Race/Ethnicity Moderates Associations Between Depressive Symptoms and Diet Composition Among U.S. Adults

Although depression is associated with poorer overall diet quality, few studies have examined its association with levels of particular macronutrients, and none have examined moderation by race/ethnicity. The present study examined (a) associations between depressive symptom severity and nine indices of diet composition and (b) whether race/ethnicity moderates these associations. Method:Participants were 28,940 adults (mean age = 49 years, 52% female, 52% nonwhite) from NHANES 2005–2018. Depressive symptom severity was measured using the Patient Health Questionnaire-9 (PHQ-9). Nine diet composition indices were derived from the average of two 24-hr dietary recalls(e.g., total energy, total fat, saturated fat, total carbohydrate, sugar, fiber, and protein). Results: Separate linear regression analyses revealed that PHQ-9 total was positively associated with saturated fat and sugar and negatively associated with protein and fiber. Moderation by race/ethnicity was observed(interaction ps,.05). Among non-Hispanic Whites, PHQ-9 total was positively associated with sugar and negatively associated with protein and fiber. Among non-Hispanic Blacks, PHQ-9 total was positively associated with total energy, total fat, saturated fat, monounsaturated fat, polyunsaturated fat, total carbohydrate, and sugar. Among Mexican Americans, PHQ-9 was positively associated with saturated fat. Among other Hispanics, PHQ-9 total was negatively associated with fiber, protein, and total, monounsaturated, and polyunsaturated fat. Conclusions: Findings from this large, nationally representative sample demonstrate that associations between depressive symptom severity and diet composition vary by race/ethnicity. Critically, an unhealthy diet composition pattern may be one mechanism explaining the excess risk of obesity and cardiometabolic diseases in individuals with depression, especially in non-Hispanic Blacks.