Consumption of low-fat dairy, but not whole-fat dairy, is inversely associated with depressive symptoms in Japanese adults

Purpose Dairy products have been reported to have various beneficial effects on human health. Although some previous studies have shown relationships between dairy consumption and depressive symptoms, the results of these studies were not consistent. This study aimed to investigate the association between frequency of low- and whole-fat dairy consumption, and depressive symptoms. Methods This cross-sectional study enrolled 1159 Japanese adults aged 19–83 years. Dietary intake was assessed using a brief self-administered diet history questionnaire. Depressive symptoms were evaluated by a self-rating depression scale (SDS) (the presence of depressive symptoms was defined as an SDS score ≥45 points). Logistic regression models were used to analyze the association between the frequency of low- and whole-fat dairy consumption and depressive symptoms. Results Higher frequency of low-fat dairy consumption was associated with a lower prevalence of depressive symptoms. In the final adjusted model, the odds ratios and 95% confidence intervals for prevalence of depressive symptoms when no consumption of low-fat dairy was compared to moderate (1–3 times per week) and high (≥4 times/week) frequencies of low-fat dairy consumption were 0.96 (0.71, 1.30) and 0.51 (0.35, 0.77), respectively ( p for the trend = 0.004). No relationships were observed between the consumption of whole-fat dairy and depressive symptoms. Conclusions The current results indicate that a higher frequency of low-fat dairy consumption may be associated with a lower prevalence of depressive symptoms.