Multiple Health Benefits and Minimal Risks Associated with Vegetarian Diets

  • Jason P. RochaEmail author
  • Janese Laster
  • Bhavyata Parag
  • Nihar U. Shah
Gastroenterology, Critical Care, and Lifestyle Medicine (SA McClave, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Gastroenterology, Critical Care, and Lifestyle Medicine


Purpose of Review

Understand the current prevalence, health benefits, and health risks of vegetarian diets.

Recent Findings

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.


Vegetarian 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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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  • Jason P. Rocha
    • 1
    Email author
  • Janese Laster
    • 2
  • Bhavyata Parag
    • 3
  • Nihar U. Shah
    • 4
  1. 1.Division of Gastroenterology and NutritionUniversity of Texas Health San AntonioSan AntonioUSA
  2. 2.Division of GastroenterologyGeorgetown University HospitalWashingtonUSA
  3. 3.Department of PharmacyHouston Methodist Clear LakeHoustonUSA
  4. 4.Division of Gastroenterology, Hepatology, and NutritionUniversity of LouisvilleLouisvilleUSA

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