Behavioral Weight Loss Treatment Promotes Weight Loss by Increasing Eating Disorder Symptoms: A Response to Grilo & Pittman (2024).

We provide commentary on the Grilo and Pittman (2024). Exploring Dietary Restraint as a Mediator of Behavioral and Cognitive-Behavioral Treatments on Outcomes for Patients With Binge-Eating Disorder With Obesity article published in the International Journal of Eating Disorders. Grilo and Pittman show that weight loss in the Behavioral Weight Loss Treatment condition is mediated by an increase in rigid restraint, whereas binge eating is not mediated by rigid restraint. They conclude that this result is a positive outcome for patients with binge-eating disorder and shows that BWL is not harmful in this population. We argue that increasing rigid restraint equates to increasing eating disorder symptoms and is harmful in any population, but specifically in those with an already diagnosed eating disorder. In addition, we point out the major limitations of no follow-up data in the mediation report, no measurement of additional eating disorder symptoms that could represent diagnostic migration, and lack of inclusion of weight stigma as additional problems with the stated conclusions. We recommend that the field moves away from measurement of weight loss as an outcome in those with eating disorders and carefully consider what it means to increase restraint/restriction in eating disorder populations.