The role of anxiety and depressive symptoms in the longitudinal relationship between body image and disordered eating behaviors among Tibetan young adults: a moderating serial mediation model

Abstract

Background: Body image significantly impacts emotional and behavioral health. This study investigates the relationship between body image dissatisfaction and disordered eating behaviors (DEBs) among Tibetan young adults, considering the mediating roles of anxiety and depression and the moderating role of ethnicity. Methods: A longitudinal survey was conducted among 2993 first- and second-year university students in Tibet, with initial data collection in September 2021 and follow-up in December 2021. Participants completed standardized questionnaires assessing body image, anxiety, depression, and DEBs. Statistical analyses included t-tests, ANOVA, Pearson correlation, and moderated serial mediation using the PROCESS macro. Results: Body image satisfaction significantly negatively predicted DEBs (β= -0.031, 95% CI = -0.061~-0.001). Anxiety and depression independently and sequentially mediated this relationship (a₁b₁ = -0.008, 95% CI = -0.015~-0.001; a₂b₂ = -0.005, 95% CI = -0.010~-0.001; a₁db₂ = -0.017, 95% CI = -0.026~-0.009). Ethnicity moderated the direct effect, with body image significantly predicting DEBs among Tibetan students but not Han Chinese students. Conclusions: This study highlights the critical roles of anxiety and depression in the link between body image and DEBs and the moderating effect of ethnicity. These findings suggest targeted interventions addressing body image and emotional health to mitigate DEBs, especially in ethnic minority populations.