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Revision #31 (current version) as edited by itsvegan editors on Thu, Oct 29, 2026 · 10:03 · “Initial version by the itsvegan editors”

Vegan diet and health

The relationship between a vegan diet and health has been studied mainly through large observational cohort studies, along with smaller clinical trials. This article summarises the main findings cautiously. Most long-term studies group vegans with other vegetarians, and observational research cannot by itself prove cause and effect, because vegans may differ from other people in ways such as smoking, alcohol use, exercise and body weight.

Professional positions

In 2016 the Academy of Nutrition and Dietetics stated that appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases. The paper reported that these diets are associated with a lower risk of ischaemic heart disease, type 2 diabetes, hypertension, certain types of cancer and obesity. The British Dietetic Association and other bodies have made similar statements about well-planned vegan diets. At the same time, these organisations stress that vegan diets must include reliable sources of certain nutrients, particularly vitamin B12.

Major studies

  • EPIC-Oxford is a UK cohort, part of the European Prospective Investigation into Cancer and Nutrition, that recruited tens of thousands of participants in the 1990s, including a large number of vegetarians and vegans.
  • Adventist Health Study-2 is a North American cohort of Seventh-day Adventists, a population with a wide range of dietary patterns, including many vegetarians and vegans.

Heart disease and stroke

Vegan diets typically contain little saturated fat and no dietary cholesterol, and are high in fibre. Studies consistently find that vegans have lower average LDL cholesterol levels and lower blood pressure than meat eaters.

A 2019 analysis of EPIC-Oxford data published in The BMJ found that vegetarians, including vegans, had a lower risk of ischaemic heart disease than meat eaters, reported as roughly 22% lower. The same analysis found a higher risk of haemorrhagic and total stroke among vegetarians and vegans. The authors noted that the stroke finding needed further research and might relate to factors such as low blood cholesterol or low levels of certain nutrients, including vitamin B12.

Type 2 diabetes

Data from the Adventist Health Study-2 showed a lower prevalence of type 2 diabetes among vegans than among non-vegetarians, even after accounting for body mass index. Clinical trials have also tested low-fat vegan diets in people with type 2 diabetes and reported improvements in blood glucose control and body weight. Lower body weight among vegans appears to explain part, but possibly not all, of the association.

Cancer

Evidence on cancer is more limited and less consistent. Some analyses from the Adventist Health Study-2 and EPIC-Oxford have reported modestly lower overall cancer incidence among vegetarians or vegans, but findings for individual cancers are often uncertain because of small numbers of cases.

Relevant context includes the 2015 evaluation by the International Agency for Research on Cancer (IARC), which classified processed meat as carcinogenic to humans (Group 1) and red meat as probably carcinogenic to humans (Group 2A), mainly on the basis of colorectal cancer evidence. Diets high in fibre, whole grains, fruit and vegetables are also associated with lower risk of some cancers. However, it is not established that a vegan diet as such prevents cancer.

Bone health

Bone health is an area of concern. EPIC-Oxford analyses have found a higher risk of fractures among vegans than meat eaters. A 2020 analysis published in BMC Medicine reported higher risks of total, hip, leg and vertebral fractures in vegans. Researchers suggested that lower calcium and protein intakes and lower body mass index may contribute. An earlier analysis found that the higher fracture risk was not seen among vegans with adequate calcium intakes. Adequate calcium, vitamin D and protein, and regular weight-bearing exercise, are therefore emphasised.

Diet quality matters

Not all vegan diets are equal. Research by Harvard researchers using “plant-based diet indices” has distinguished between healthful plant-based diets, rich in whole grains, fruit, vegetables, nuts and legumes, and unhealthful ones high in refined grains, sugary drinks and sweets. Healthful patterns were associated with lower risk of heart disease and type 2 diabetes; unhealthful ones were not. See plant-based vs vegan.

Nutrients requiring attention

Health organisations commonly highlight the following nutrients for vegans:

  1. vitamin B12 – supplementation or fortified foods are essential.
  2. vitamin D – especially in winter at higher latitudes.
  3. iodine – often low without iodised salt or fortified foods.
  4. calcium – important for bone health.
  5. Omega-3 fatty acids – long-chain EPA and DHA.
  6. iron and zinc – absorption is lower from plant foods.

This article summarises research for general information and is not medical advice. Individuals should consult a doctor or registered dietitian for personal advice.

See also