Green tea consumption and the risk of stroke: A systematic review and meta-analysis of cohort studies

Wang ZM, Chen B, Zhou B, Zhao D, Wang LS · Nutrition · 2023 March

DOI 10.1016/j.nut.2022.111936

Objective

Epidemiologic studies are inconsistent regarding the association between green tea consumption and the risk of stroke. We performed a meta-analysis to determine whether an association exists between them in cohort studies.

Conclusions

This meta-analysis suggests that green tea consumption is inversely associated with the risk of stroke, especially among those with moderate consumption. Our results support recommendations for green tea consumption to the primary prevention of stroke.

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Insights

Our dose-response analysis indicated that moderate green tea consumption (500–1000 mL/d) was associated with a 21% to 24% lower risk of stroke.

The meta-analysis aimed to clarify the inconsistent findings in epidemiologic studies regarding the link between green tea consumption and stroke risk. Five prospective cohort studies, involving 645,393 participants and 11,421 stroke cases, were analyzed. The summary relative risk (RR) revealed a substantial association, indicating a 26% reduction in stroke risk with the highest green tea consumption. The dose-response analysis indicated a nonlinear relationship, and compared with non-consumers, various levels of green tea intake showed progressively reduced RRs for stroke, emphasizing a potential protective effect. The findings from the meta-analysis strongly suggest an inverse association between green tea consumption and stroke risk. Notably, the highest green tea consumption demonstrated a significant 26% risk reduction. The dose-response analysis further highlighted a nonlinear relationship, with moderate consumption levels (500–1000 mL/d) showing the most substantial risk reduction. These results provide support for recommending green tea consumption as a measure for the primary prevention of stroke.