organic” farms are actually factory farms in every sense of the word. While they may use higher quality animal feed and refrain from using antibiotics, animal welfare remains deplorable. At one point, several of America’s largest “organic” dairies exploited a regulatory loophole that allowed them to keep their cows confined indoors 310 days out of every year. In 2022, organic milk giant Fairlife agreed to pay $21 million in damages for false advertising, after an animal rights group released shocking videos exposing Fairlife’s cruel treatment of cows.

Animal Welfare Certification Programs

To avoid breaches of trust, food service companies and groceries rely on a variety of animal welfare certification programs. Much like hotels are typically rated from one to five stars, one leading program offers five different tiers of animal welfare. That way, at least in theory, the consumer can decide for herself which animal husbandry practices are acceptable, and choose products accordingly.

Of course, every welfare certification system depends on farmers living up to their promises. For these programs to succeed in their mission, it’s imperative that they quickly catch any farmers who cheat. This in turn demands careful monitoring and strict enforcement by the certification agency. It’s fair to say that, in the real world, such monitoring is expensive, occasional, and unreliable.

Checking Up on Your Local Farms

Alternately, you can do your own monitoring. This requires meeting the sellers of animal products at your local farmers’ market, and then personally visiting their farms to evaluate the conditions. Me, I have better things to do with my time. I don’t want to spend my precious Saturday afternoons driving out to distant farms. Much easier, I think, to simply avoid foods where egregious abuses of consumer trust and animal welfare are commonplace.

In this respect, laziness surely ranks as one of the most underappreciated reasons to consider a vegan diet. You undoubtedly have more pleasant ways to spend your time than investigating animal welfare compliance. And why expend all that effort when there exists such an abundance of delicious vegan food?

Animal Exploitation that Can’t be Remedied

In any case, no matter how you may strive to purchase only the highest-quality animal products, numerous problems remain unaddressed. As just one example, there is simply no way to eliminate slaughter. Even the highest-welfare producers kill their dairy cows and layer hens well before midlife, as yields decline. What’s more, many farms are legally prohibited from slaughtering their animals on-site. So, much of the time, “free-range” and “pasture-raised” animals end up at the very same slaughterhouses that kill factory farmed animals.

Diving a little deeper, the use of heirloom breeds is all but unheard of in commercial agriculture. So even at the very best “pasture raised” farms, the animals suffer the same breed-related health problems as their factory-farmed counterparts.

In short: the more you care about sourcing animal products free of needless suffering, the messier and more unsatisfying your task becomes.

Counter-intuitively, it’s therefore not vegans but omnivores who face the greatest inconvenience when it comes to conscientious eating. Instead, it’s omnivores who must confront a barrage of tasks and expenses if they are to ensure acceptable welfare standards. By contrast, aspiring vegans have it much easier—their primary task is to seek out delicious new foods .

A Word About Seafood

Most vegan-related writing doesn’t devote much space to seafood, or else ignores the topic entirely. For people moving in a vegetarian direction, fish is typically the last food to go.

But there are strong reasons to avoid seafood. You can even make the case that seafood is among the most problematic of animal products. This is especially true for crabs and lobsters, since these animals are killed by being boiled alive. All evidence suggests their suffering is excruciating. ( Note 8 )

Can Fish Suffer?

What about fish caught by nets or fishing lines? Are they capable of suffering? And, if so, how severely?

Studies definitively prove that fish can feel pain. They usually die by suffocation, and deep water fish die a particularly agonizing death—as they’re pulled to the surface, their eyes bulge out and organs rupture from depressurization.

The Environmental Cost of Fishing

Thanks to the world’s insatiable appetite for seafood, the fishing industry ranks among the planet’s great environmental menaces. Since 1960, the amount of seafood pulled daily from the world’s oceans, rivers, and lakes has more than tripled .

As a result, fish populations are in steep decline . There simply isn’t enough fish to go around, despite the fact that populations in some regions utterly depend on fish for survival. With all this in mind, if people must eat seafood, perhaps it should be reserved for populations that would face hunger without it.

Enforcing regulations against over-fishing poses intractable problems. Fishing boats commonly switch off their electronic tracking equipment to evade the enforcement of catch limits. Even when reliable monitoring programs are implemented, all too often regulators do too little too late. One prime example involves the waters off Newfoundland, which were once among the world’s most abundant cod fisheries. While authorities dickered and delayed, over-fishing so ravaged the ecosystem that the cod forever vanished .

Fishing fleets decimate not just targeted fish, but every sort of marine life. The world’s fishing boats are constantly pulling thousands of kilometers of nets through the sea. These nets ensnare every sort of animal, suffocating countless dolphins, sea turtles, sharks, and even seabirds. Some shrimp boats haul in 4 to 6 kilograms of marine life for every kilogram of shrimp.

Fish farms are no solution to over-fishing, and in fact exacerbate the strain on ocean resources.

What’s more, the crowding and welfare standards at fish farms are every bit as reprehensible as at any factory farm. Fish farms commonly suffer infestations of gruesome parasites called sea lice . These parasites attach themselves to the fish and eat away at the skin, causing open lesions.

Genetic modification, which is carried out to increase growth rates, causes deformities and even deafness among farmed salmon. Perhaps most disturbing, these fish routinely escape into the open ocean where they mate with wild fish . This interbreeding corrupts the gene pool of native salmon species, who are already threatened by over-fishing.

Animal Welfare & Animal Rights

Now that we’ve seen how brazenly the food industry exploits both farm animals and marine life, let’s consider how to address the problem. The two fundamental concepts of the animal protection movement— animal welfare and animal rights —offer powerful approaches.

Defining Animal Welfare

Animal welfare is a simple but potent concept inseparable from common decency. Its core message is: if you’re going to use animals for food, cosmetics, or anything else, you are morally obligated to eliminate needless suffering. Unfortunately, that’s easier said than done. A great deal of the suffering that stems from raising animals for food is expensive and difficult to eradicate. It’s also tricky to verify that farmers comply with welfare standards, since—as we’ve seen—they have strong incentive to cheat.

Animal welfare concerns inspire some people to go vegan, and others to switch to pasture-raised alternatives. Many omnivores who carefully think about animal welfare decide they can’t make peace with slaughter. Opposing the killing of animals doesn’t just close the door on consuming meat, it also rules out eggs and dairy products, since virtually all layer hens and dairy cows go to slaughter as well.

Defining Animal Rights

The animal protection movement’s most important ideas relate not to animal welfare, but to animal rights. Animal welfare condones the use of animals, as long as we attempt to minimize suffering. Animal rights, by contrast, asserts that animals do not exist for our use. Just as it’s wrong to falsely imprison somebody, even if the prison cell is clean and spacious, animal rights thinking contends that raising animals for food is wrong regardless of whether the animals receive decent care.

Animal rights books commonly introduce three crucial concepts: speciesism, subject of a life, and utilitarian thinking. Together, they address the “why go vegan?” question with some exceptionally clear thinking.

Speciesism is the simplest and most widely-used idea within animal rights. This word denotes attempts to justify exploitation based on an animal’s species. Such rhetoric inevitably ignores more pertinent facts. The question of whether rights are unjustly violated should start by evaluating each individual animal’s ability (or lack thereof) to think, feel, and suffer.

When an animal’s rights are violated, speciesist thinking is often to blame. An obvious example relates to the fact that, by all accounts, pigs are more intelligent than dogs. Yet the pork industry’s standard farming practices would generate a stream of felony cruelty convictions if it treated dogs in the same manner.

Speciesism is cut from the same cloth as racism, sexism, and classism. All of these “isms” violate an individual’s liberties on grounds that are fundamentally arbitrary. The only thing that sets speciesism apart from the others is that it provides an excuse to exploit certain types of animals rather than certain groups of people.

Animals as the “Subject of a Life”

Every human and every animal experiences their own “subject of a life.” We each have a unique biography and set of experiences. No matter what sort of body we’re born into, we’ve got one incarnation filled with moments related to companionship, family, and interactions with others. While humans may have vastly different experiences than other animals, we each have but one precious and irreplaceable possession: our own fleeting lives.

Let’s now reflect on why, across every culture, the punishment for murder is invariably severe. The answer is undoubtedly because prematurely ending someone’s life is a bell cannot be unrung. The victim is forever denied the experiences she would have otherwise had, and no remedy for this injustice exists. Certainly, if we agree that murder demands severe punishment because it has unjustly snuffed out a life, we become obliged to consider the implications of animal slaughter in this regard. To cut short an animal’s life terminates that being’s only opportunity to exist. And to do this for culinary pleasure seems especially problematic, especially when delicious alternatives abound.

The subject of a life approach to animal rights can lead people to look at a pig or chicken and decide, “It may not be much of a life, but it’s all they’ve got—and it isn’t ours to take.”

Utilitarianism Applied to Animals

Finally, let’s consider the utilitarian philosophy of Jeremy Bentham. In his 1975 classic, Animal Liberation , Peter Singer applied Bentham’s thinking to animal rights with groundbreaking results.

Utilitarianism is based on the idea that morality is expressed by maximizing total joy and minimizing total suffering. It therefore seeks to evaluate every situation in order to produce the greatest amount of pleasure. For instance, more total happiness is created by giving ten people one sandwich apiece than by handing ten sandwiches to one person.

Utilitarian considerations enable clearer thinking about animal use. Most of us can agree, for instance, that pepperoni is a delicious pizza topping. There is consequently some added joy that comes with being able to order your pizza with pepperoni. But from a utilitarian point of view, it’s unethical to value this added joy without weighing it against how the pig suffered to produce this pepperoni.

You can make a strong case that the animal suffering arising from a particular non-vegan food far surpasses any joy derived from its consumption. This is especially true today, given that vegan meats, dairy products, and eggs are more delicious and readily available than ever. With each passing year, the argument that non-vegan foods provide unique and irreplaceable pleasures becomes increasingly difficult to entertain.

Utilitarianism can inform not just your thinking about food, but also other lifestyle choices like cosmetics, fur, and leather. Nobody pretends it’s possible to calculate joy vs. suffering with the precision of crunching numbers on a spreadsheet. But even so, utilitarianism offers a uniquely helpful framework for evaluating the ethics that pertain to any sort of animal use.

Choosing a Diet that Aligns with Your Values

The concepts of speciesism, subject of a life, and utilitarianism offer ample reason to embrace a vegan lifestyle, or at the very least to eat more plant-based foods. These approaches lead us to what I consider the crux of the matter: are you okay with cutting the throat of a healthy animal who wants to live, just for the sake of eating a certain type of food?

Is slaughtering animals for food a violation of their rights, or is this part of the circle of life? Surely, we each owe it to the animals to give the matter some thought.

Why Go Vegan for Your Health?

No diet can guarantee a long and healthy life, but becoming vegan may improve your odds. That’s largely because a vegan diet eliminates a number of unhealthful foods—including red and cured meats—which are strongly linked to colon cancer .

Vegans also generally eat more vegetables and fruits than non-vegetarians. Studies consistently show that people who eat the most fruits and vegetables tend to enjoy better health . Research also suggests that vegans suffer lower rates of heart disease and diabetes . This reduced risk is partly due to the fact that vegans are statistically leaner and much less prone to obesity than the general population, but this isn’t the whole explanation. Additional benefits probably arise from low saturated fat intake and from the healthful compounds in plant foods.

The Potential Benefits of Ditching Dairy

A surprisingly large number of vegans will tell you that quitting dairy changed their lives. Some people tolerate milk well, and can consume plenty of dairy products without repercussions. But milk products can cause all sorts of chronic health ailments. These range from migraines to acne to digestive problems. And people of Asian or African descent are often lactose intolerant, which makes them prone to gastric distress if they consume dairy products. Many people suffer from these conditions for decades, yet never suspect that dairy products are to blame.

I can personally attest to the health benefits that may accompany going dairy-free. My lifelong severe nasal congestion forever vanished within weeks of eliminating milk products from my diet.

With all this in mind, even people unswayed by environmental and animal rights concerns might consider quitting dairy products. Given the potential rewards, why not go dairy-free for a couple of weeks to see what happens?

Vegan Diets Support High Levels of Fitness

Some people fret that a vegan diet might inhibit athletic performance, but that’s not a valid concern . A well-planned vegan diet can in fact support the highest levels of fitness. Both Rich Roll and Scott Jurek , two of the world’s most accomplished ultra-endurance athletes, are long-time vegans.

