Race/Ethnicity Moderates Associations between Depressive Symptoms and Diet Composition among U.S. Adults

Abstract

Objective: 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.