Investigating the effect of a cognitive-behavioral therapy intervention aimed at reducing weight self-stigma on adherence to weight loss diet and anthropometric indices in adult women with obesity: study protocol for a randomized controlled trial.

Abstract

Background: Obesity is a complex and chronic condition with serious health risks, including higher chances of diabetes, heart disease, and certain types of cancer. Weight self-stigma, prevalent among individuals with obesity, exacerbates psychological distress and negatively impacts adherence to weight loss diets. Cognitive-behavioral therapy (CBT), a psychological intervention targeting maladaptive beliefs and behaviors, has shown promise in addressing weight self-stigma. However, the specific impact of CBT, delivered in a group therapy format, on adherence to prescribed weight-loss diets has not yet been adequately investigated, particularly among women with obesity, who are disproportionately affected by both the condition and weight self-stigma.

Methods: This research is a two-arm, parallel-group randomized controlled trial aimed at assessing the effectiveness of a group-based CBT intervention in mitigating weight self-stigma and enhancing adherence to a weight-loss diet and anthropometric outcomes in adult women with obesity. Participants (n = 120) who meet the inclusion criteria will be randomly allocated to one of two groups: (1) CBT in addition to a personalized weight-loss diet, or (2) only the personalized weight-loss diet. The CBT intervention will consist of 1.5-h weekly online group therapy sessions over 12 weeks. Outcome assessments, including adherence to the weight loss diet and changes in anthropometric measures (fat-free mass (FFM), fat mass (FM), and body mass index), will be performed at baseline and 4, 8, and 12 weeks. Adherence will be assessed based on changes in FM and FFM to avoid reliance on self-reported data. Additional assessments will include scores from validated psychological and health-related questionnaires, including the Weight Self-Stigma Questionnaire, the Weight Bias Internalization Scale, and the General Health Questionnaire.

Discussion: This study aims to clarify its role in improving dietary adherence and weight management outcomes by addressing weight self-stigma through a CBT intervention. If successful, the findings could inform healthcare strategies and contribute to developing comprehensive interventions for obesity management. The study is expected to provide evidence for integrating psychological support into weight loss programs, particularly for populations most affected by stigma. We suggest that this trial has the potential to refine therapeutic approaches for weight management in women with obesity.

Trial registration: IRCT20140907019082N12 Registered on November 25, 2023.