Longitudinal associations of binge eating with internalized weight stigma and eating self-efficacy.

INTRODUCTION: Internalized weight stigma (IWS) is linked to binge eating disorder (BED) symptoms and reduced self-efficacy, yet it unknown how changes in these factors may interrelate. The current study examined cross-sectional and longitudinal associations of BED with IWS and eating self-efficacy among treatment-seeking adults with high body weight. Disinhibited eating was explored as a mediator.

METHODS: Seventy-one adults with high weight and elevated IWS were included in this secondary analysis of a clinical trial that provided 26 weeks of behavioral weight loss (BWL) treatment with (versus without) an additional IWS intervention. Participants underwent a BED diagnostic interview at screening and completed validated measures of binge eating, IWS (including weight bias internalization, self-devaluation, and stereotype endorsement), eating self-efficacy, and disinhibited eating at baseline and week-26. Cross-sectional mediation models tested associations of BED with IWS and eating self-efficacy, explained by disinhibited eating. Linear and logistic regression models, controlling for treatment condition, tested if baseline BED predicted changes in IWS, self-efficacy, and disinhibited eating, and if decreased binge episodes were associated with improved outcomes.

RESULTS: At baseline, disinhibited eating mediated the relationship between BED and weight self-devaluation (95 % CI = 0.66,3.58), stereotype endorsement (CI = 0.15,0.56), and eating self-efficacy (CI:-14.40,-4.29). Baseline BED did not predict changes in outcomes. Participants with decreased binge episodes reported greater improvements in weight bias internalization (p = 0.04) and eating self-efficacy (p < 0.001).

CONCLUSION: This study provides novel evidence of longitudinal associations between binge eating, IWS, and eating self-efficacy. IWS warrants further consideration as a treatment target and outcome in studies of BWL and BED.