Adherence to a Mediterranean Diet Is Associated with Lower Depressive Symptoms among U.S. Adults

Depression is a leading cause of disability, yet current prevention and treatment approaches have only had modest effects. It is important to better understand the role of dietary patterns on depressive symptoms, which may help prevent depression or complement current treatments. This study examined whether adherence to a Mediterranean diet (Med Diet), determined by the Alternate Med Diet score (aMED), was associated with depressive symptoms in a representative sample of U.S. adults. The aMED score (range 0-9) was calculated from a 24-h diet recall with gender-specific quartiles (Q) estimated. The Patient Health Questionnaire-9 (PHQ-9) was used to define depressive symptoms, which was dichotomized as no to mild (0-9) versus moderate to severe symptoms (10-27). Logistic regression was used to investigate the association between quartiles of aMED and depressive symptoms when controlling for sociodemographics, total calories, and the time of year of diet recall; 7.9% of the sample had moderate to severe depressive symptoms. Compared to individuals with the lowest aMED (Q1), individuals in Q3 and Q4 had 40% and 45% lower odds of moderate to severe depressive symptoms (odds ratio [OR] = 0.60, 95% confidence interval [CI]: 0.50, 0.74; OR = 0.55, 95% CI: 0.36, 0.84, respectively). This study provides modest support of Med Diet's role in supporting positive mental health.