Environment and Breast Cancer: Science Review

A prospective study of green tea consumption and cancer incidence, Hiroshima and Nagasaki (Japan)
Nagano, J., Kono, S., Preston, D. L., Mabuchi, K. Cancer Causes Control. 2001. 12:6, 501-8.

Topic area
Diet
Diet
Study design
Prospective cohort
Prospective cohort

Study Participants
Number of Cases
276
276
Menopausal Status
The menopausal status of women included in this study is listed here.
Postmenopausal and premenopausal combined
Number of Controls
23,667
23,667
Cohort participation rate
Not reported
Not reported
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: Women in the Life span study who responded to a mail survey between 1979 - 1981 Ex: Maligant neoplasm before the start of diagnosis
Comment about participation selection
Limited information on diet - only 22 item questionnaire
Limited information on diet - only 22 item questionnaire

Exposure Investigated
Exposures investigated
Green tea
Green tea
How exposure was measured
Questionnaire, self-administered, 22 dietary items only
Questionnaire, self-administered, 22 dietary items only
Exposure assessment comment
Limited information on diet - only 22 item questionnaire
Limited information on diet - only 22 item questionnaire

Statistical Analysis
Breast cancer outcome investigated
Primary breast cancer
Primary breast cancer
Ethnic groups with separate analysis
If this study provided a separate analysis by ethnic or racial group, the groups are listed here.
None
Confounders considered
Other breast cancer risk factors, such as family history, age at first birth, and hormone replacement therapy use, that were taken into account in the study.
Not considered: Parity, menopausal status, family history of breast cancer, race
Genetic characterization included
If the study analyzed relationships between environmental factors and inherited genetic variations, this field will be marked “Yes.” “No”, if not.
No
Description of major analysis
Adjusted RR with 95% CI, highest vs. lowest tertile, follow-up 1981 - 1994
Adjusted RR with 95% CI, highest vs. lowest tertile, follow-up 1981 - 1994
Strength of associations reported
1.0 (0.67 - 1.6)
1.0 (0.67 - 1.6)
Results Comments
Failed to find a clear, protective association between green tea consumption and the incidence of cancers.
Failed to find a clear, protective association between green tea consumption and the incidence of cancers.

Author address
Department of Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan. nagano@rer.or.jp
Department of Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan. nagano@rer.or.jp