A prospective evaluation of internalized weight bias and weight change among successful weight loss maintainers

OBJECTIVE: Internalized Weight Bias (IWB) is associated with weight regain after intentional weight loss, but reliance on cross-sectional data limits our understanding of this relationship. This study prospectively evaluated IWB as a predictor of weight change in a longitudinal observational study of successful weight loss maintainers. METHODS: National Weight Control Registry participants (maintained 13.6 kg weight loss for ≥ 1 year) were asked to complete an online questionnaire at baseline and 12 months including current weight and Weight Bias Internalization Scale-Modified (WBIS-M). RESULTS: At baseline, 1250 of 1643 eligible individuals completed the baseline assessment (71% female, 94% white, mean± SD age: 52yrs.±13.1, BMI: 27±5.5). Average WBIS-M score was 3.0 (±1.3). Study completers (n=862) reported 2.2% (±7.8) weight gain. Higher baseline IWB predicted weight gain among men (n=254, t=−2.28, p=.02) but not women (n=608, t=1.22, p=.22). A one point reduction in WBIS-M score at follow-up was associated with a 3.0% weight loss. CONCLUSIONS: Among weight loss maintainers, IWB may be a risk factor for weight gain among men. Weight loss at follow-up was associated with reduced IWB in both men and women. Reliance on female-only samples may limit our understanding of IWB and its implications for weight control.