The association between raw garlic consumption and the risk of depressive symptoms: the TCLSIH cohort study

Background: Garlic has antioxidant, anti-inflammatory, cardiovascular improvement and other beneficial effects on human health. However, few studies have evaluated the association of garlic intake with the risk of depressive symptoms. The aim of this prospective cohort was to examine the association between the frequency of raw garlic consumption and depressive symptoms in the general adult population. Methods: A total of 7427 participants (mean +/- standard deviation: 39.7 +/- 10.5 years) without baseline depressive symptoms were included in the cohort study. Garlic consumption was assessed using a validated food frequency questionnaire, and depressive symptoms were assessed by a Chinese version of the Self-rating Depression Scale score (SDS score >= 45). Multivariable Cox proportional hazards models were used to determine the association between garlic consumption and the risk of depressive symptoms. Results: This study identified 1070 cases of depressive symptoms during a median follow-up of 2.0 years, with a depression prevalence of 73.4 cases per 1000 person-years. After multivariate adjustment, the hazard ratios (95% confidence intervals) for depressive symptoms in males were 1.00 (reference) for almost never, 1.05 (0.84, 1.32) for <= 1 time per week, 1.16 (0.90, 1.49) for 2-3 times per week, and 1.31 (0.97, 1.78) for >= 4 times per week, and in females, they were 1.00 (reference) for almost never, 0.85 (0.69, 1.06) for <= 1 time per week, 0.72 (0.54, 0.97) for 2-3 times per week, and 0.78 (0.53, 1.13) for >= 4 times per week. Conclusion: In a large general population, we demonstrate for the first time that moderate raw garlic consumption is associated with a reduced risk of depressive symptoms in females, but not in males. Additional prospective studies with long-term follow-up and randomized controlled trials are necessary to confirm the preliminary results of the current study. Garlic has antioxidant, anti-inflammatory, cardiovascular improvement and other beneficial effects on human health. In a large general population, we demonstrate that moderate raw garlic consumption is associated with a reduced risk of depressive symptoms in females, but not in males.