Washington State University, Richland, WA 99352, USA. cshipowick@charter.net
BACKGROUND: Research indicates that vitamin D supplementation may decrease depressive symptoms during the winter months. METHOD: In this study, nine women with serum vitamin D levels <40 ng/ml were administered the Beck Depression Inventory (BDI)-II. After vitamin D3 supplementation, six of these women completed the BDI-II and had their serum vitamin D levels reassessed. RESULTS: Vitamin D supplementation was associated not only with an increase in the serum D levels by an average of 27 ng/ml but also with a decline in the BDI-II scores of an average of 10 points. DISCUSSION: This study suggests that supplemental vitamin D3 reduces depressive symptoms.