Are dietary patterns associated with depression in U.S. Adults?

Nutrition is one of the most important modifiable determinants for and consequences of both mental and physical heath. Depression has become an increasingly important public health issue. We tested whether dietary patterns derived from food group intake are associated with depression in U.S. adults in a cross-sectional study with national population. This study included 4180 men and 4196 women aged 20-79 years in the 2007-2010 National Health and Nutrition Examination Surveys (NHANES), with complete data of one 24-h dietary recall, sociodemographics, lifestyles, and Patient Health Questionnaires (PHQ-9) for screening depression. Two major dietary patterns identified by factor analysis were investigated for their associations with presence of depression (PHQ-9 score ≥10) by using linear and multivariate logistic regressions. One of two major patterns, labeled "Western" dietary pattern was characterized by high intakes of nonwhole grain, white potatoes, cheese, meat, discretionary oil and fat, and added sugar; the second dietary pattern that was labeled "Healthy" dietary pattern was characterized by high intakes of whole grains, vegetables, fruits, fish, nuts and seeds. The "Western" dietary pattern was not significantly associated with depression in both men and women. The "Healthy" dietary pattern scores were inversely associated with the PHQ-9 depression scores and odd ratios (ORs) of depression after adjustment for covariates in women but not in men. The OR of depression in women with the highest quintile of "Healthy" dietary pattern scores was 0.60 (95% confidence interval [CI]: 0.42-0.85, P < .001) compared to the lowest quintile as a reference. These findings warrant future interventions or clinical trials in elucidating causal and effect relations of depression and dietary patterns, an important public health concern.