An inflexible adherence to food rules mediates the longitudinal association between shape/weight overvaluation and binge eating.

Understanding factors that account for the persistence of binge eating is necessary for developing effective early intervention and treatment approaches. The cognitive-behavioral model of eating disorders proposes that judgements of self-worth contingent upon weight and shape encourage adoption of multiple demanding rules related to food, eating and dieting, in turn increasing vulnerability to binge eating. However, there is limited longitudinal evidence supporting this hypothesized sequence of events. This study tested whether the longitudinal association between shape/weight overvaluation and binge eating is mediated by an inflexible adherence to food rules. Participants were 1760 adult women recruited from an online eating disorder platform who were invited to complete study measures at baseline (T1), 3-month follow-up (T2), and 6-month follow-up (T3). Path analysis was conducted to test the hypothesized associations. Missing data were handled using multiple imputation techniques. A significant indirect effect emerged, in that higher overvaluation scores at T1 predicted increased inflexible adherence to food rules at T2, which in turn predicted increased binge eating symptoms at T3. Findings offer support for the predictions outlined by the cognitive-behavioral model of eating disorders and highlight clear targets for early intervention and treatment.