Associations of depression and intake of antioxidants and vitamin B complex: Results of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

Background: Optimum functioning of the central nervous system is dependent on a wide range of nutrients, so mental illness can be impacted by diet via several mechanisms. We aimed to investigate the associations of antioxidants (vitamin A, C and E, and selenium and zinc) and vitamin B complex (B6, folate and B12) intake with depression in 14,737 subjects of the Brazilian Longitudinal Study of Adult Health.

Methods: Baseline cross-sectional data was analyzed. Micronutrients intake was measured using the Food Frequency Questionnaire, and depression was assessed using the Clinical Interview Schedule Revised. Logistic regression models were built using daily intake quintiles of micronutrients.

Results: A significant inverse relationship was observed between depression and higher intake of selenium, zinc, vitamins B6 and B12 for the total sample. Among women, a similar pattern of associations was observed, in addition to the higher intake of vitamins A and C. Among men, a significant inverse relationship between depression was observed only with the intake of vitamins B12 and B6. Higher total antioxidant intake was significantly associated with lower odds of depression and an inverse dose-response effect between total antioxidant intake and clinical severity of depression was observed among women, in adjusted models.

Limitations: Recall bias in assessing diet. Misclassification bias regarding current depression.

Conclusions: Depression is associated with lower intake of antioxidants and B vitamins. Higher intake of selected micronutrients may contribute to reduce depression occurrence and severity.