Light and Food: Body Image Moderates the Effects of Chronotype on the Risk to Develop an Eating Disorder.

Background: Evening chronotypes are increasingly recognized as being at elevated risk of psychological vulnerabilities, including sleep disturbances, mood disorders, and disordered eating. Body image, a central self-related construct, has been identified as a key factor influencing eating disorder (ED) risk. This study aimed to explore whether body image moderates the relationship between chronotype and the risk of developing an ED. Methods: A total of 165 adults (139 women; mean age = 35.45) completed validated self-report questionnaires assessing chronotype (Morningness-Eveningness Questionnaire), body image (Body Shape Questionnaire), and ED risk (EAT-26). Pearson correlations and moderation analyses (PROCESS macro and Model 1) were conducted with body image as a moderator of the association between chronotype and ED risk. Results: Eveningness was significantly associated with greater ED risk (r = -0.53, p < 0.001) and a more negative body image (r = -0.48, p < 0.001). Body image was a strong predictor of ED risk (r = 0.85, p < 0.001). Moderation analysis revealed a significant interaction between chronotype and body image (b = -0.006, SE = 0.0009, p < 0.001), indicating that the relationship between chronotype and ED risk was stronger among individuals with a more negative body image. Conclusions: These findings highlight the role of body image as a moderating factor in the link between chronotype and eating disorder vulnerability. Interventions aimed at improving body image, especially among evening chronotypes, may help mitigate ED risk. These results underscore the importance of integrating circadian and psychosocial factors in ED prevention and early intervention strategies.