Orthorexia Nervosa (ON) is a condition involving a pathological obsession with healthy or “clean” eating (Bratman, 1997). Prevalence estimates of ON range from 35.4% to 83% in the U.S. population (Niedzielski & Kaźmierczak-Wojtás, 2021). Starting out innocuously as a habit of eating healthier foods, ON becomes socially and physically impairing when individuals spend a large amount of time and effort planning and preparing healthy meals, eventually turning into an obsession that interferes with other domains of life (Oberle et al., 2017). Although ON is not in the DSM-5, preliminary investigation has shown that it may fall on the eating disorder spectrum – either as a precursor or a residual form (Segura-Garcia et al., 2015). Only limited cross-sectional studies have examined the psychosocial factors related to ON (McCombs & Mills, 2019). The purpose of the present study was to test the extent to which daily stress and negative affect predicted ON behavior in college students, as well as the moderating effects of perfectionism and an already healthy diet on these relations. Moreover, we also tested the predictive effect of negative appearance-focused family cultures on concurrent levels of ON symptoms. Results from hierarchical linear modeling found that when participants experienced higher stress intensity levels than usual, they engaged in more ON behaviors on the same day. Neither perfectionism nor an already healthy diet moderated this relation. Within-person associations between negative affect and ON were not significant. Regression models found that higher negative appearance-focused comments and behaviors in families predicted higher levels of baseline ON symptoms, over and above perfectionism, obsessive-compulsive tendencies, past dieting, current/past eating disorders, and neuroticism. The findings can inform intervention and preventive work in ON, which has no empirically-tested treatment yet.

Degree Date

Fall 12-16-2023

Document Type


Degree Name





Chrystyna D. Kouros, PhD

Number of Pages




Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

Appendix A.docx (38 kB)