The association between emotional eating and depressive symptoms: a population-based twin study in Sri Lanka

This study investigated the genetic and environmental contributions to emotional overeating (EOE) and depressive symptoms, and their covariation, in a Sri-Lankan population, using genetic model-fitting analysis. In total, 3957 twins and singletons in the Colombo Twin and Singleton Study-Phase 2 rated their EOE behaviour and depressive symptoms, which were significantly associated (men: r = 0.11, 95% confidence interval (CI) 0.06-0.16, women: r = 0.12, 95% CI 0.07-0.16). Non-shared environmental factors explained the majority of variance in men (EOE e² = 87%, 95% CI 78-95%; depressive symptoms e² = 72%, 95% CI 61-83%) and women (EOE e² = 76%, 95% CI 68-83%; depressive symptoms e² = 64%, 95% CI 55-74%). Genetic factors were more important for EOE in women (h² = 21%, 95% CI 4-32%) than men (h² = 9%, 95% CI 0-20%). Shared-environmental factors were more important for depressive symptoms in men (c² = 25%, 95% CI 10-36%) than women (c² = 9%, 95% CI 0-35%). Non-shared environmental factors explained the overlap between depressive symptoms and EOE in women but not in men. Results differed from high-income populations, highlighting the need for behavioural genetic research in global populations.