Abstract
BACKGROUND: Some studies have reported associations between self-esteem and weight status, but longitudinal data on adults remain scarce. The aim of this population-based study was to analyze the cross-sectional and longitudinal association between self-esteem and body mass index (BMI) and to investigate whether baseline BMI has an impact on this association. METHODS: In 2016, 29,735 participants aged ≥ 18 years in the NutriNet-Santé cohort completed the Rosenberg Self-Esteem Scale. BMI was self-reported yearly over a 4-year period. Association between self-esteem and BMI was assessed using mixed models and logistic regressions. Analyses were stratified by BMI (categorical) at baseline and adjusted on sociodemographic and lifestyle characteristics. RESULTS: At baseline, higher self-esteem was associated with higher BMI in normal weight individuals(p = 0.32), and with lower BMI in obese class II and III individuals (p = 0.13). In addition, higher baseline self-esteem was associated with BMI increase over time in normal weight individuals (p = 0.15). Among normal weight individuals, those with higher self-esteem were less likely to show a decrease in their BMI (p = 0.005), while no association was observed with BMI increase (p = 0.81). DISCUSSION: Our findings suggest that the association between self-esteem and BMI depends on the initial category of BMI, with a negligible effect of self-esteem.