But what about sports that require strength and bulk? The bodybuilding community is full of world class vegan athletes . And in 2018, fifteen members of the NFL’s Tennessee Titans switched to a vegan diet .

Moving from “Why Go Vegan?” to “How to Go Vegan?”

Given the degree to which our food choices impact animals, our health, and our environment, this essay could offer only the briefest coverage of the most important issues. But you certainly now know enough to think productively about the topic.

If there’s one point that I hope this essay convincingly made, it’s that the way we eat carries profound consequences. Our food choices matter immensely. I hope I’ve inspired you to dive deeper into whatever aspects of this topic interest you most.

Small Changes Beat No Changes

Many people succumb to all-or-nothing thinking when it comes to contemplating dietary change. For instance, if they decide they aren’t ready to go vegan, they’ll often take no action at all. But even the smallest steps in a plant-based direction can deliver important results, while laying the groundwork for future progress.

So if you’re not ready to commit to major dietary change, how about taking a smaller step? Concepts like Meat Free Mondays , Reducetarian diets , and Vegan Before 6:00 offer something for everyone. If there’s an animal product you presently eat that you don’t really enjoy, why not cut it out today?

Emphasize Exploration

Shifting your diet toward plant-based foods provides all sorts of rewards. If you try new vegan foods at every opportunity, your diet will automatically move in a positive direction.

Here’s my #1 piece of advice: don’t seek to cut out non-vegan foods from your diet. Instead, crowd them out by finding new vegan foods you prefer. The more new foods you try, the more progress you’ll make. As long as you make your transition fundamentally about discovery, switching to a vegan diet requires zero willpower. It’s exciting to know that vegan meats, as well as egg and dairy alternatives, are continually getting tastier , which is something you can’t say for animal-based foods.

I’ve followed a vegan diet for more than thirty years, so I hope you’ll take my word for this: as you incorporate more vegan foods into your diet, the amount of pleasure you derive from eating will grow by leaps and bounds. You’ll enjoy a wider variety of delicious food than ever before, and you’ll probably feel better as well.

Always Take the Easy Route

When transitioning your diet, give yourself every advantage. You don’t have to figure everything out yourself — a little reading pays off big time. My essay on how to go vegan will teach you most of what you need to know in just thirty minutes. After reading it, perhaps read my guide to vegan cooking , discover the easiest vegan foods , or explore the most vegan-friendly cuisines .

Above all, enjoy yourself. Food provides one of life’s great pleasures. As you align your diet to your core values and beliefs, you’ll gain a whole new level of satisfaction from eating.

For further reading, see my regularly-updated list of recommended books. ***

If you found this essay of value, I need your help getting it into more hands. Would you please consider sharing it via email or social media? Thanks! —Erik Marcus

• Compassion in World Farming, Strategic Plan 2018-2022 , p. 6.
• Bernard Rollin was the first academic to rigorously explore the origins of factory farming. His 1995 book, Farm Animal Welfare: School, Bioethical, and Research Issues, expertly covers the development and spread of factory farming methods. A more recent recounting of the origin of factory farming can be found in Philip Lymbery’s Dead Zone: Where the Wild Things Were (2017).
• Jim Kinney, “ Information on suicide prevention arrives with checks for Agri-Mark’s dairy farmers; milk prices expected to keep dropping, ” Feb. 7, 2018. MassLive.com
• M. J. Zuidhof et. al. “ Growth, efficiency, and yield of commercial broilers from 1957, 1978, and 2005, ” Poultry Science, Volume 93, Issue 12, 1 December 2014, Pages 2970–2982.
• Erik Marcus, Meat Market: Animals, Ethics, & Money , Brio Press, 2005. pages 20-21.
• USDA: The Changing Landscape of U.S. Milk Production , and, “ Milk: Production per Cow by Year, US ”
• Quoted on page 58 of my book, Meat Market: Animals, Ethics, & Money . Copyright 2005.
• The ethics of boiling lobsters to death is explored in meticulous detail in David Foster Wallace’s magnificent essay, “ Consider the Lobster ,” which I regard as among the greatest pieces of animal rights writing ever created.

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Vegan diet: nutritional components, implementation, and effects on adults’ health.

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• 1 Institute of Health Sciences, Medical College of Rzeszów University, Rzeszów, Poland
• 2 Faculty of Health Sciences, Department of Physiotherapy, Jagiellonian University Medical College, Kraków, Poland
• 3 Orthopedic and Rehabilitation Department, Medical University of Warsaw, Warsaw, Poland

Vegan diet has emerged as a popular dietary choice for people worldwide in recent times, due to concerns such as health issues, animal rights and welfare, and the sustainability of the environment. The purpose of this literature review was to explain how a vegan diet may affect the health of adults and to point out beneficial components found in it as well as any difficulties associated with its implementation. Evidence supports that a vegan diet can reduce the risk of chronic diseases, such as type 2 diabetes, hypertension, and certain types of cancer. A well-planned vegan diet must include adequate calories and nutrients, as well as the necessary supplements, such as vitamin B12, vitamin D and EPA/DHA. Given the current growing interest in plant-based diets among the general population, it is crucial to understand both the barriers, risks, and benefits of the vegan diet among physicians, policy makers, and the general population.

1. Introduction

1.1. topic overview.

Vegan diet has become a popular diet choice for people around the world, in recent times, due to concerns such as health issues, animal rights and welfare, and sustainability of the environment ( 1 ). A recent nutrition report from Germany stated that the number of vegetarians and vegan shaved doubled from pre-COVID (5%) to post-COVID (10%) ( 2 ). The prevalence of vegans in Europe has been estimated to be between 1 and 10% ( 3 ). Over the years, research has explored the nutritional benefits of a vegan diet and its potential effects on health and well-being. A well-planned vegan diet contains only plant-derived foods, such as fruits, vegetables, legumes, grains, seeds, and nuts ( 4 ). While these natural sources offer a myriad of essential nutrients, special attention must be paid to certain key components that may be more difficult to obtain solely from plant-based sources. To prevent deficiencies and ensure overall health and well-being, particular attention must be paid to nutrients such as protein, iron, calcium, vitamin B12, vitamin D, and omega-3 fatty acids with a very long chain in a vegan diet ( 5 ). As adults cultivate a vegan lifestyle, their dietary choices can substantially affect their health ( 6 ). Many studies have identified that a well-planned vegan diet can provide numerous health benefits. Evidence supports that a vegan diet may reduce the risk of chronic diseases, such as type 2 diabetes, hypertension, and certain types of cancer ( 5 ). Research conducted in Adventists has presented convincing evidence that adequately balanced vegan diets are nutritionally sufficient ( 7 ). On the contrary, inadequate intake of critical nutrients, such as vitamin B12 and iron, can lead to anemia and other health complications if not addressed or attended appropriately ( 8 ). The plant-based diet index has been developed to assess intakes of both plant and animal foods, considering the quality of plant foods: overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), and unhealthful plant-based diet index (uPDI). All indices negatively weigh animal foods, but differently weigh plant foods depending on their nutritional quality ( 9 ). Previous studies have reported that hPDI was associated with a lower risk of cardiovascular disease or type 2 diabetes ( 10 , 11 ).

Central to the interest in the vegan diet lies its foundation in plant-based foods, which are abundant in a diverse array of bioactive components. These constituents contribute to the potential influence of the diet on health, especially in adults ( 12 ). Bioactive components are inherent compounds within plant foods, which extend their impact beyond basic nutrition ( 13 ). Functioning as key regulators, these bioactive components modulate physiological processes and are associated with a spectrum of positive health advantages, such as antioxidant, anti-inflammatory, and anticarcinogenic properties ( 13 ). Flavonoids have positive effects on cardiovascular health and anti-cancer properties. Carotenoids exert protective effects against several types of cancers, in addition to their benefits for vision and skin. Glucosinolates have protective roles against cancer and dementia ( 13 ).

Research has indicated that a well-planned vegan diet can confer improved health benefits while aligning with principles that favor ethical and environmental concerns ( 6 ). However, certain knowledge gaps must be explored. By extensively exploring the nutritional components of a vegan diet and their implications for well-being, individuals, especially adults, can make informed choices about adhering to a vegan lifestyle. This article analyses the essential aspects of a well-planned vegan diet, while concentrating on its nutritional components, health effects in adults, and specific nutrients that require careful consideration to ensure the maintenance of optimal health. Therefore, the purpose of this review of the literature was to explain how a vegan diet may affect the health of adults and to point out the beneficial components found in it, as well as any difficulties associated with its implementation.

2. Materials and methods

The article is of a narrative review nature. The main objective of this study was to review scientific publications in order to establish relationships arising from the adoption of a vegan diet among adults. Attention was focused on the beneficial components present in the vegan diet and their impact on health, the appearance of vitamin deficiencies, and the challenges associated with adhering to this type of diet.

The following source selection criteria were applied: studies related to the adoption of a vegan diet among individuals aged 40–85 years, encompassing randomized clinical trials, observational studies, meta-analyses, systematic reviews, as well as documents containing recommendations and guidelines.

General reviews, case studies, articles not published in the English language, and studies involving pregnant and breastfeeding women and athletes were excluded from the review.

The following databases were utilized: PubMed, Science Direct, Web of Science, Scopus, Google Scholar, CINAHL, Web of Knowledge, Medline, PsycINFO. The search process employed the following words, phrases, and sentences in accordance with the content and purpose of the study: “vegan diet,” “adults,” “bioactive compounds,” “health,” “plant sources,” “carotenoids,” “antioxidants.”

In total, 155 literature sources were collected.

3. An explanation of the vegan diet

It should be noted that the various types of diet that exist are identified and distinguished by the items that are included and excluded ( 12 ). According to Jakše et al., a vegan diet can be described as one excludes any foods derived from animals but is rich in foods from various plant-based dietary groups, such as fruits and vegetables, grains, legumes, nuts, etc. and the vegan diet is the most stringent version of a plant-based diet ( 4 ). Insights collected from previous research indicate that a carefully structured vegan diet can lead to notable health benefits, as the components of food typically contain essential components vital for well-being ( 4 ).

4. Substances/compounds present in vegan diet

4.1. dietary fiber.

Dietary fiber is an integral component of the vegan diet, offering multifaceted contributions to human health. Dietary fiber resists digestion within the gastrointestinal tract ( 12 ), providing a range of physiological benefits that encompasses the modulation of digestion, absorption of nutrients, and impact on gut microbiota ( 14 ). Depending on how well fibers dissolve in water, they can be classified as soluble or insoluble ( 15 ). Soluble fiber, found in foods like fruits, oats, and beans, dissolves in water to create viscous substances. This property contributes to slowing digestion and increasing satiety ( 16 ). On the other hand, insoluble fiber, prevalent in whole grains and vegetables, adds bulk to fecal matter, thereby facilitating regular bowel movements and preventing constipation ( 14 ). The mechanisms through which dietary fiber exerts its health effects are well-established. Soluble fiber forms a gel-like matrix within the digestive tract, delaying stomach emptying and retarding glucose absorption, thus supporting blood glucose regulation ( 17 ). Furthermore, dietary fiber has a positive influence on gut microbiota. The interaction between dietary fiber and gut microbiota involves a fermentation process. Bacterial fermentation of fibers, including resistant starch, some simple sugars, and polysaccharides, leads to the production of short-chain fatty acids (SCFAs) like acetate, propionate, and butyrate. These SCFAs play an essential regulatory role in lipid metabolism, cholesterol and glucose regulation, anti-inflammatory responses, immune functions, and the maintenance of the integrity of the gut barrier ( 18 , 19 ). These SCFAs create an environment conducive to the growth of beneficial bacteria such as Lactobacillus and Bifidobacteria . These bacteria thrive on SCFAs and utilize saccharide metabolism to compete effectively with harmful bacteria for resources ( 18 ). These microbial byproducts, along with other bioactive compounds formed through the fermentation or degradation processes driven by gut microbiota, not only provide vital sustenance for the growth of gut microbes but also exhibit the capacity to influence diverse pathways within the intestines, liver, and pancreas, thereby contributing to the overall enhancement of gut health ( 20 ).

