Ngoc Minh Pham1, Akiko Nanri1, Kayo Kurotani1, Keisuke Kuwahara1, Ayami Kume1, Masao Sato2, Hitomi Hayabuchi3, Tetsuya Mizoue1. 1. 1 Department of Epidemiology and Prevention, Clinical Research Center, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 162-8655, Japan. 2. 2 Department of Applied Biological Chemistry, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan. 3. 3 Faculty of Human Environmental Science, Fukuoka Women's University, Fukuoka, Japan.
Abstract
OBJECTIVE: To examine the association between the consumption of green tea, coffee and caffeine and depressive symptoms. DESIGN: Cross-sectional study. Consumption of green tea and coffee was ascertained with a validated dietary questionnaire and the amount of caffeine intake was estimated from these beverages. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale. Multiple logistic regression analysis was performed to compute odds ratios and 95% confidence intervals for depressive symptoms with adjustments for potential confounders. SETTING: Two workplaces in north-eastern Kyushu, Japan, in 2009. SUBJECTS: A total of 537 men and women aged 20-68 years. RESULTS: Higher green tea consumption was associated with a lower prevalence of depressive symptoms. Compared with participants consuming ≤1 cup/d, those consuming ≥4 cups green tea/d had a 51% significantly lower prevalence odds of having depressive symptoms after adjustment for potential confounders, with significant trend association (P for trend = 0·01). Further adjustment for serum folate slightly attenuated the association. Coffee consumption was also inversely associated with depressive symptoms (≥2 cups/d v. <1 cup/d: OR = 0·61; 95% CI 0·38, 0·98). Multiple-adjusted odds for depressive symptoms comparing the highest with the lowest quartile of caffeine consumption was OR = 0·57 (95% CI 0·30, 1·05; P for trend = 0·02). CONCLUSIONS: Results suggest that higher consumption of green tea, coffee and caffeine may confer protection against depression.
OBJECTIVE: To examine the association between the consumption of green tea, coffee and caffeine and depressive symptoms. DESIGN: Cross-sectional study. Consumption of green tea and coffee was ascertained with a validated dietary questionnaire and the amount of caffeine intake was estimated from these beverages. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale. Multiple logistic regression analysis was performed to compute odds ratios and 95% confidence intervals for depressive symptoms with adjustments for potential confounders. SETTING: Two workplaces in north-eastern Kyushu, Japan, in 2009. SUBJECTS: A total of 537 men and women aged 20-68 years. RESULTS: Higher green tea consumption was associated with a lower prevalence of depressive symptoms. Compared with participants consuming ≤1 cup/d, those consuming ≥4 cups green tea/d had a 51% significantly lower prevalence odds of having depressive symptoms after adjustment for potential confounders, with significant trend association (P for trend = 0·01). Further adjustment for serum folate slightly attenuated the association. Coffee consumption was also inversely associated with depressive symptoms (≥2 cups/d v. <1 cup/d: OR = 0·61; 95% CI 0·38, 0·98). Multiple-adjusted odds for depressive symptoms comparing the highest with the lowest quartile of caffeine consumption was OR = 0·57 (95% CI 0·30, 1·05; P for trend = 0·02). CONCLUSIONS: Results suggest that higher consumption of green tea, coffee and caffeine may confer protection against depression.