Association between Serum Vitamin Levels and Depression in U.S. Adults 20 Years or Older Based on National Health and Nutrition Examination Survey 2005–2006

Depression is one of the leading causes of disability around the world. Although several studies have been conducted to analyze the association between vitamins and depression, the results have been inconsistent. Based on the database of National Health and Nutrition Examination Survey (NHANES) (2005–2006), a cross-sectional analysis was conducted to uncover the correlations between serum vitamin concentrations and depression in 2791 participants over 20 years of age. Vitamin concentrations in serum were measured by high performance liquid chromatography (HPLC), a standardized liquid chromatography-tandem mass spectrometry (LC-MS/MS) or radioassay kit method. A nine-item Patient Health Questionnaire (PHQ-9) was used to assess depression symptoms. The binary logistic regression model was applied to analyze the association between vitamins and depression. In the whole population, negative associations were discovered between folate concentrations (p for trend = 0.02), trans-β-carotene (p for trend = 0.01) and depression, while positive associations were found among vitamin B12 concentrations (p for trend = 0.008), vitamin A concentrations (p for trend = 0.01) and depression. In order to evaluate the influence of gender on the pathogenesis of depression of vitamins exposure, we performed gender-stratified analysis. In females, folate concentrations (p for trend = 0.03) and vitamin B12 concentrations (p for trend = 0.02) were correlated with depression. In males, no significant association was found between depression and serum vitamin concentrations. The correlation of vitamins with depression deserves further investigation in larger and diverse populations, especially in females.