SCFAs offer a broad spectrum of health-enhancing effects, acting as anti-inflammatory agents by regulating cytokine production and immune cell functions. In colon cancer cells, they demonstrate properties that counteract carcinogenesis by influencing acetylation and activating G protein-coupled receptors (GPCRs); they also share associations with microRNAs and Vascular Endothelial Growth Factor (VEGF) ( 19 ). In particular, SCFAs play a vital role in preserving the integrity of the intestinal barrier by coordinating the expression of tight junction proteins. Furthermore, they contribute to alleviating oxidative stress by regulating oxidoreductase activity, promoting nuclear factor erythroid 2-related factor 2 (Nrf2), and reducing reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels ( 19 ). Disruption in the equilibrium of the gut microbiota can result in impairment of the intestinal barrier, thereby increasing susceptibility to particular diseases ( 21 ). Simultaneously, microbial byproducts like short-chain fatty acids and other bioactive constituents, generated through the fermentation or breakdown processes facilitated by gut microbiota, serve as essential nourishment for the proliferation of gut microbes. Furthermore, these compounds have the potential to influence various pathways within the intestines, liver, and pancreas, ultimately contributing to improved intestinal health ( 22 ).

Based on findings from a study exploring the association of dietary type with fecal microbiota and short chain fatty acids in vegans and omnivores, it was observed that individuals following the vegan diet showed a distinctive composition of gut microbiota, characterised by increased amounts of Firmicutes and Bacteroidetes ( 23 ). In the study by Reiss et al., Firmicutes and Bacteroidetes were shown to make up about 95–97.7% of the total gut microbiota in vegans and omnivores, with Firmicutes contributing around 59% and Bacteroidetes contributing 39% to the total gut microbiota in vegan ( 23 ). Compared to omnivorous diets, vegan diets are generally richer in fiber and contain less saturated fat and protein. Long-term vegetable intake has been shown to correlate with gut microbiota diversity, and higher fiber intake increases the prevalence of microorganisms associated with a healthy gut ( 24 ).

Another study investigated the interaction between dietary fiber intake and microbial diversity within diverse diet patterns, including the vegan diet. Although there was no notable variation in microbial abundance between diets, the study found that people following a vegan diet exhibited reduced microbial diversity compared to those consuming a western diet. Subsequent analysis of beta diversity indicated discernible differences in the composition of gut microbiota, regardless of fiber intake levels. Notably, within the vegan group, both high and low fiber intake led to unique microbial compositions compared to the Western Diet. These findings underscore the collaborative impact of diet composition and fiber intake on the diversity of the gut microbiota, highlighting the need to consider both aspects in understanding interactions between diet and gut microbiota ( 25 ). The study emphasizes the importance of considering diet quality, aligning with a research that underscores the role of incorporating whole foods and dietary fiber to foster improved and holistic health results ( 8 ).

Consequently, this mechanism forms a protective barrier against the invasion and proliferation of pathogenic bacteria, contributing to the establishment of a healthier and more balanced gut microbial community ( 5 ). Insoluble fiber, due to its bulk-enhancing effect, accelerates intestinal transit and prevents constipation, functioning through the mechanical stimulation of regular bowel movements and the maintenance of gut motility ( 26 ). The role of dietary fiber in mitigating constipation has been established. A randomized controlled trial that administered a “vege powder” comprising whole grains, broccoli and chicory to constipated participants showed improved symptoms, including increased defecation frequency, softer stool, and reduced strain ( 14 ). Additionally, dietary fiber has demonstrated efficacy in enhancing insulin sensitivity and overall metabolic health. According to Barber et al., an observational study highlighted an association between increased dietary fiber ratio and a significant reduction in HbA1C, when compared to general carbohydrate intake ( 14 ). A double-blind, randomized, placebo-controlled trial suggested the potential for fiber as a complement to lifestyle and/or pharmaceutical interventions for managing type 2 diabetes including improved HbA1c ( 27 ). Dietary fiber offers an array of critical functions within the context of a vegan diet. Its contributions include weight management, lowered cholesterol levels, stabilized blood glucose levels, and improved digestive health ( 4 ). A randomized controlled trial comparing the effectiveness of different plant-based diets for weight loss investigated how various diets influenced weight loss and dietary behaviors, revealing significant insights. Diets did not emphasize caloric restriction. During 6 months, participants adhering to a vegan diet exhibited the most substantial weight loss (−7.5% ± 4.5%), surpassing the other diet groups. This weight loss trend was statistically significant at 2 months ( p < 0.01) and 6 months (p < 0.01). Notably, the vegan group showed significant increases in fiber intake compared to other groups at 2 months (p < 0.01), underscoring the potential impact of dietary fiber, particularly within vegan diets, on weight loss outcomes. These results underscore the importance of incorporating fiber-rich diet choices, such as those of a vegan diet, to promote successful weight management ( 28 ).

Furthermore, in a prospective study investigating the effects of changes in the diet pattern on diabetes risk, the exclusion of individuals with existing diabetes, elevated fasting blood glucose, a history of cancer, coronary heart disease, stroke, and alcohol / cigarettes led to a final analysis of 2,918 participants. Within this group, nonvegetarians demonstrated higher BMI, waist circumference, and fasting blood glucose levels. During a 5.2-year period, 183 participants developed diabetes. In particular, both people who consistently followed high-fiber diets and those who recently switched to such diets exhibited a remarkable 40–60% decrease in risk of diabetes compared to non-vegetarians. This protective effect of embracing a high fiber diet was particularly pronounced among those with healthier metabolic profiles. The robustness of these findings was consistently supported by sensitivity analyses. Taken together, the evidence from this study underscores the potential of adopting a high-fiber diet, whether through ongoing adherence or conversion, to significantly mitigate the risk of diabetes ( 29 ).

This makes a vegan diet particularly advantageous for adults who may be susceptible to various chronic diseases and disorders.

4.2. Bioactive components

Plants contain essential minerals necessary for a well-balanced human diet, along with other primary and secondary metabolites that affect both nutrition and health ( 12 ). Plant foods serve as abundant reservoirs of nutrients such as magnesium, calcium, potassium, minerals, and vitamins, and bioactive elements such as polyphenols, dietary fiber, and carotenoids. For antioxidants, their health benefits have been well established. Antioxidants are compounds in plants that counteract the harmful effects of oxidative stress, protecting cells from free radical damage. They can be obtained from the phenolic components of plants ( 12 ). The role of antioxidants in mitigating damage caused by free radicals has been extensively studied. The consumption of a large number of plant-based foods in the diet reveals this significant benefit ( 30 ). Consuming plant foods rich in antioxidants has been associated with reduced risk against various diseases such as cancer, cardiovascular disease, and type 2 diabetes ( 30 ). A study conducted by Miller et al. (2017) investigated a cohort of 135,335 younger and older adults from 18 different countries. The findings of this study indicated a significant link between a diet rich in fruits, vegetables, and legumes and a decreased susceptibility to cardiovascular-related mortality. The observation of this study implies that the phytochemicals in these plant-based foods could play a role in mitigating diabetes and decreasing susceptibility to cardiovascular diseases. These potential mechanisms include the regulation of α-glucosidase and lipase activities, the postprandial decrease in blood glucose levels, anti-inflammatory effects, enhancement of pancreatic function, and potential synergistic interactions with hypoglycemic medications ( 30 ). Vegan diets play a vital role in counteracting the detrimental effects of free radicals and ROS by harnessing robust antioxidant capacities. Abundant in antioxidants, the vegan diet effectively combats harm related to oxidative stress, promotes cellular health, and reduces susceptibility to chronic diseases ( 31 ). Antioxidants also regulate immune processes, reduce DNA damage, and reduce lipid peroxidation, all of which contribute to better health ( 13 ). By donating electrons, antioxidants disrupt the chain reaction of oxidation, effectively mitigating cellular damage ( 26 ). Within a vegan diet, a variety of diverse antioxidants, including vitamins C and E, polyphenols, and carotenoids, collaborate synergistically to counteract the formation of ROS arising from multiple origins such as metabolic processes, lifestyle activities, and environmental elements. This holistic defensive mechanism offers robust protection against the aforementioned diseases ( 26 ). In addition to scavenging free radicals, research has shown that antioxidants in fruits and vegetables are responsible for the expression of genes through transcription factors, cell signaling modulation, and enzyme activities. These antioxidant properties can be linked a reduction in oxidative stress, improved cell function, and a lower risk of chronic diseases ( 30 ). Carotenoids represent another group of bioactive compounds found in a vegan diet. Fruits and vegetables that are yellow or orange possess this bioactive compound ( 32 ).

Carotenoids are known for their diverse health-promoting characteristics, including anti-cancer, anti-inflammatory, anti-aging and anti-microbial traits ( 12 ). They eliminate free radicals by neutralising them and blocking lipid peroxidation, which is associated with cell damage ( 33 ). In particular, carotenoids serve as precursors to vitamin A, which is a crucial fat-soluble vitamin with various functions in maintaining health and immune function ( 34 ). Vitamin A is known to regulate the differentiation and proliferation of immune cells, thus affecting the immune response ( 33 ). Furthermore, it has been postulated that they can interact with nuclear receptors, such as retinoic acid receptors, influencing gene expression involved in inflammation and immune function. Through conversion to vitamin A, they are recognized for their pivotal role in the health and functionality of photoreceptor cells in the eyes, for good vision ( 33 ). In a study with 74 participants having type 2 diabetes, an 8-week fruit and vegetable (F&V) intervention significantly increased carotenoid levels, including α -carotene, β -cryptoxanthin, lutein, and zeaxanthin ( p < 0.05). These increases, ranging from ~8% to ~25%, were evident in both serum and HDL fractions. The results suggest that elevated F&V intake may enhance HDL’s antioxidant properties through an increase in carotenoid content ( 35 ). Polyphenols are another set of bioactive compounds present in plant foods. They are distinguished by the presence of various phenol groups in their chemical structures. These naturally occurring bioactive compounds are synthesized by plants as secondary metabolites. Polyphenols can be classified into four main classes, namely flavonoids, phenolic acids, lignans, and stilbenes, according to their structural characteristics ( 16 ). Numerous in vitro studies have highlighted the substantial antioxidant capacity of polyphenols, a result of their facilitation of ROS neutralization. This pronounced antioxidant potential, combined with its ability to support nitric oxide (NO) production, contributes to the protection of endothelial function of polyphenols. Furthermore, polyphenols contribute to improving cardiovascular health by inhibiting platelet aggregation, mitigating vascular inflammation, facilitating apoptosis, reducing LDL cholesterol oxidation, and improving lipid profiles ( 16 , 36 ). Investigating the effects of bioactive compounds, a study explored the potential cardiovascular benefits of olive oil polyphenols, yielding significant insights into LDL-related health outcomes. This 3-weeks randomized controlled trial in Men investigated the effects of olive oil polyphenols on health. The intervention led to reduced LDL concentrations, including apolipoprotein B-100 (apo B-100) levels a crucial component of LDL, which has a history of being associated with atherosclerosis and cardiovascular risk, making the reduction in apo B-100 levels a significant finding and total LDL particles, compared to low-polyphenol olive oil ( p = 0.004 and p = 0.013, respectively). Notably, the high-polyphenol olive oil intervention also lowered the number of small LDL particles ( p = 0.029) and increased LDL resistance against oxidation ( p = 0.038), suggesting potential cardiovascular benefits by improving LDL-related health outcomes ( 37 ).

