Green Tea Consumption and Mortality among Japanese Elderly People: The Prospective Shizuoka Elderly Cohort
Author: Etsuji Suzuki and Takashi Yorifuji and Soshi Takao and Hirokazu Komatsu and Masumi Sugiyama and Toshiki Ohta and Kazuko Ishikawa-Takata and Hiroyuki Doi
Purpose To investigate the association between green tea consumption and mortality from all causes, cancer, and cardiovascular disease (CVD) among elderly people. Methods In a population-based, prospective cohort study, a total of 14,001 elderly residents (aged 65–84 years), randomly chosen from all 74 municipalities in Shizuoka, Japan, completed questionnaires that included items about frequency of green tea consumption. They were followed for up to 6 years, from December 1999 to March 2006. Consequently, 12,251 subjects were analyzed to estimate the hazard ratios (HRs) for all-cause mortality, cancer, and CVD. Results Among 64,002 person-years, 1,224 deaths were identified (follow-up rate, 71.6%). The multivariate HRs and 95% confidence intervals (CIs) for CVD mortality compared those who consumed seven or more cups per day with those who consumed less than one cup per day, were 0.24 (0.14–0.40), 0.30 (0.15–0.61), and 0.18 (0.08–0.40) for total participants, men, and women, respectively. Although green tea consumption was not inversely associated with cancer mortality, green tea consumption and colorectal cancer mortality were inversely associated with a moderate dose-response relationship. Conclusions Green tea consumption is associated with reduced mortality from all causes and CVD. This study also suggests that green tea could have protective effects against colorectal cancer.