Exploring longitudinal associations between thinness- and muscularity-oriented eating and body image disturbances in Chinese adult women and men

Individuals striving for socially promoted thin and muscular body ideals are at risk of developing thinness- and muscularity-oriented eating and body image disturbances. Thinness and muscularity are not mutually exclusive but rather interconnected components of contemporary body ideals. However, prior studies have largely examined these associations within each category (e.g., body fat dissatisfaction with thinness-oriented disordered eating or muscularity dissatisfaction with muscularity-oriented disordered eating), which neglects potential cross-category relationships. The present study, which addressed this research gap, explored these cross-category longitudinal associations at baseline (T1) and 6 months later (T2). Employing gender-specific cross-lagged models, we analyzed data from an online sample of 799 Chinese women and men. We examined four cross-category reciprocal relationships: (1) body fat dissatisfaction with muscularity dissatisfaction, (2) body fat dissatisfaction with muscularity-oriented disordered eating, (3) thinness-oriented disordered eating with muscularity dissatisfaction, and (4) thinness-oriented disordered eating with muscularity-oriented disordered eating. Results revealed gender-specific cross-category associations. Particularly, positive, bidirectional associations were observed among women between thinness- and muscularity-oriented eating and body image disturbances. Among men, the associations were unidirectional, with muscularity-oriented eating and body image disturbances at T1 predicting greater thinness-oriented disordered eating at T2, but not vice versa. These findings advanced existing knowledge of the cross-category relationships between thinness- and muscularity-oriented eating and body image disturbances, with important implications for gender-specific interventions in non-clinical adults. For women, programs should address the reciprocal reinforcement between thinness- and muscularity-oriented eating and body image disturbances, while for men, targeting muscularity-oriented disturbances may help reduce subsequent thinness-oriented disordered eating.