Vegetarian diet and orthorexia nervosa: a review of the literature

Eat Weight Disord. 2021 Feb;26(1):1-11. doi: 10.1007/s40519-019-00816-3. Epub 2019 Nov 29.


Background: The number of individuals following a vegetarian diet has increased in the last 50 years. Although the causal connection between orthorexic behaviors and vegetarianism remains widely assumed, evidence in support of this assumption has been largely inconsistent.

Objective: The purpose of the study was to conduct a review of the relationship between vegetarian diet and orthorexic eating behavior and to give future directions in this area.

Methods: A search of the literature within PubMed/Medline was conducted. The search terms were "orthorexia", "orthorexic", "orthorexia and vegetarian", "orthorexia and vegan" and "orthorexia and vegetarianism". Out of 117 journal articles, 14 met the predefined inclusion criteria and were analyzed.

Results: The results demonstrated that following a vegetarian diet was found to be related to orthorexic eating behaviors (in 11 out of 14 studies).

Conclusion: Further longitudinal research is needed to investigate whether following a vegetarian diet serves as a risk factor in the development of orthorexia nervosa.

Level of evidence: Level V, narrative review.

Keywords: Eating behaviors; Orthorexia nervosa; Vegan diet; Vegetarian diet.

Publication types

  • Review

MeSH terms

  • Diet, Vegan
  • Diet, Vegetarian*
  • Feeding Behavior
  • Feeding and Eating Disorders* / etiology
  • Humans
  • Vegans
  • Vegetarians