Mental health research in vegans and vegetarians: a critical commentary on ethics, empathy, and epidemiology

Comparisons between vegans and omnivores

This paper critiques the widespread use of epidemiological comparisons between vegans and omnivores in mental health research. It highlights that while such studies often attribute mental health outcomes to nutritional deficiencies or benefits, they frequently overlook significant psychosocial and ethical factors. These include elevated empathy, social stigma, and inconsistent dietary classifications, which undermine causal inference and render the observational findings conceptually flawed. Furthermore, analyses focused on the vegan population regarding diet quality provide more valid insights. The authors argue for future research to incorporate targeted psychological screening to better capture the unique ethical and social stressors associated with veganism. This approach is suggested to enhance the accuracy and relevance of mental health assessments in both research and policy contexts. [NPID: Vegan, vegetarian, omnivores, mental health, dietary, policy, nutritional]

Year: 2026

Reference: Campbell, J. L. (2026). Mental health research in vegans and vegetarians: A critical commentary on ethics, empathy, and epidemiology. Appetite, 217, 108348. https://doi.org/10.1016/j.appet.2025.108348