Another study was conducted to compare polyphenol intakes according to different food patterns and food sources in the Adventist Health Study-2 cohort. Among the dietary groups examined, vegans emerged as having the most substantial polyphenol intake. This elevated intake among vegans was statistically significant ( p < 0.05). These observations emphasize the potential of a vegan dietary approach to offer increased polyphenol consumption, underscoring its relevance in the intake of bioactive compounds ( 38 ). Furthermore, exploring the effects of polyphenols, a study investigated the influence of strawberry and cranberry polyphenols (SCP) on parameters such as insulin sensitivity, glucose tolerance, insulin secretion, lipid profile, inflammation, and markers of oxidative stress in individuals with insulin resistance, overweight, or obesity. The trial included participants with similar baseline characteristics. In particular, the SCP group demonstrated a significant 14% increase in insulin sensitivity ( p = 0.05), while the control group showed a nonsignificant decrease of 7% ( p = 0.28). This improvement in insulin sensitivity within the SCP group was statistically significant in contrast to the control group ( p = 0.03). Although the responses to glucose, insulin, and free fatty acids aligned between the groups, the SCP beverages contributed to higher levels of specific phenolic metabolites in plasma. Of particular interest was the discovery of a significant negative correlation between plasma p-coumaric acid concentration and changes in the response to C-peptides during the oral glucose tolerance test (OGTT) ( p = 0.0046, r^2 = 0.34). This observation suggests a potential association between different phenolic metabolites arising from SCP consumption and the improvement of insulin sensitivity ( 39 ). Another study also highlighted the effects of polyphenols on health. The objective was to investigate the effects of polyphenols and omega-3 fatty acids (LCn3) on various health markers. To achieve this, participants were randomly assigned to one of four nutritional isoenergetic interventions for 8 weeks: a control diet low in LCn3s and polyphenols; a diet rich in LCn3s and low in polyphenols; a diet rich in polyphenols and low in LCn3s; or a diet rich in both LCn3s and polyphenols. Throughout the controlled diet interventions, the experimental groups showed significant variations in polyphenol and LCn3 content. The baseline characteristics were consistent among all groups. Fasting levels of lipids, cholesterol, and glucose did not show notable differences. Body weight remained steady throughout the intervention, with slight reductions in the high-LCn3 group. Waist circumference changes were insignificant. Polyphenols appeared to significantly lower fasting triglycerides and cholesterol in larger lipoprotein fractions, while omega-3 fatty acids (LCn3) did not produce significant effects. After meals, lipid and lipoprotein levels improved, mainly due to the impact of polyphenols on triglycerides. Furthermore, markers of oxidative stress, such as 8-isoprostane, decreased significantly in the high-polyphenol groups. Interestingly, the effects of diets naturally rich in polyphenols and/or marine LCn3s on urinary 8-isoprostane were correlated with changes in plasma lipoproteins, particularly in polyphenol-rich groups ( 39 , 40 ).

Polyphenols have the ability to modulate enzyme and anticancer activities and metal chelation, all of which contribute to their intrinsic characteristic of reducing the occurrence of chronic diseases ( 41 ). They prevent cytokines from binding to cancer cells and prevent oxidative stress, thus protecting against cancer ( 42 ). Certain types of polyphenols found in varieties such as green and black tea exhibit the ability to inhibit the growth of harmful bacteria such as Helicobacter pylori, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa ( 20 ).

Another substance, ferulic acid, is a phenolic acid of the polyphenol family, found more commonly in plant-based foods such as cereals, fruits, and vegetables. It has antioxidant qualities that can help prevent many chronic diseases ( 36 ). Anthocyanins have also been found to have great antioxidant properties. They support health by controlling metabolic syndromes and neurological diseases ( 12 ). Anthocyanins exhibit the ability to form complexes with metal ions, reducing the catalytic influence of active metal ions on the generation of free radicals. This interaction contributes to an elevated antioxidant effect. In addition, anthocyanins can form complexes with copper, effectively inhibiting the oxidation of LDL induced by copper or proxy radicals ( 41 ). Vitamin C (ascorbic acid) and vitamin E (tocopherols) represent two potent antioxidants obtained primarily through the consumption of fruits and vegetables ( 12 ). Vitamin C is recognized for its involvement in cellular signaling, programmed cell death (apoptosis), and the maintenance of cell growth. Vitamin C is also a premier water-soluble antioxidant – it also functions to recycle vitamin E (e.g., reduction to active form). Vitamin E, a fat-soluble micronutrient, is involved in DNA protection and has been suggested to play a pivotal role in mitigating the reactivity of redox-active metals, such as copper and iron. In addition, vitamin E contributes to protecting against lipid peroxidation, which exemplifies its multifaceted functions in maintaining cellular health ( 34 ).

5. The health benefits of a vegan diet

5.1. overweight and obesity prevention.

Numerous studies have shown how vegan diets affect body composition, particularly when it comes to losing weight ( 31 ). Vegan diets likely lead to weight loss because they are associated with a reduced calorie intake due to a lower fat content and a higher dietary fiber content. Calorie density is very important for reducing body weight. Consuming foods with lower calories is more advantageous for weight loss than reducing portion sizes ( 30 ). Foods of plant origin have a lower calorie density than foods of animal origin ( 43 ). Data from the Adventist Health Study (AHS) have shown that the body mass index (BMI) increases as the amount of animal foods in the diet increases ( 44 ). Furthermore, results from the European Prospective Investigation into Cancer and Nutrition – Oxford (EPIC-Oxford) study have shown that vegans gain significantly less weight as they age compared to omnivores ( 45 ). The European Prospective Investigation into Cancer and Nutrition-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home and Obesity (EPIC-PANACEA) study, found a positive association between total meat consumption and weight gain, even after adjusting for energy intake: an increase in 250 g/day of meat led to a weight gain of 2 kg after 5 years (95% CI, 1.5–2.7 kg) ( 46 ). In a study that examined a cohort of 49,098 Taiwanese adults, the percentage of participants with a BMI ≥ 27 kg/m2 was significantly lower among those following a vegetarian diet (10.9%) as compared to those following a non-vegetarian diet (15.4%). Furthermore, this study also found that for each year on a vegan diet, the risk of obesity decreased by 7% ( 47 ).

Vegan diets have been shown to have the lowest calorie density and the least amount of cholesterol among various plant-based diets ( 41 ). According to a study conducted by Kahleova et al. overweight participants with a body mass index between 28 and 40 kg/m2 were randomly assigned to follow a low-fat vegan diet in a randomized clinical trial ( 48 ). According to the study findings, the overweight group assigned to a vegan diet experienced a considerable decrease in fat mass and visceral fat compared to the control group. Research has shown that a vegan diet can help adults lose weight by replacing high-calorie items with low-calorie alternatives and maintaining a balance between energy intake and energy expenditure ( 40 ). Based on available evidence, the vegan diet should be considered a viable option for patients who are interested in preventing overweight and obesity or losing weight. Researchers report that a vegan diet is generally associated with a healthy lifestyle that excludes smoking and includes regular physical activity. It is very likely that the health benefits from such nutritional behavior are the result of the combination of these factors, and not only the diet alone. Such a lifestyle provides many benefits and can prevent some chronic lifestyle-associated diseases, including obesity and cardiovascular diseases (CVD).

5.2. Cardiovascular diseases (CVD)

Cardiovascular disease is a major cause of mortality and is currently responsible for a third of all deaths worldwide ( 1 ). CVD is a collection of different conditions that are directly related to the health of the heart. These include arteriosclerosis, arterial stenosis, arterial thrombosis, coronary heart disease and high blood pressure ( 49 ). Plant-based diets reduce CVD risk factors, as confirmed by a meta-analysis and systematic review of prospective cohort studies by Quek et al. in which they show a beneficial effect of plant-based diets in terms of reducing cardiovascular mortality and CVD ( 50 ). However, specifically in the context of a vegan diet, the systematic review by Kaiser et al. evaluated the usefulness of vegan diets in the prevention of cardiovascular disease ( 51 ). The evidence among the Western populations studied weakly suggests an association between vegan diets and the risk of cardiovascular disease. The risk of total CVD, coronary heart disease, acute myocardial infarction, primary stroke, haemorrhagic stroke and ischaemic stroke was assessed. None of the trials found a significantly increased or decreased risk of any cardiovascular complication in people who followed a vegan diet. The authors noted that due to the limited number of high-quality studies, the overall evidence on the role of a vegan diet in the development or prevention of CVD is weak ( 51 ). In this year’s systematic review and meta-analysis of prospective cohort studies, Dybvik et al. observed an 18% reduction in the relative risk of ischaemic heart disease among vegans. No clear association was observed between vegan diets and CVD or stroke. The authors indicated that the number of studies was limited and the associations unclear and imprecise ( 52 ).

Benefits of vegan diets can include reduced inflammation, blood pressure, total cholesterol, serum glucose, improved endothelial function, reduced risk of blood clots, reduction in body weight, etc. ( 53 , 54 ). These beneficial cardiovascular health results can be attributed to a lower intake of dietary cholesterol, saturated fat, trans fatty acids, processed meat, and a higher and more regular intake of fibre, vegetable protein, beta-carotene, vitamin C, vitamin K, folic acid and magnesium and potassium ( 53 ). The study by Pickering et al. highlights the importance of potassium and magnesium for the health of the cardiovascular system ( 55 ). The main role of potassium in the prevention of cardiovascular disease is due to its influence on maintaining electrolyte balance, reducing blood pressure, and the risk of stroke through its beneficial effects on endothelial function and vascular homeostasis, while magnesium is involved in the regulation of blood pressure and metabolism. It is worth noting that the balance between potassium and sodium is of crucial importance for the health of the cardiovascular system ( 56 ).

In particular, the soluble fiber fraction, through its effects on lowering total cholesterol and low-density lipoprotein (LDL) levels, better glycaemic control, weight loss, and reduced inflammation, provides a number of health benefits in the context of CVD risk reduction ( 57 ). According to Pereira et al. an increase in soluble fiber intake of 10 g per day can reduce the risk of a coronary event by 14% and the risk of coronary death by 27% ( 58 ). Furthermore, the above fiber fraction may have an effect on the production of short-chain fatty acids (SCFAs) in the colon, which in turn may potentially have an effect on cholesterol synthesis ( 59 ). Nevertheless, it is worth noting that in the systematic review and meta-analysis by Wang et al. vegetarian diets were effective in lowering blood levels of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol to a greater extent than control diets; however, it is unclear whether vegan diets have a similar effect ( 60 ). A vegan diet seems to exhibit greater efficacy in reducing overall and LDL cholesterol when compared to omnivorous control diets; nevertheless, its impact on HDL cholesterol and triglyceride levels remains inconclusive ( 61 ).

Vegan diets are also rich in polyphenols, which is relevant in relation to cardiovascular disease. The antioxidant capacity of polyphenolic compounds is known from in vitro studies, mainly through their role in the capture and neutralization of free oxygen and nitrogen species and protection against oxidative stress. This antioxidant capacity, possibly together with their ability to modulate nitric oxide (NO) production, enables polyphenolic compounds to contribute to the maintenance of vascular homeostasis. Through their role in inhibiting platelet aggregation, reducing vascular inflammation, modulating apoptotic processes, reducing LDL oxidation, and improving the lipid profile, polyphenols can also contribute to cardiovascular health ( 62 ).

The gut microbiome is another emerging pathway through which a healthy plant-based diet may influence the risk of CVD ( 63 ). Microorganisms in the gut metabolize a variety of dietary substrates, which can have an impact on cardiovascular health ( 64 ). The trimethylamine N-oxide (TMAO) pathway is an example. Choline and L-carnitine, compounds derived mainly from animal-based foods such as red meat, poultry, and fish, are broken down by microbes in the gut to produce trimethylamine (TMA), which is further broken down in the liver to form TMAO. Associated with an increased risk of cardiovascular events, TMAO is believed to affect heart health through cholesterol and sterol metabolism, inflammation, thrombotic, and atherosclerotic pathways ( 65 ). As a recent study did not find an association between TMAO and dietary factors, it is possible that the association of animal foods with heart disease risk through the TMAO pathway is modified by eating foods rich in TMAO precursors and by gut microbial composition ( 66 ). Certain phytochemicals (e.g., resveratrol) have been found to potentially inhibit TMAO production in animal model studies ( 67 ). Plant-based diets also differ from animal-based diets in several other microbiota-dependent metabolic pathways, including increased metabolism of dietary fiber and polyphenols, and decreased metabolism of bile acids and amino acids, which may mediate links to cardiovascular disease. To elucidate the likely complex pathways by which diet interacts with the intestinal microbial environment to influence cardiovascular health, larger studies with longer follow-up and repeated assessment of diet and microbiome are needed.

There are also limitations and risks associated with following a vegan diet for cardiovascular health, especially if the diet is poorly balanced, as vegans may have lower amounts of dietary nutrients such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), selenium, zinc, iodine, iron, calcium and vitamin B12, vitamin D, compared to non-vegans, which can lead to adverse cardiovascular effects ( 68 , 69 ). Van Winckel et al. stress that it is important to understand that both an unhealthy diet and a vegan diet can induce chronic inflammation, if the vegan diet contains insufficient amounts of nutrients and omega-3 fatty acids ( 70 ). One of the many issues in the context of vitamin B12 deficiency in a vegan diet is the risk of leading to hyperhomocysteinemia. As a result of reduced vascular elasticity and altered homeostasis, elevated levels of homocysteine induce vascular endothelial impairment. This is an important risk factor for CVD ( 44 ). It is also worth mentioning the problem of consuming large amounts of processed plant products in a vegan diet, meat substitutes and dairy substitutes, which can be high in sugars, salt, and trans fatty acids ( 71 , 72 ).

