By Joseph E. Scherger, MD, MPH

Core Faculty, Eisenhower Health Family Medicine, Residency Program, Eisenhower Health Center, La Quinta, CA; Clinical Professor, Keck School of Medicine, University of Southern California, Los Angeles

Dr. Scherger reports no financial relationships relevant to this field of study.

SYNOPSIS: In a large, prospective study of men and women in the United Kingdom, those following a vegan diet sustained more total and hip fractures than those eating animal products.

SOURCE: Tong TYN, Appleby PN, Armstrong MEG, et al. Vegetarian and vegan diets and the risks of total and site-specific fractures: Results from the prospective EPIC-Oxford study. BMC Med 2020;18:353.

Tong et al analyzed the data of men and women in the United Kingdom that were collected at baseline (between 1993 and 2001) and at follow-up (around 2010) as part of the EPIC-Oxford study. The information gathered concerned participants’ dietary habits. The authors identified four groups based on their diets: 29,380 meat eaters (full omnivore diet), 8,807 fish eaters (no meat intake), 15,499 vegetarians (ate one or both of eggs or dairy), and 1,982 vegans (plant foods only). Adjustments were made for socioeconomic, body mass index, and other lifestyle factors.

Meat eaters exhibited the lowest risk for hip fractures, with some increased risk for fish eaters (hazard ratio, 1.26) and vegetarians (hazard ratio, 1.25). Vegans were much more likely to sustain hip fractures (hazard ratio, 2.31) vs. meat eaters. Vegans also were at higher risks for total and other site fractures vs. meat eaters.

COMMENTARY

Advocates for exclusive plant-based diets are quite vocal. They cite studies showing how eating only plants results in lower cancer rates and all-cause mortality.1,2 The American College of Lifestyle Medicine strongly advocates for plant-based diets among its leaders.3 Many vegans and vegetarians believe eating animal products is unhealthy, even immoral, and bad for the environment.

Evolutionary biologists note Homo sapiens survived through omnivorous habits, and that our large brains and intestinal tracts reflect eating animal foods.4,5 Studies have shown vegetarians exhibit lower bone mineral density than nonvegetarians.6 Vegan diet adherents intake less calcium and protein,7 and vegans often record a lower body mass index.8 One author who lived for 20 years as a staunch vegan shared details about the musculoskeletal complications she suffered as a result of eating only plant foods.9

Living as a vegan or vegetarian is a choice and can benefit one’s health. However, clinicians should educate patients about potential risks, including bone fractures. Appropriate supplementation might prevent these complications.

REFERENCES

  1. Greger M, Stone G. How Not to Die: Discover the Foods Scientifically Proven to Prevent and Reverse Disease. Flatiron Books; 2015.
  2. Campbell TC, Jacobson H. Whole: Rethinking the Science of Nutrition. BenBella Books; 2014.
  3. American College of Lifestyle Medicine. About.
  4. Lieberman D. The Story of the Human Body: Evolution, Health and Disease. Pantheon; 2013
  5. Saladino P. Carnivore Code: Unlocking the Secrets to Optimal Health by Returning to Our Ancestral Diet. Lifestyle; 2020.
  6. Ho-Pham LT, Nguyen ND, Nguyen TV. Effect of vegetarian diets on bone mineral density: A Bayesian meta-analysis. Am J Clin Nutr 2009;90:943-950.
  7. Davey GK, Spencer EA, Appleby PN, et al. EPIC-Oxford: Lifestyle characteristics and nutrient intakes in a cohort of 33,883 meat-eaters and 31,546 non meat-eaters in the UK. Public Health Nutr 2003;6:259-268.
  8. Spencer EA, Appleby PN, Davey GK. Diet and body mass index in 38,000 EPIC-Oxford meat-eaters, fish-eaters, vegetarians and vegans. Int J Obes Relat Metab Disord 2003;27:728-734.
  9. Keith L. The Vegetarian Myth: Food, Justice, and Sustainability. Flashpoint; 2009.