Thursday, 28 May 2015
Green tea consumption found to reduce deaths in both men and women
A prospective study initiated in 1994 in Japan involving 40,530 adults, aged 40-79 years. The subjects did not have stroke, coronary heart disease, or cancer at baseline. They were followed for 11 years for deaths due to all causes and for seven years for cause-specific mortality. Researchers observed an inverse relationship between green tea consumption and deaths due to cardiovascular disease and other causes in both men and women. However, no such association was found for decrease in the number of deaths due to cancer.
Although the sample size of the study is large, the number of cardiovascular disease and cancer cases was small therefore, the statistical power may not be sufficient. Other limitations of the study include patients lost to follow-up and obtaining data from self-administered questionnaires that may not be accurate. Therefore, well-designed clinical trials are needed to confirm the protective effects of green tea.
Kuriyama S, Shimazu T, Ohmori K, et al. Green tea consumption and mortality due to cardiovascular disease, cancer, and all causes in Japan: the Ohsaki study. JAMA. 2006;296(10):1255-65.