Most short-term studies on vegan diets do not provide accurate data on long-term effects on cardiovascular health, based mainly on changes in biomarkers. Following a vegan diet also brings about a number of health benefits in terms of cardiovascular disease, but is also associated with the risk of nutrient deficiencies. It seems that a well-balanced vegan diet, rich in high-quality plant-based foods such as whole grains, fruits, vegetables and nuts, based on unprocessed products, together with supplementation (for example, an algae-based DHA supplement in addition to regular consumption of sources of ALA and vitamin B12, vitamin D) may be considered a suitable route to the prevention of cardiovascular disease, but more research on this issue is needed ( 49 , 62 ). Although it requires more research and a personalized diet approach, a vegan diet may not only benefit heart health, but may also have the potential to regulate blood glucose levels and manage diabetes mellitus.

5.3. Diabetes mellitus

A chronic metabolic disorder called diabetes mellitus is characterised by persistently high blood glucose levels, insulin resistance, and insufficient amounts of insulin compared to physiological requirements. Due to the decreased sensitivity of the body to insulin hormone, which controls blood glucose levels, and the pancreas’ insufficient ability to produce enough insulin to compensate for this resistance, this syndrome develops ( 73 ).

The global diabetes prevalence in 20–79 year olds in 2021 was estimated to be 10.5% (536.6 million people), rising to 12.2% (783.2 million) in 2045. Just over half a billion people are living with diabetes worldwide which means that over 10.5% of the world’s adult population now have this condition ( 74 , 75 ).

Because a healthful, well-planned vegan diet may be inclusive of entirely whole plant foods such as fruits, vegetables, legumes, whole grains, nuts, and seeds, which are excellent sources of dietary fiber, it naturally contains a lot of fiber ( 1 ). Soluble dietary fiber can improve glycaemic control by delaying the process by which food leaves the stomach, resulting in slower glucose uptake and absorption ( 76 ). It is well established that a vegan diet can tackle important pathophysiological processes related to beta cell dysfunction and insulin resistance. A 16-week randomized controlled experiment with 75 overweight adults, half of whom followed a vegan diet, and the other half a control diet, illustrates this. The vegan group demonstrated a notable improvement in beta cell function and fasting insulin sensitivity compared to the control group. These two elements are recognized to be the main pathophysiological mechanisms driving type 2 diabetes ( 77 ). Another study has shown that fiber helps delay the absorption of glucose in the gastrointestinal tract, which causes blood glucose levels to gradually rise. This result may reduce the likelihood of insulin resistance and hyperglycemia ( 78 ). A study by Chester et al. showed that a low-fat vegan diet resulted in improved glycaemic control and decreased medication consumption in those with type 2 diabetes over the age of 50 years ( 79 ). According to the study, the weight loss effect of the vegan diet may account for a sizable amount of its effects on hemoglobin A1C levels, a measure of blood glucose control over time. A low-fat vegan diet was found to significantly improve glycaemic control in a 22-week randomized clinical trial ( 79 ), which included people with type 2 diabetes. In particular, the study found that the A1C readings in the vegan group dropped noticeably more than those of the other diet group. In a 12-week randomized clinical trial by Lee et al., participants diagnosed with type 2 diabetes were randomly assigned to follow a vegan diet or a conventional diet. Both diets led to lower HbA1c levels, but glycaemic control was better with the vegan diet (0.3–0.6% greater reduction) than with the conventional diet ( 80 ).

5.4. Cognitive function

Quercetin, which is only found in plant foods, may be responsible for the effects of a vegan diet on the reduction of anxiety and/or depressive symptoms ( 81 ). Quercetin can act as a natural antidepressant by inhibiting the activity of monoamine oxidase (MAO), an enzyme that breaks down mood-regulating neurotransmitters such as serotonin, dopamine, and norepinephrine ( 82 ), resulting in higher levels of these neurotransmitters in the brain ( 83 ). This impact might reduce the signs and symptoms of anxiety and despair.

Nutrition plays an increasingly important role in maintaining optimal brain function as people age ( 84 ). Studies have shown a protective effect of a vegan diet against Alzheimer’s ( 84 ). Alzheimer’s disease is a neurological disease that typically develops with increasing age and is known to be the leading cause of dementia worldwide ( 84 ). It is defined by a steady deterioration in cognitive abilities, including memory, reasoning, and behavior. The effects of diet and lifestyle choices, including a vegan diet, on Alzheimer’s disease have received much attention from researchers ( 85 ).

Part of the protective mechanisms of a vegan diet could be attributed to its beneficial effect on the reduction of inflammatory markers in dementia and Alzheimer’s disease. Meat-based dietary patterns appear to be positively correlated with biomarkers of low-grade inflammation, whereas vegetable- and fruit-based diets are inversely correlated ( 86 ). Studies providing data on biomarkers of inflammation in vegans, however, are few and inconsistent. Menzel et al. found no significant differences in any of the seven inflammatory biomarkers measured. Participants who followed a vegan diet for more than 4.8 years were more likely to have lower hsCRP levels compared to those who followed a vegan diet for less than 4.8 years ( 87 ). This may suggest that diet length may be an important factor in reducing systemic inflammation. Šebeková et al. also found that plasma CRP levels were not significantly different between vegans and omnivores ( 88 ). In the other hand, Franco de Moreaes et al. identified lower values of inflammatory markers, CRP and TNF-α/IL-10 ratio in strict vegetarians compared to vegetarians and omnivores ( 89 ). Lastly, a recent meta-analysis showed that vegans have lower CRP levels than omnivores ( 90 ).

With the popularity of veganism rising rapidly, there is an increased need for scientific study to determine how a vegan diet affects human health, particularly in relation to cognitive functioning. A low-risk lifestyle adjustment that can help maintain cognitive function and prevent cognitive ageing is to switch to a vegan diet ( 62 ). Further research is needed to prove that a vegan diet can help prevent or counteract inflammation and subsequently help reduce the risk of Alzheimer’s disease.

5.5. Bone wellness

Numerous health problems have been associated with adulthood and ageing, and the severity of these problems depends on various circumstances. A study by Rodrigues et al. found that ageing is related to a loss of bone mass, increasing the incidence of fractures with age ( 91 ). Osteoporosis is a degenerative skeletal condition that can increase the susceptibility of a person to fractures, especially in the hip, spine, and wrist ( 92 ). Key characteristics of osteoporosis include low bone mass and decreased bone mineral density. The health of an adult is greatly influenced by its diet, which is one of the key determinants. A vegan diet has some consequences, according to several studies conducted in the context of food. Bone health is one example. Bone health problems, which often develop with age, are substantially more common in women than in men ( 93 ). In general, high bone mineral density is preferred since it has a negative correlation with the risk of fragility fractures, especially in female adults. In other words, the lower the risk of fractures caused by decreased bone strength, the higher the concentration of bone mineral ( 94 ). Adopting a vegan diet can raise concerns about inadequate nutrient intake, which can eventually lead to lower bone mineral density (BMD) ( 95 ). Certain nutrients, such as vitamin B12, vitamin D, calcium, and omega-3 fatty acids, may be insufficient in a vegan diet. This is so because, as cited by Richter et al. and Menzel et al., these nutrients are commonly present in animal products ( 96 , 97 ). Vegans showed lower bone mineral density than omnivores in a variety of bone locations, including the hip, femoral neck, and lumbar spine, according to a cross-sectional study conducted by Menzel et al. ( 97 ), which included 36 vegans and 36 omnivores, as well as adults. Furthermore, compared to omnivores, vegans exhibited lower levels of calcium, vitamin D, and vitamin K. However, the bone turnover markers of the two groups did not show appreciable variations. The study findings indicated that vegans should consume enough calcium, vitamin D, and vitamin K to maintain strong bones because they may be more susceptible to osteoporosis and bone fractures. The study also emphasized how crucial nutrient balance is for vegan diets because vegans who consume an unbalanced diet run the risk of depleting many nutrients. Vitamin D, which is often obtained by exposure to sunlight but can also be found in foods such as fatty fish, egg yolks, and the liver, is crucial for the health of bones ( 98 ). The relevance of nutritional practices as a modifiable factor that affects bone mineral density has been acknowledged ( 99 ).

5.6. Muscle integrity

Sarcopenia and frailty syndrome are debilitating conditions primarily associated with aging-related changes in body composition, characterized by low muscle mass and strength. These conditions ultimately lead to an increased risk of adverse health outcomes such as disability, hospitalization, or death ( 6 , 100 ). It is estimated that sarcopenia affects 30% of individuals over 60 years old and 50% of those over 80 years old. Data analysis from 62 countries worldwide indicates a prevalence of frailty syndrome ranging from 12 to 24% of the population ( 101 ). This, in the face of an ever-increasing number of elderly people, is becoming a serious public health problem ( 77 , 78 ). A well-planned diet is essential for older people. Although the evidence base for the role of dietary protein in maintaining good muscle health in older age is strong, the importance of protein sources is an ongoing subject of research ( 101 – 104 ). With the increasing number of people adopting flexitarian, vegetarian, and vegan diets, scientists are highlighting the need to pay attention to the dietary habits of older people to prevent sarcopenia and frailty syndrome. The results of the study conducted by Sotos-Prieto et al. indicate that a healthful plant-based diet was associated with lower risk of frailty whereas an unhealthful plant-based diet was associated with higher risk ( 105 ). Adequate consumption of high-quality dietary protein combined with regular physical activity is crucial to the prevention of the aforementioned conditions among older people ( 106 ). Furthermore, increasing portion sizes could be helpful in improving the intake of protein and essential amino acids (EAAs) to address the challenge of the lower anabolic properties of plant-based foods and proteins. Essential amino acids are essential components found in dietary protein that play a crucial role in maintaining muscle growth and strength throughout an individual’s lifetime. Attention should be paid to the intake of branched chain amino acids (BCAAs), especially leucine, isoleucine, and valine ( 107 ). Ingestion of dietary protein induces hyperaminoacidemia, promoting muscle protein synthesis and inhibiting muscle protein breakdown through various pathways ( 108 ). However, scientific opinions on the use of a vegan diet among older individuals and its impact on the development of sarcopenia are highly divided. According to studies by Hengeveld et al. and Tieland et al., the lower quality of protein present in many vegan meals can be problematic, especially considering that a significant number of adults struggle to meet the recommended increase in dietary protein intake ( 109 , 110 ). According to Domić et al., older Spanish adults who consumed more animal protein than vegetable protein had a lower incidence of frailty. Additionally, researchers point out that several observational studies have shown a favorable correlation between animal-based protein and muscle mass and strength, indicating that a vegan diet might have negative effects on muscle mass and strength ( 6 ). The study conducted by Maroto-Rodriguez et al. provides intriguing results and a fresh perspective on the dietary habits of seniors. According to the researchers, diets with a high consumption of plant-derived foods and a lower consumption of animal-derived foods could potentially reduce the risk of frailty in elderly individuals. The study attributes positive health outcomes to the adoption of a plant-based diet, characterized by a significant intake of plant products and a lower intake of animal products. Unlike other vegetarian diets, a plant-based diet places emphasis on the quality of plant-based items. It associates the favorable impact of healthy plant-derived foods such as vegetables, fruits, whole grains, and nuts with improved health among individuals over 65, in contrast to unhealthy plant-derived products like refined grains, sugary beverages, and animal-based foods ( 111 ). The authors of the study suggest that the protective effect of a plant-based diet against frailty could be linked to the provision of essential nutrients. They highlight the antioxidant effects of vitamins C and E, carotenoids, and selenium derived from fruits and vegetables. These elements may protect against sarcopenia by reducing the exposure of muscle fibers to oxidative stress. However, biomarkers of selenium and zinc were lower in vegans, confirming that a sufficient supply of these trace elements is more difficult to achieve when following a plant-based diet ( 112 ). Additionally, the inclusion of legume and nuts protein might help prevent sarcopenia ( 111 , 113 ). The authors also point out the potential anti-inflammatory effects of fruits, olive oil, unsaturated fatty acids, nuts, or coffee, which may help mitigate the low-grade chronic inflammation associated with frailty ( 111 , 114 ). Similar results are presented by a Chinese study conducted among nearly 4,000 participants ( 115 ).

