ABSTRACT
BACKGROUND: Overvaluation of body shape/weight is thought to be the core psychopathology underlying eating disorders, which propels engagement in non-compensatory weight-control behaviors. In turn, these behaviors lead to binge eating and/or maintenance of low weight thereby reinforcing overvaluation. The present study investigated the reciprocal relationship between overvaluation and engagement in non-compensatory weight-control behaviors (defined in two ways: restrictive eating and compulsive exercise) among women diagnosed with anorexia nervosa or bulimia nervosa (N = 237). METHOD: Participants completed clinical interviews in which weekly eating disorder symptoms and behaviors were assessed over 2 years. RESULTS: Overvaluation on a given week was associated with greater engagement in non-compensatory weight-control behaviors during the following week. Further, engagement in non-compensatory weight-control behaviors on a given week was associated with greater overvaluation during the following week. These findings held true regardless of participants' shape/weight concerns (feelings of fatness and fat phobia), and eating disorder diagnosis. CONCLUSIONS: Our data provide empirical support for key aspects of the transdiagnostic cognitive-behavioral model of eating disorders and suggest that targeting non-compensatory weight-control behaviors in treatment may help alleviate overvaluation and shape/weight concerns.