Weight Bias Internalization and Long-Term Weight Loss in Patients With Obesity

The relationship between weight bias internalization (WBI) and long-term weight loss is largely unknown.

To determine the effects of weight loss on WBI and assess whether WBI impairs long-term weight loss.

One hundred thirty-three adults with obesity completed the Weight Bias Internalization Scale (WBIS) at baseline, after a 14-week lifestyle intervention in which they lost ≥5 per cent of initial weight, and at weeks 24 and 52 of a subsequent randomized controlled trial (RCT) for weight-loss maintenance (66 weeks total). Linear mixed models were used to examine the effects of weight loss on WBIS scores and the effects of baseline WBIS scores on weight change over time. Logistic regression was used to determine the effects of baseline WBIS scores on achieving ≥5 and ≥10 per cent weight loss.

Changes in weight did not predict changes in WBIS scores. Baseline WBIS scores predicted reduced odds of achieving ≥5 and ≥10 per cent weight loss at week 24 of the RCT (p values < .05). At week 52, the interaction between participant race and WBIS scores predicted weight loss (p = .046) such that nonblack (but not black) participants with higher baseline WBIS scores had lower odds of achieving ≥10 per cent weight loss (OR = 0.38, p = .01). Baseline WBIS scores did not significantly predict rate of weight change over time.

Among participants in a weight loss maintenance trial, WBI did not change in relation to changes in weight. More research is needed to clarify the effects of WBI on long-term weight loss and maintenance across race/ethnicity.

ClinicalTrials.gov identifier NCT02388568.