title: Green tea consumption and hematologic malignancies in Japan: the Ohsaki study.
abstract: Several biologic studies have reported that green tea constituents have antitumor effects on hematologic malignancies. However, the effects in humans are uncertain. The authors used data from the Ohsaki National Health Insurance Cohort Study in Japan to evaluate the association between green tea consumption and the risk of hematologic malignancies. Study participants were 41,761 Japanese adults aged 40-79 years without a history of cancer at baseline who answered a food frequency questionnaire survey in 1994. During 9 years of follow-up beginning in 1995, the authors documented 157 hematologic malignancies, including 119 cases of lymphoid neoplasms and 36 cases of myeloid neoplasms. Hazard ratios were calculated by using the Cox proportional hazards regression model. Risk of hematologic malignancies was inversely associated with green tea consumption. The multivariate-adjusted hazard ratio of hematologic malignancies for 5 cups/day or more compared with less than 1 cup/day of green tea was 0.58 (95% confidence interval: 0.37, 0.89). The corresponding risk estimate was 0.52 (95% confidence interval: 0.31, 0.87) for lymphoid neoplasms and 0.76 (95% confidence interval: 0.32, 1.78) for myeloid neoplasms. This inverse association was consistent across sex and body mass index strata. In conclusion, green tea consumption was associated with a lower risk of hematologic malignancies.
authors.affiliation: Division of Epidemiology, Department of Public Health and Forensic Medicine, Tohoku University School of Medicine, Miyagi, Japan. a4mb1075-thk@umin.ac.jp
authors.forename: Toru
authors.initials: T
authors.lastname: Naganuma
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kuriyama
authors.forename: Masako
authors.initials: M
authors.lastname: Kakizaki
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Sone
authors.forename: Naoki
authors.initials: N
authors.lastname: Nakaya
authors.forename: Kaori
authors.initials: K
authors.lastname: Ohmori-Matsuda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hozawa
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Nishino
authors.forename: Ichiro
authors.initials: I
authors.lastname: Tsuji
mesh_terms: D000328:Adult; D000368:Aged; D002392:Catechin / Q000008:administration & dosage*; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D006306:Health Surveys; D019337:Hematologic Neoplasms / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D013030:Spain; D011795:Surveys and Questionnaires; D013662:Tea
chemical_list: D013662:Tea; D002392:Catechin