Eating Disorder Risk, Healthy Orthorexia, and Orthorexia Nervosa Among Women Following Vegan, Vegetarian, and Omnivorous Dietary Patterns in Türkiye: A Cross-Sectional Study

Background/Objectives: Food exclusions in vegan and vegetarian diets may complicate the assessment of disordered eating and orthorexia. This study compared eating disorder risk, healthy orthorexia, and orthorexia nervosa across vegan, vegetarian, and omnivorous women and examined their adjusted associations with dietary pattern. Methods: This cross-sectional study used convenience sampling to recruit 305 women in Türkiye who self-identified as vegan (n = 64), vegetarian (n = 71), or omnivorous (n = 170). Participants completed the Eating Attitudes Test-26, Teruel Orthorexia Scale, and Food Choice Questionnaire. Associations with vegan and vegetarian patterns were examined using multinomial logistic regression, with omnivorous women as the reference group. Potential nonlinearity in the association between orthorexia nervosa and the vegan versus omnivorous contrast was examined using restricted cubic splines. Secondary exploratory food choice models were corrected for multiple testing. Results: Elevated eating disorder risk was not significantly associated with either the vegan or vegetarian pattern in the adjusted model. Higher healthy orthorexia scores were associated with greater odds of following a vegan pattern (adjusted odds ratio (aOR) = 1.177, 95% confidence interval (CI): 1.090–1.270), whereas the association between orthorexia nervosa and the vegan pattern was nonlinear (p for nonlinearity = 0.006), with the adjusted probability declining across low-to-moderate scores and the estimates becoming imprecise at higher scores. Neither orthorexia dimension was associated with the vegetarian pattern. In secondary exploratory analyses, weight control motivation was associated with lower odds of vegan (aOR = 0.424, 95% CI: 0.249–0.723) and vegetarian patterns (aOR = 0.610, 95% CI: 0.382–0.975), while familiarity was associated with lower odds of the vegan pattern (aOR = 0.466, 95% CI: 0.296–0.735). Conclusions: Healthy orthorexia and orthorexia nervosa showed distinct associations with the vegan pattern. Dietitians and healthcare professionals should not infer eating pathology from dietary pattern labels alone but should consider motivations for food exclusions, weight- and shape-related concerns, dietary rigidity, distress, and functional impairment.