Green tea consumption and risk of cardiovascular and ischemic related diseases: A meta-analysis.

Background: The effects of green tea intake on risk of cardiovascular disease (CVD) have not been well-defined. The aim of this meta-analysis was to evaluate the association between green tea consumption, CVD, and ischemic related diseases.

Methods: All observational studies and randomized trials that were published through October 2014 and that examined the association between green tea consumption and risk of cardiovascular and ischemic related diseases as the primary outcome were included in this meta-analysis. The quality of the included studies was evaluated according to the Cochrane Handbook 5.0.2 quality evaluation criteria.

Results: A total of 9 studies including 259,267 individuals were included in the meta-analysis. The results showed that those who didn't consume green tea had higher risks of CVD (OR=1.19, 95% CI: 1.09-1.29), intracerebral hemorrhage (OR=1.24, 95% CI: 1.03-1.49), and cerebral infarction (OR=1.15, 95% CI: 1.01-1.30) compared to <1 cup green tea per day. Those who drank 1-3 cups of green tea per day had a reduced risk of myocardial infarction (OR=0.81, 95% CI: 0.67-0.98) and stroke (OR=0.64, 95% CI: 0.47-0.86) compared to those who drank <1 cup/day. Similarly, those who drank ≥4 cups/day had a reduced risk of myocardial infarction compared to those who drank <1 cup/day (OR=0.68, 95% CI: 0.56-0.84). Those who consumed ≥10 cups/day of green tea were also shown to have lower LDL compared to the <3 cups/day group (MD=-0.90, 95% CI: -0.95 to -0.85).

Conclusions: Our meta-analysis provides evidence that consumption of green tea is associated with favorable outcomes with respect to risk of cardiovascular and ischemic related diseases.