Trait disinhibition mediates the associations of depressive symptoms and BMI in a non-clinical cohort of lean and individuals with obesity

Background Depressive symptoms affect eating behavior and body mass index (BMI). We investigated their relationship in a non-clinical cohort without depressive or eating disorders and explored whether trait eating behavior mediates the association between depressive symptoms and BMI. Methods Seventy-seven participants (62.3% women, aged 20–69 years) from the Obese Taste Bud study, with varying weight status and no depressive or eating disorders, completed the General Depression Scale (GDS), Three-Factor Eating Questionnaire (TFEQ), and Food Craving Questionnaire. Multiple linear regression analyses were conducted to examine the associations of depressive symptoms with trait eating behavior and BMI. Mediation analyses were performed using Hayes’ PROCESS macro in the Statistical Package for Social Sciences (SPSS). Results Higher depressive symptom scores predicted greater trait disinhibition ( β = 0.228, p = 0.044), emotional eating ( β = 0.307, p = 0.009), and food craving ( β = 0.309, p = 0.009) but not trait hunger, restraint eating, or cognitive restraint (all p < 0.05). Furthermore, higher depressive symptom scores predicted higher BMI ( β = 0.399, p < 0.001). Greater trait disinhibition ( β = 0.377, p < 0.001) and food craving ( β = 0.335, p = 0.002) were associated with a higher BMI. Trait disinhibition partially mediated the relationship between depressive symptoms and BMI (indirect effect: B = 0.0948, standard error [SE] = 0.0575; 95% confidence interval [CI]: 0.0022, 0.2250). Conclusion In non-clinical cohorts, depressive symptoms that do not meet the criteria for depressive disorders meaningfully influence stable patterns of unfavorable eating behaviors and body weight. Trait disinhibition was identified as a mediator linking depressive symptoms and BMI, highlighting a potential behavioral mechanism through which depressive symptoms may contribute to obesity.