Researchers have shown that a vegan diet is linked to a reduced risk of frailty in men and older adults who lead a healthy lifestyle. More research is required to establish a vegan diet as a recommended dietary approach to prevent and minimize frailty among older adults. Furthermore, it should be considered to incorporate dietary interventions along with lifestyle changes to promote successful ageing, a factor that could also be significant for women ( 116 ).

Considering the substantial increase in the elderly population worldwide and the significance of the issue, future studies are needed to develop an optimal approach to nutrition and/or supplementation with isolated protein preparations for individuals who, for various reasons, choose to adhere to a vegan diet ( 117 ).

6. Nutritional factors to consider in a vegan diet

Some nutrients need to be taken special into account when following a vegan diet. According to a position document of the Academy of Nutrition and Dietetics (AND), a well-planned vegan diet is nutritious and can have health benefits for the prevention and treatment of various diseases. It also highlights the fact that a vegan diet should be carefully planned to ensure optimal nutritional intake. The article also highlights the particular nutrients in vegan diets that must be taken into account, such as protein, vitamin B12, vitamin D, calcium, iron, and omega-3 fatty acids ( 1 , 118 ).

6.1. Protein

Numerous research efforts have aimed to evaluate the capacity of a vegan diet regimen to meet the appropriate protein requirements. A significant proportion of these studies contend that mean protein intake, which represents approximately 13–14% of daily caloric intake, aligns favorably with the guidelines established by the American diet recommendations ( 119 ). According to a study conducted by Alles et al., 27% of individuals following a vegan diet do not reach a minimum protein intake of 10%, thus initiating enquiries into the sufficiency of protein provisioning within the vegan diet ( 3 ). Conversely, despite a lower average protein intake in vegan diet, all studies reported in the article of Neufingerl et al. protein intake within the level of the adequate macronutrient distribution range (ie 10% E). None of the 64 studies reported protein intake below the acceptable macronutrient distribution range (AMDR) for any dietary pattern ( 53 ). In Bakaloudi et al ’s review of 12,096 vegans, macronutrient intakes were largely adequate in vegans, with the exception of protein, where intakes were lower, slightly below the RNI ( 68 ). However, it should be noted that expert opinion is divided on the protein content of plant-based diets.

Therefore, it is essential for vegans to ensure that they get an adequate amount of proteins in their diet. Protein quality is influenced by the effectiveness of digestion and the presence of crucial amino acids. Another recommendation is to eat a variety of foods as amino acid limitation is not as serious ( 118 ). In particular, certain vegetable proteins, such as soy, exhibit enhanced digestibility, distinguishing them from the typical digestibility observed in many other plant-based foods. This concept is in alignment with the principles of the Digestible Indispensable Amino Acid Score (DIAAS), a widely used measure to assess protein quality ( 3 ). As Mariotti and Gardner highlighted, the distribution of amino acids in plant-based foods often displays a less optimal profile compared to animal-derived foods. However, it should be noted that even when adhering to a vegan diet characterised by limited diversity, achieving a considerable intake of total protein remains attainable. This can be accomplished by consuming significant amounts of plant protein foods, such as soybeans, tofu, legumes, nuts, seeds ( 120 ).

In the context of a vegan diet, the fulfilment of protein requirements is ensured through the complementary consumption of legumes and cereals, allowing individuals to obtain a comprehensive array of essential amino acids that are of paramount importance for human nutrition ( 14 ). This is especially noteworthy when considering that the Recommended Dietary Allowance (RDA) for protein intake is commonly set at 0.8 g/kg body weight ( 120 ). Advancements in modern food technology have played a crucial role in producing plant-based food products that mimic the attributes of animal-derived options. In particular, the use of soy and its derivatives has emerged as a significant strategy, allowing the achievement of satisfactory protein intake that could otherwise be difficult to achieve ( 15 ). Currently, vegans commonly include substantial amounts of legumes in their dietary patterns, a protein source that has gained attention as a potential preventive factor against ailments such as stomach, prostate, and colon cancer. Furthermore, the consumption of legumes demonstrates potential cardioprotective effects, evident through the reduction in serum lipids and lipoproteins circulating, including total cholesterol, low-density lipoprotein (LDL) and triglycerides ( 5 ).

6.2. Vitamin B12

Deficiencies in specific vitamins, particularly vitamin B12is significant concerns in the context of a vegan diet. Vitamin B12, a water-soluble nutrient found primarily in animal-derived foods, plays a vital role in hematopoiesis and nervous system function ( 5 , 14 ). However, due to the absence of animal products, getting sufficient vitamin B12 is a challenge for vegans, leading to potentially severe deficiencies. These deficiencies can be the result of impaired absorption or inadequate intake of this essential nutrient, contributing to conditions such as megaloblastic anemia and degenerative disorders ( 5 , 121 ). In particular, neurological symptoms of vitamin B12 deficiency include numbness and tingling of the hands and feet, decreased sensation, difficulty walking, loss of control of the bowel and bladder, memory loss, dementia, depression, general weakness, and even psychosis. Elevated rates of vitamin B12 deficiency, up to 80%, are observed in populations in Hong Kong and India, particularly among people following a vegan diet with limited inclusion of fortified foods or supplementation ( 5 ). As an exclusive animal-derived nutrient, vitamin B12 is absent in vegan diets, necessitating supplementation or fortified plant-based alternatives such as plant milk, cereals, and nutritional yeast ( 14 , 122 ). Although the established daily recommended dietary allowance for adults in the United States is 2.4 microgrammes of vitamin B12, research suggests that due to variations in the absorption and utilization of vitamin B12 from plant sources, vegans might require higher doses of this vitamin ( 123 ). Therefore, regular monitoring of vitamin B12 levels and adaptive supplementation strategies become imperative to maintain optimal health ( 4 ).

6.3. Vitamin D

Vitamin D, classified as a fat-soluble micronutrient, plays a central role in promoting calcium absorption and maintaining optimal bone health ( 124 ). Its synthesis takes place on the human skin when exposed to sunlight. However, various factors, such as geographic location and time of year, can influence the skin’s ability to produce sufficient vitamin D ( 4 , 5 ). According to research conducted by Melina et al., certain individuals following a vegan diet have been observed to experience a low vitamin D intake and exhibit lower serum 25-hydroxyvitamin D levels, especially during winter or in regions with higher latitudes ( 118 ). Furthermore, a study by Allès et al. indicated that vegans tend to consume less vitamin D relative to recommended dietary guidelines ( 3 ). The recommended daily intake of vitamin D varies, ranging from 600 IU/day to 800 IU/day ( 124 ) or approximately 5 μg to 15 μg ( 52 ). In particular, Menzel et al. underscore the critical nature of this nutrient, as its deficiency could lead to decreased bone mineral density, increased bone turnover, and an increased risk of premature bone ageing, thus increasing the susceptibility to fractures. This concern is particularly relevant for vegans, who, due to their exclusion of animal-derived foods, face an increased risk of inadequate vitamin D supply, which could lead to adverse effects on bone health ( 94 ). Sources of vitamin D include fortified breakfast cereals and non-dairy milk substitutes such as oat, almond and rice beverages. When exposure to the sun and fortified food intake are insufficient to meet dietary requirements, vitamin D supplementation is recommended for individuals of all ages ( 5 ).

6.4. Omega 3 fatty acids

Omega-3 fatty acids, with a particular focus on alpha-linolenic acid (ALA), play an important role in preventing atherosclerosis and improving lipid profiles through the reduction of inflammation and the mitigation of oxidative stress. ALA, which is an essential fatty acid, acts as a precursor for the synthesis of EPA and DHA ( 125 ), but only a small portion is converted to longer-chain fatty acids. Current research indicates that n-3 conversion from short chain to long chain in humans is very limited; ALA converts to EPA at a rate of 5–15%, and < 1% of ALA reliably converts to DHA. Individuals who follow a vegan diet and include no marine foods in their diet will consume ALA because of its wide distribution in plant-sourced foods ( 126 ). However, literature suggests there is individual variation in conversion rate of fatty acids, influenced by genetics and dietary habits, including the presence of other fatty acids in the diet. Vegan may be more efficient at n-3 conversion, but this has not been confirmed ( 127 ).

According to Menzel et al., the main sources of EPA and DHA, include oily fish, dairy and meat, therefore intake of EPA and DHA among vegans is lower compared to omnivores, due to the omission of these foods from their diet. Their study revealed reduced plasma levels of n-3 fatty acids in vegans ( 118 ). ALA sources, such as vegetable oils, cereals, nuts such as walnuts and chia seeds, as well as plant-derived oils such as rapeseed, linseed, canola, and hemp should be included in the well-balanced vegan diet ( 125 , 128 ). Optimizing the intake of omega-3 fatty acids is crucial for those following a vegan diet ( 7 ) as the Adequate Intake (AI) guidelines for n-3 fatty acids suggest a daily intake of 1.1 grams of alpha-linolenic acid for women and 1.6 grams for men ( 128 ). An abundance of foods fortified with EPA and/or DHA from either marine or algal sources are now available; called functional foods, examples include soy milks and juices, cooking oils, spreads, snack foods ( 126 ).

6.5. Calcium

Vegans generally demonstrate lower calcium intake compared to individuals who follow alternative diet patterns such as lacto-ovo-vegetarian diets ( 52 , 118 ). However, though various plant-based sources offer substantial calcium content, its absorption is negatively influenced by compounds such as oxalates, phytates, and fiber present in vegetables ( 5 ). To improve calcium intake, there are a number of interventions that can be implemented. These include promoting the consumption of foods naturally high in calcium, using food processing techniques that could improve calcium content or bioavailability, staple food fortification, and biofortification to produce higher calcium-containing crops ( 129 ). Noteworthy calcium-rich plant foods include green leafy vegetables, tofu, tahini, as well as fortified options such as cereals, soy, rice, and nut and fruit beverages. Optimal absorption is observed in low-oxalate vegetables, such as broccoli and kale ( 5 ). The WHO recommended dietary allowance for adults ranges from 1,000 to 1,200 mg ( 130 ), and meeting this requirement is feasible for vegans by consuming a variety of plant-based foods rich in calcium.

In a comparative study involving various dietary groups, including meat eaters, fish eaters, vegetarians, and vegans, a noticeable increase in fracture rates was observed among vegan participants. This trend appeared to be associated with a significantly lower average calcium intake within the vegan group ( 128 ). The study by Menzel et al. offers information on the impact of transitioning from an omnivorous diet to a vegan diet, revealing a reduction in calcium excretion indicative of dietary changes. The study effectively employed 24-h urine samples to accurately assess mineral statuses, unveiling a decrease in calcium excretion among vegans compared to omnivores. This variation in excretion is probably attributed to differences in dietary calcium intake, which is reflected in urinary calcium concentrations ( 94 ).

Among vegans, decreased plasma zinc levels can contribute to iron deficiency anemia ( 5 ). Poor zinc status is most commonly linked to innate immunity and reduced resistance to infections. Dimitra et al. conducted a systematic review that revealed that vegans have the lowest zinc intake compared to groups following various diet habits ( 52 ). Furthermore, a study carried out by Allès et al. showcased notable insufficiency of zinc among vegans ( 3 ). Zinc serves as a facilitator in iron metabolism and is less readily absorbed from plant-derived sources compared to animal products, which typically contribute about half of the zinc intake. Plant-based sources rich in zinc include wholemeal bread, peas, corn, nuts, carrots, whole grains, wheat germs, soybeans, cabbage, radish, watercress, and legumes ( 5 , 118 ). Vegans are advised to consume these foods in sufficient amounts to prevent zinc deficiency. Supplementation and the inclusion of fortified breakfast cereals and foods could be crucial for meeting the nutritional needs of individuals following a vegan diet ( 124 ). The WHO has established a classification for zinc bioavailability based on the phytic acid: zinc ratio. Ratios below 5 are designated as indicating “high” zinc availability, resulting in 50% absorption (High Bioavailability: Females: 3.0 mg, Males: 4.2 mg). Ratios spanning from 5 to 15 signify “moderate” bioavailability, yielding 30% absorption (Moderate Bioavailability: Females: 4.9 mg, Males: 7.0 mg). Ratios surpassing 15 indicate “low” zinc availability, leading to 15% absorption (Low Bioavailability: Females: 9.8 mg, Males: 14.0 mg). These categories align with recommended zinc intake levels for different gender groups, providing tailored guidance for optimal nutritional adequacy ( 52 , 131 ). Vegan dietary patterns are categorized as possessing a moderate degree of zinc availability, given that their predominant reliance is not on unrefined, unfermented, or ungerminated cereal grains, or high-extraction-rate flours ( 131 ).

