The Pros and Cons of Vegan Diets

A research article reviewed studies on the health effects of vegan diets (Winston J Craig, 2009). A vegan diet completely avoids eating any meat, dairy, eggs or animal-derived products. The article explains that vegan diets tend to be higher in fiber, vitamins C and E, magnesium, folic acid and beneficial plant compounds. They also tend to be lower in saturated fat, cholesterol and calories. Multiple studies have shown vegans generally have a lower body mass index, body weight, blood cholesterol and blood pressure compared to non-vegans and other vegetarians. This likely contributes to vegans’ lower risk of cardiovascular disease, obesity and type 2 diabetes.

The article highlights evidence that vegans typically consume more fruits, vegetables, whole grains, nuts and legumes than non-vegans. The high amounts of beneficial nutrients and compounds in these plant foods are linked to lower risks of certain cancers and chronic diseases. For example, the fiber, potassium and antioxidants found in fruits and veggies protect the heart. Whole grains and nuts also improve cardiovascular health. Soy products and legumes contain compounds that may lower chances of prostate, breast and other cancers. Compared to meat-eaters, vegans also avoid consuming red meat and eggs, which are tied to higher incidences of some cancers.

In terms of bone health, studies show long-term vegans have similar or slightly lower bone mineral density on average. However, vegans who consume adequate amounts of calcium and vitamin D do not appear to have any higher fracture risk. A vegan diet high in fruit, vegetables, calcium and vitamin K contains compounds and nutrients beneficial for bone density.

Potential nutritional shortfalls for vegans include vitamins B12 and D, omega-3 fatty acids, iron, zinc and calcium. Eating fortified foods or taking supplements can help vegans obtain adequate amounts of these nutrients. With appropriate food choices or supplementation, vegans are able to avoid nutritional deficiencies.

Overall, the article concludes well-planned vegan diets provide comparable health outcomes or benefits over other vegetarian and non-vegetarian diets. More studies comparing the effects of different types of vegetarian diets are still needed. But current evidence shows vegans generally have a lower risk of obesity, cardiovascular disease, type 2 diabetes and some cancers than non-vegans.

Craig WJ. Health effects of vegan diets. Am J Clin Nutr. 2009 May;89(5):1627S-1633S. PMID: 19279075 DOI: 10.3945/ajcn.2009.26736N