Green tea consumption and mortality in Japanese men and women: a pooled analysis of eight population-based cohort studies in Japan
The aim of our study was to assess the association between green tea consumption and all-cause and cause-specific mortality in a pooled analysis of eight Japanese population-based cohort studies. Pooled hazard ratios (HR) and 95% confidence intervals (CI), derived from random effects models, were used to evaluate the associations between green tea consumption, based on self-report at baseline, and risk of all-cause and cause-specific mortality. During a mean follow-up of 17.3 years, among 313,381 persons, 52,943 deaths occurred. Compared with individuals who consumed < 1 cup/day, those in the highest consumption category (≥ 5 cups/day) had a decreased risk of all-cause mortality [the multivariate-adjusted HR was 0.90 (95% CI 0.87–0.94) for men and 0.82 (0.74–0.90) for women]. A similar inverse association was observed for heart disease mortality [HR 0.82 (0.75–0.90) for men, and 0.75 (0.68–0.84) for women], and cerebrovascular disease mortality [HR 0.76 (0.68–0.85) for men, and 0.78 (0.68–0.89) for women]. Among women, green tea consumption was associated with decreased risk of total cancer mortality: 0.89 (0.83–0.96) for the 1–2 cups/day category and 0.91 (0.85–0.98) for the 3–4 cups/day category. Results for respiratory disease mortality were [HR 0.75 (0.61–0.94)] among 3–4 cup daily consumers and [HR 0.66 (0.55–0.79)] for ≥ 5 cups/day. Higher consumption of green tea is associated with lower risk for all-cause mortality in Japanese, especially for heart and cerebrovascular disease. Moderate consumption decreased the risk of total cancer and respiratory disease mortality in women.
KeywordsGreen tea Mortality Cohort study Pooled analysis Japan
The Japan Public Health Center-based Prospective Study, Cohort I
The Japan Public Health Center-based Prospective Study, Cohort II
The Japan Collaborative Cohort Study
The Miyagi Cohort Study
The Ohsaki National Health Insurance Cohort Study
- 3-pref MIYAGI
The Three Prefecture Study—Miyagi portion
- 3-pref AICHI
The Three Prefecture Study—Aichi portion
- 3-pref OSAKA
The Three Prefecture Study—Osaka portion
MI designed the research. SKA performed the analyses, prepared the tables and drafted the paper. MI, ES, NS, ST, YL, and AS supported analyses, discussions and finalizing of the paper. HI, YL, AT, JS, YK, YS, IT, CN, TS, TM, KM, MN, and KT provided valuable feedback regarding interpretation of the results. All authors read and approved the final manuscript.
This study was supported by the National Cancer Center Research and Development Funds (30-A-15, 27-A-4, 24-A-3) and the Health and Labour Sciences Research Grants for the Third Term Comprehensive Control Research for Cancer (H21-3jigan-ippan-003, H18-3jigan-ippan-001, H16-3jigan-010). The funders had no role in the design, data collection, analysis, interpretation or manuscript drafting, or in the decision to submit the manuscript for publication.
Compliance with ethical standards
Conflict of interest
The authors have no potential conflicts of interests.
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