Anemia resulting from iron deficiency is more prevalent among vegans than among omnivores ( 124 ). Despite vegans having the potential to achieve a daily iron intake similar to non-vegans, their blood iron and ferritin levels tend to be lower, partly due to the less effective absorption of non-haem iron found in plant-derived foods compared to haem iron from animal sources. This is supported by another study that found higher iron intake among vegans compared to other diets, especially in German vegan women, although the absorption levels did not correspond proportionally to the increased intake ( 5 , 48 ). Iron sources include legumes, beans, whole grains, whole cereals, dark-green leafy vegetables, fruits, seeds, and nuts ( 5 ). Enhanced absorption of non-haem iron is facilitated by ascorbic acid, minor alcohol intake, retinol, and carotenes ( 5 , 132 ). However, factors such as phytates, tannins/polyphenols, and soy protein inhibit absorption ( 133 ). Marrone et al. emphasized that menopausal women among vegans are particularly prone to iron deficiencies. The recommended dietary allowance of iron is established at 8 mg per day for men and 18 mg per day for women ( 130 ). There is an iron RDA specific for vegetarians/vegans in the U.S. due to lack of dietary haem iron: 32 milligrams per day for women and 14 milligrams per day for men ( 119 ). To combat iron deficiency, fortified foods such as salt, wheat flour, and rice can be incorporated into the diet ( 14 ).

Haem iron, which is mainly found in products of animal origin, is not available in a vegan diet. Therefore, people on a vegan diet are not at risk of an excess of this form of iron. Haem iron is a type of iron that is found in haem-containing proteins, such as haemoglobin in the red blood cells and myoglobin in the muscles. It is important to the body because it is necessary for the transport of oxygen from the lungs to tissues and for the storage and transport of oxygen in muscles ( 134 ). However, certain types of damage can occur if there is an excess of haem iron or if it is processed incorrectly. One of the main concerns regarding the harmful effects of haem iron is its role in oxidative stress. This is due to its ability to catalyse the formation of reactive oxygen species. Reactive molecules can cause damage to cells, proteins, lipids and nucleic acid (DNA), which can contribute to inflammatory processes ( 135 ).

Excess haem iron has been positively associated with non-communicable diseases, including colorectal cancer, type 2 diabetes and cardiovascular mortality ( 136 , 137 ). In a meta-analysis of prospective cohort studies by Hunnicutt et al. haem iron intake was positively associated with the incidence of coronary heart disease ( 138 ). In a prospective cohort study among 539 older Australian men aged 75 years and older, it was shown that higher haem iron intake was independently associated with an increased risk of adverse cardiovascular events, mortality from any cause, congestive heart failure and coronary revascularisation over 5 years ( 139 ). The maintenance of the right balance of iron in the body is essential for the maintenance of good health. It is therefore important that not only those who follow a plant-based diet, but also those who eat meat, monitor their iron levels on a regular basis and adjust their diet to include adequate amounts of iron ( 136 ).

7. Guidelines for adopting a vegan diet

Most guidelines on vegetarian and vegan diets have provided neutral advice on supplementing certain nutrients with plant sources. Guidelines such as those from the United Kingdom, Australia, Belgium, Lebanon, Malaysia and Malta indicate that all nutrients can be obtained from a vegetarian diet, including a vegan diet, by combining a variety of foods and consuming an appropriate amount of calories ( 140 ).

For adults aged 18 to 60 years, it is recommended to maintain a total energy intake ranging from 23 to 27 kcal/kg, while those over 60 years should target a range of 19 to 22 kcal/kg. To ensure a balanced carbohydrate and fiber intake, individuals should consume a minimum of 400 g (equivalent to five portions) of fruits and vegetables daily, excluding starchy root and vegetables. Dietary fat intake should be limited to less than 30% of total energy intake, with saturated fats kept below 10% and trans-fats below 1%. It is recommended to substitute saturated and trans fats with unsaturated fats. Protein intake should contribute to approximately 15% of total energy intake. Additionally, it is advised to limit free sugar intake to around 5% of energy and restrict salt intake to 1,500 mg/day when adhering to a vegan diet. To ensure adequate intake of vitamins B12 and D throughout the year can be achieved through vitamin-fortified meals or supplements, and EPA/DHA supplementation (alternate source of EPA/DHA algal oil) is also recommended ( 4 , 60 ).

People following a strict vegan diet can meet nutrient requirements as long as energy needs are met and an appropriate variety of plant foods are eaten throughout the day ( 140 ), and include fortified foods and/or supplements to get adequate amounts of vitamin D and vitamin B12 ( 4 , 60 ).

8. Obstacles to adopting a vegan diet and lifestyle

Individuals adopting a vegan diet can encounter a variety of difficulties. Many people fail to maintain a vegan diet in the long term and give up ( 133 ). This can be due to both physical and social obstacles that can affect the maintenance of this eating style.

The first barrier may be insufficient knowledge of the nutrients in a vegan diet, the principles of correct meal composition, or the implementation of supplementation ( 141 ). Another potential obstacle may be that veganism requires more dedicated time and commitment to cooking and preparing meals compared to meat-based options. This can be complicated by the perception that such a diet is tasteless and can easily become monotonous ( 142 ). Currently, the market offers a variety of meat and dairy substitutes that do not require much time to prepare ( 143 ). However, most plant-based meat alternatives are classified as ultra-processed foods (UPF) ( 144 ). Higher UPF intake is associated with an increased risk of obesity and diet-related non-communicable diseases (such as cardiovascular disease, diabetes, cancer) and even higher mortality ( 145 ).In addition, some people become attached to the taste of meat products, which can make it difficult to change eating habits, especially at the initial stage of changing their diet ( 146 ). One potential obstacle could be the difficulty of access to high-quality, fresh plant products and their higher cost compared to animal products ( 147 ). According to Fehér et al., meat prices have a clear impact on the willingness to switch to a plant-based diet ( 141 ).

Social pressure, especially from family, loved ones, and friends, is generally considered a significant influence on meat consumption. Some individuals may fear switching to a vegan diet because they expect stigma and ostracism from significant others ( 148 ). Adopting a vegan diet can affect family relationships, which may explain why those who choose this diet often experience a lack of understanding or even negative reactions from family members who consume animal products ( 149 ). Situations described as one of many factors seem to have an impact on mental health of people following a vegan diet, but scientific views on the impact of plant-based nutrition on mental health are divided. In the Dobersek et al. systematic review, the majority of studies, especially the higher-quality studies, found that people who avoided eating meat had significantly higher rates or risks of depression, anxiety and/or self-injurious behaviour ( 150 ). Forestell and Nezlek indicated that people who follow a plant-based diet are more likely to be depressed ( 151 ). Furthermore, women on a vegan diet are more likely than men to have disordered eating attitudes and practices ( 152 ).

One potential danger associated with a vegan diet is the risk of malnutrition, which can occur in individuals if the diet is not balanced and does not provide the body with sufficient essential nutrients. Although our review does not include studies on pregnant and breastfeeding women, it is worth mentioning that this is very important in the context of the impact on the fetus and child. According to international guidelines, a plant-based diet during pregnancy and lactation requires a high level of awareness to ensure complete intakes of essential key nutrients and vitamin supplements. Maternal undernutrition can potentially alter fetal growth trajectories by altering placental weight and nutrient transfer capacity, depending on the severity and timing of nutrient deprivation. Maternal malnutrition leading to vitamin B12, vitamin D, calcium and DHA deficiencies during lactation may contribute to low levels of these nutrients in breast milk ( 153 ).

Despite the barriers mentioned, many people successfully start and follow a vegan diet long-term and reap the health, ethical, and environmental benefits. Given the current growing interest in plant-based diets among the general population, it is crucial to understand both the barriers, risks, and benefits of such diets among clinicians, policy makers, and the general population ( 154 ). A food policy that combines health, sustainability, and affordability can effectively accelerate the promotion of plant-based diets and support the achievement of mitigation targets for potential barriers.

9. Conclusion

It is believed that a well-planned vegan diet, when combined with a healthy and active lifestyle, is a viable choice for healthy adults, especially those who follow it. This is because chronic diseases are significantly more common than they used to be and various strategies to address these public health challenges are insufficient.

Numerous studies have demonstrated the validity of this claim and any doubts have been attributed to an inadequately designed vegan diet, which is a potential problem with any kind of diet (such as omnivorous). As people age, their caloric needs tend to decrease, while their requirements for specific nutrients may increase.

A well-planned vegan diet must include adequate calories and nutrients, as well as the necessary supplements, such as vitamin B12 and vitamin D. To reduce the risk of vitamin deficiencies, fortified foods should be consumed by adults and the general population. Vegans are strongly encouraged to consult their doctors or dietitians before switching to a vegan diet.

Furthermore, the implementation of well-designed vegan diets and lifestyles requires greater awareness, greater social responsibility, and government involvement to ensure the fair cost of vegan food products. It should be emphasized that the advantages and drawbacks of vegan diets for adults are not fully covered in this review. The precise processes through which vegan diets work in many chronic diseases require further studies. Lastly, future studies should use large sample sizes that are accurately representative of the adult population.

Author contributions

EŁ: Conceptualization, Methodology, Resources, Writing – original draft, Writing – review & editing. FB: Conceptualization, Data curation, Methodology, Writing – original draft, Writing – review & editing. MZ: Data curation, Writing – original draft, Writing – review & editing. KD: Data curation, Resources, Writing – original draft, Writing – review & editing. AB: Data curation, Writing – review & editing. ŁO: Data curation, Writing – review & editing. AS: Data curation, Resources, Writing – review & editing.

The author(s) declare that no financial support was received for the research, authorship, and/or publication of this article.

Acknowledgments

We would like to express our sincere gratitude to Professor Gaëlle Arvisenet, for her valuable guidance and support throughout the research process. Her expertise, insights, and encouragement were invaluable in helping us to complete this work.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

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Keywords: bioactive compounds, health, plant-based sources, prevention, vegan diet

Citation: Łuszczki E, Boakye F, Zielińska M, Dereń K, Bartosiewicz A, Oleksy Ł and Stolarczyk A (2023) Vegan diet: nutritional components, implementation, and effects on adults’ health. Front. Nutr . 10:1294497. doi: 10.3389/fnut.2023.1294497

Received: 14 September 2023; Accepted: 30 October 2023; Published: 09 November 2023.

Reviewed by:

Copyright © 2023 Łuszczki, Boakye, Zielińska, Dereń, Bartosiewicz, Oleksy and Stolarczyk. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Edyta Łuszczki, [email protected] ;

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

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Vegetarianism Essay

This is a model  vegetarianism essay .

As I always stress, you should  read the question very carefully  before you answer it to make sure you are writing about the right thing.

Take a look at the question:

Every one of us should become a vegetarian because eating meat can cause serious health problems.

To what extent do you agree or disagree?

Staying on topic

If you rush to start writing and don't analyse the question and brainstorm some ideas you may include the wrong information.

There are religious or moral arguments for not eating meat, but if you discuss those you will be going off topic .

This question is specifically about the health problems connected to eating meat.

So you must discuss in your answer what some of these problems are and if you think there are real health risks or not.

Knowing about the topic

And don't get worried that you do not know much about diet and health.

As part of your IELTS study it will help if you know the basics of most topics such as some health vocabulary in this case, but you are not expected to be an expert on nutrition.

Remember, you are being judged on your English ability and your ability to construct an argument in a coherent way, not to be an expert in the subject matter. So relax and work with

Organisation

In this vegetarianism essay, the candidate disagrees with the statement, and is thus arguing that everyone does not need to be a vegetarian.

The essay has been organised in the following way:

Body 1: Health issues connected with eating meat (i.e. arguments in support of being a vegetarian Body 2: Advantages of eating meat

Now take a look at the model answer.

Model Essay

You should spend about 40 minutes on this task.

Write about the following topic:

Give reasons for your answer and include any relevant examples from your own experience or knowledge.

Write at least 250 words.

IELTS Vegetarianism Essay - Sample Answer

Vegetarianism is becoming more and more popular for many people, particularly because of the harm that some people believe meat can cause to the body. However, I strongly believe that it is not necessary for everybody to be a vegetarian.

