Multiple Health Benefits and Minimal Risks Associated with Vegetarian Diets
Purpose of Review
Understand the current prevalence, health benefits, and health risks of vegetarian diets.
Since the publishing of the Adventist Health Study 2 in 2013, there have been several prospective diet studies demonstrating and challenging the health benefits and risks of the vegetarian diet.
The definition of the vegetarian diet has become more specific over time and requires standardization for research purposes. Despite an uptrend in sales rates of plant-based foods per year, a 2018 Gallup poll showed overall stagnation of the percentage of self-reported vegetarians and vegans compared to percentages obtained 6 years prior. Compared to the Adventist Health Study, more recent vegetarian diet studies have demonstrated significant although smaller risk reductions for mortality in cardiovascular disease, cerebrovascular disease, diabetes mellitus, and chronic kidney disease. Recent studies have correlated certain food groups with early death or increased longevity. In addition, the vegetarian health risks of deficiencies of protein, omega-3 fatty acids, vitamin D, vitamin B12, iron, calcium, and zinc are explored.
KeywordsVegetarian Vegan Plant-based Diet Healthy Benefits Cardiovascular Cerebrovascular Diabetes mellitus Chronic kidney disease Protein Omega-3 Fatty acids Vitamin D Vitamin B12 Iron Calcium Zinc Flexitarian Plant-based Whole food
Compliance with Ethical Standards
Conflict of Interest
Jason P. Rocha, Janese Laster, Bhavyata Parag, and Nihar U. Shah declare they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: •• Of major importance
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