Habitual tea consumption was associated with lower levels of depressive symptoms among older Chinese: Guangzhou Biobank Cohort Study

Abstract

Previous studies showed that some components in tea had potential beneficial effects on depression. However, population-based studies examining the potential benefits of tea on depression are limited. We hypothesized that older Chinese with habitual tea consumption had lower levels of depressive symptoms than those without habitual tea consumption. A cross-sectional analysis of baseline data from the Guangzhou Biobank Cohort Study was conducted. Depressive symptoms were measured by the 15-item Geriatric Depression Scale (GDS) score (continuous), with the presence defined by a GDS ≥ 8. Of 10,014 participants, 421 (4.20%) had depressive symptoms. After adjusting for potential confounders, compared with never-consumers, occasional and regular consumers had lower GDS scores (β [95% confidence interval]: -0.29 [-0.46, -0.11] and -0.60 [-0.78, -0.42], respectively), and regular consumers showed lower odds of depressive symptoms (odds ratio [95% CI]: 0.51 (0.35-0.72). In regular tea consumers, greater frequency, amount per occasion and per week, and higher amount-years showed lower GDS score (all P for trend <0.001) and lower odds of depressive symptoms (all P for trend < .05) than nonconsumers. The results were similar by different types of tea (green tea, black tea, and oolong tea) consumed. Further adjustment for social characteristics of tea consumption attenuated the association slightly but not fully. In conclusion, habitual tea consumption was associated with lower levels of depressive symptoms among older Chinese, which might be partly explained by social interaction during consumption. Further investigation on causation and mechanisms, including mechanistic randomized controlled trials is warranted.

Keywords: Consumed characteristics; Depressive symptoms; Older Chinese; Social interaction; Tea consumption.