Vegetarians believe that meat is unhealthy because of the diseases it has been connected with. There has been much research to suggest that red meat is particularly bad, for example, and that consumption should be limited to eating it just a few times a week to avoid such things as cancer. Meats can also be high in saturated fats so they have been linked to health problems such as cardiovascular disease and diabetes.

However, there are strong arguments for eating meat. The first reason is that as humans we are designed to eat meat, which suggests it is not unhealthy, and we have been eating meat for thousands of years. For example, cavemen made hunting implements so that they could kill animals and eat their meat. Secondly, meat is a rich source of protein which helps to build muscles and bones. Vegetarians often have to take supplements to get all the essential vitamins and minerals. Finally, it may be the case that too much meat is harmful, but we can easily limit the amount we have without having to cut it out of our diet completely.

To sum up, I do not agree that everyone should turn to a vegetarian diet. Although the overconsumption of meat could possibly be unhealthy, a balanced diet of meat and vegetables should result in a healthy body.

(264 words)

You should begin by intoducing the topi c. The introduction in this vegetarianism essay begins by mentioning vegetarians and the possible harm of eating meat .

It then goes on to the thesis statement , which makes it clear what the candidate's opinion is.

The first body paragraph has a topic sentence which makes it clear that the paragraph is going to address the possible health issues of eating meat.

Some reasons and examples are then given to support this.

The second body paragraph then has a topic sentence which makes it clear that the main idea is now about the arguments for eating meat .

The conclusion in this vegetarianism essay then repeats the opinion and gives the candidates final thoughts.

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85 Vegetarianism Essay Topic Ideas & Examples

For a vegetarianism essay, research paper, or speech, check out the titles our team has provided for you below.

📍 Great Research Questions about Vegetarianism

🏆 best vegetarianism essay topics & examples, 📌 interesting topics for essays on vegetarianism, 👍 good vegetarian essay topics.

• What are the key types of vegetarians?
• How do you get animal proteins as a vegetarian?
• Why do some people hate vegetarians?
• What are the ecological benefits of vegetarianism?
• Is a vegan diet affordable for the middle class?
• What are the health benefits of eating meat?
• Are there any unsolvable issues regarding a vegan diet?
• What is the best vegetarian food?
• How do you deal with the risk factors of a vegetarian diet?
• What are some myths about veganism?
• Vegetarianism Health Benefits It is going to be argued that; Being a vegetarian is good for health since it leads to the prevention of obesity and overweight, developing strong bones, prevention of heart disease, having cancer protection, having […]
• Vegetarian vs. Meat-Eating While meat is a rich source of essential minerals and vitamins, it also results in many adverse effects to the human body.
• Vegetarian or carnivorous diet However, a diet rich in meat and animal products has been found to have severe detrimental effects to people’s health. A well balanced diet that incorporates both meat and vegetables is essential.
• Why You Should Not Be a Vegetarian To conclude the above, it is important to note that vegetarianism refers to a form of food culture in which the individual eschews animal products.
• Vegetarianism and Its Causes The first cause to discuss is connected with economic reasons or the inability to include meat in everyday diet. Many vegetarians share the opinion that a meat-based diet is a sign of inhumanity.
• Consumer Behavior Theory: Vegetarianism If this philosophy is extrapolated to the vegetarianism trend analysis, the theory of reasoned action suggests that the rise in the number of vegetarians stems from people’s tendency to associate vegetarianism with good health.
• Benefits of Vegetarianism Cancer is one of the leading causes of death worldwide and in spite of enormous research efforts and many treatment options, there is still no guaranteed cure for the disease.anou and Svenson assert that in […]
• Worldwide Vegan Dairies: Digital Marketing Of particular importance is the promotion of vegan cheese in Australia, where information technology is also developed and the culture of a vegetarian lifestyle is flourishing.
• The Impact of Vegan and Vegetarian Diets on Diabetes Vegetarian diets are popular for a variety of reasons; according to the National Health Interview Survey in the United States, about 2% of the population reported following a vegetarian dietary pattern for health reasons in […]
• Harmfulness of Vegetarianism: The False Health Claim According to the article “How vegetarianism is bad for you and the environment”, “Plant-based sources tend to be low in saturated fat, a component of the brain and a macronutrient vital for human health”..
• Health 2 Go: Vegan Waffles for Everyone All fruits and berries are purchased daily from local suppliers and stored in a contaminant-free unit of the Health 2 Go.
• City’s Finest as a Vegan Ethical Shoe Brand The brand is focused on authenticity and transparency, producing the shoes locally and sourcing recycled and reclaimed materials that combine the principles of veganism and sustainability.
• Vegetarian Consumer Behaviour Raphaely states that the advances in agriculture created a threat to the environment, and it is important to study this situation in an in-depth manner.
• Vegetarian and Non Vegetarian Healthier Diet The first and foremost is that a vegetarian diet is one of the best weapons that can be used against overweight and obesity.
• Vegetarian Women and Prevention of Iron Depletion and Anemia Most of the body’s iron exists in hemoglobin, a quarter of the rest exists as metabolized iron-ferritin in the liver and the rest is found in the muscle tissue and selected enzymes.
• Vegetarian or Meat Eaters Contrary to the belief that meat is a great source of proteins, the quality of the protein in meat products is considered to be very poor since there is lack of proper combination of amino […]
• The Vegetarian Burger – A Product Review The burger also comes with significant nutrient components of Sodium and potassium.The total carbohydrate of the burger amounts to 6g which is 2% of the whole production unit.
• Vegetarian Diet and Proper Amount of Vitamins Issue This difference was accounted for by 14% lower zinc levels in the vegetarian diet and 21% less efficient absorption of zinc while eating it.
• Vegan Hot Dogs: Product Marketing The market for vegan hot dogs is a constantly growing market because the younger layer of the population is becoming more adherent to non-meat or vegan food sources.
• The Vegan Dog Kit Company’s Business Plan According to statistics, the number of vegetarianism in the United States is on the rise: as of 2018, five percent of the population adheres to a meatless diet, with half of them practicing veganism. Evidently, […]
• Pro-Vegetarianism to Save the Earth While most people agree that population growth is closely connected to the emission of greenhouse gases, which are harmful to the environment, as they lead to global warming, a rare individual believes that he or […]
• Can Vegetarian Diets Be Healthy? The analysis of the effectiveness of such a nutritional principle for the body can confirm, or, on the contrary, refute the theory about the advantages of vegetarianism and its beneficial effect on body functions.
• Moral Status of Animals: Vegetarianism and Veganism The significance of acknowledging the concept of sentience in this context is the fact that vegetarians and vegans accept the idea that animals are like humans when they feel something.
• “Quit Meat” Vegetarian Diet: Pros and Cons Although many dieticians think that meat is an essential nutrient, the reality is that it is inappropriate to eat animals because it is unhealthy and unethical.
• Vegan Parents’ Influence on Their Children’s Diet The first reason why a vegan diet should not be imposed on children is that every parent should pay close attention to the needs of their toddlers.
• Vegetarian Diet: Pros and Cons On the contrary, the study A Comparison of Some of the Cardiovascular Risk Factors in Vegetarian and Omnivorous Turkish Females by Karabudak, Kiziltan, and Cigerim portrayed that vegetarians had higher risks of hyperhomocysteinaemia and lower […]
• Positive Reasons and Outcomes of Becoming Vegan Being vegan signifies a philosophy and manner of living that aims at excluding, as much as achievable, any kind of exploitation of, and cruelty against, animals for meat, clothing and other uses while promoting and […]
• Herb’aVors Vegan Drive-Thru Product Business Model As a result, the wide public will be able to receive the brand-new service with the excellent health promotion characteristics and traditional cultural implications of fast-food. The breakthrough of the offered concept is the vegan-based […]
• Vegan vs. Vegetarian Diets: Impacts on Health However, vegetarians have the option of consuming animal products like eggs and milk, but this option is not available to vegans; vegetarians tend to avoid the intake of all the animal proteins.
• Vegetarianism Relation with Health and Religion These are the vegans, the lacto vegetarians, and the Lacto-ovo vegetarians. Apart from the explained contributions to health, vegetarian diets are also instrumental in checking blood pressure, aiding digestion, removal of body toxins and betterment […]
• Vegetarian Diet as a Health-Conscious Lifestyle Making a transition from omnivore to vegetarian lifestyle, besides the impact on the person’s health, people consider the public opinion and the community’s reaction on their decision.
• Target Market for the “Be Fine Vegan Skin Care” To be competitive in the market and realize profits from the sale of the product “Be Fine Vegan Skin Care” in a competitive market, marketing executives analyze and design a market plan that is strategically […]
• Today’s Society Should Move toward Adopting Vegetarian Diet: Arguments For While it is hard for many people to reduce the necessity of eat meat-based products and to increase the use of vegetables and other vegetarian products, however, there is a necessity “to reconsider the increasing […]
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• A History of Vegetarianism: Moral and Philosophy
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Vegan diet can be nutritious and tasty; here's all you need to know.

Published By : Nishad Thaivalappil

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Last Updated: September 07, 2024, 08:45 IST

Mumbai, India

A vegan diet can be varied and nutritious, but it requires careful planning to ensure it includes all essential nutrients,

Adopting a vegan diet can offer a range of benefits that span health, environmental impact and ethical considerations.

A vegan diet is a plant-based diet that excludes all animal products, including meat, dairy, eggs, and any other products derived from animals. Vegans also avoid honey and may steer clear of other animal-derived ingredients like gelatine or casein.

The country director, Veganuary India, Prashanth Vishwanath says, “Adopting a vegan lifestyle is one of the most powerful steps we can take to combat animal cruelty. We disconnect from the inhumane practices of agribusiness and spare countless animals from suffering. It’s not just a diet, it’s a stand for compassion and respect for all living beings. Going vegan empowers us to align our choices with our values and makes a real difference in the world.”

A vegan diet can be varied and nutritious, but it requires careful planning to ensure it includes all essential nutrients, such as vitamin B12, vitamin D, iron, calcium, omega-3 fatty acids, and protein. Adopting a vegan diet can offer a range of benefits that span health, environmental impact and ethical considerations.

Here are some health benefits:

Improved Heart Health

Vegan diets are often low in saturated fats and cholesterol, which can help reduce the risk of heart disease. The high intake of fruits, vegetables, and whole grains provides beneficial nutrients that support cardiovascular health.

Lower Risk of Type 2 Diabetes

Research suggests that a vegan diet may help lower the risk of developing type 2 diabetes due to its emphasis on whole, plant-based foods that help manage blood sugar levels and improve insulin sensitivity.

Weight Management

Many people find that a vegan diet aids in weight management or weight loss. Plant-based diets are generally lower in calories and fat while being high in fiber, which promotes satiety.

Enhanced Digestive Health

Due to its high fiber content, it supports healthy digestion, promotes regular bowel movements, and can help prevent constipation and other digestive issues.

Reduced Risk of Certain Cancers

Some studies indicate that vegan diets may lower the risk of certain cancers, particularly those related to digestive organs, due to high intakes of fruits, vegetables, and whole grains which are rich in antioxidants and phytochemicals.

Better Skin Health

Many people report clearer skin and a healthier complexion on a vegan diet, possibly due to reduced intake of dairy and processed foods, which can be linked to acne and other skin issues.

Increased Longevity

Evidence suggests that a vegan diet may contribute to a longer life span. This is often linked to the diet’s association with reduced risks of chronic diseases and overall healthier living.

Environmental Benefits

Vegan diets have a lower environmental impact compared to diets that include animal products. They contribute to reduced greenhouse gas emissions, less water usage, and lower levels of deforestation and habitat destruction.

Ethical Considerations

A vegan diet aligns with ethical concerns about animal welfare by avoiding the exploitation and harm of animals for food. It supports more humane treatment of animals and reflects a commitment to animal rights.

Increased Energy Levels

Many people experience increased energy levels on a vegan diet due to the consumption of nutrient-dense foods. The focus on whole plant foods can provide sustained energy throughout the day.

According to the Associate Director and Head – Internal Medicine, Asian Hospital, Faridabad, Dr. Sunil Rana, “A vegan diet that’s full of fruits and veggies has helped many lose extra pounds and maintain a healthy weight. Of course, there are tons of vegan junk food options in stores, so be sure to stay away from processed foods if you really want to kick your weight loss to the next level.”

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