Environment and Breast Cancer: Science Review

Dietary carbohydrates, fiber, and breast cancer risk
Holmes, M. D., Liu, S., Hankinson, S. E., Colditz, G. A., Hunter, D. J., Willett, W. C. Am J Epidemiol. 2004. 159:8, 732-9.

Topic area
Diet
Diet
Study design
Prospective cohort
Prospective cohort
Funding agency
NIH
NIH

Study Participants
Number of Cases
4,092
4,092
Menopausal Status
The menopausal status of women included in this study is listed here.
Post menopausal and premenopausal separate
Number in Cohort
Cohort 88,678
Cohort 88,678
Cohort participation rate
Not reported
Not reported
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: Registered nurses from across the United States, participating in the NHS I, who answered a mailed questionnaire and were between 30-55 years in 1976, and also answered a diet questionnaire in 1980.
Ex: Dietary information was incomplete, if their total energy intake was implausible, had been diagnosed with cancer other than non-melanoma skin cancer.
Comment about participation selection
Long follow-up (18 years), 5 dietary assessments of the same participants
Long follow-up (18 years), 5 dietary assessments of the same participants
Exposures investigated
Carbohydrates (CH), Glycemic Load (GL), Glycemic index (GI)
Carbohydrates (CH), Glycemic Load (GL), Glycemic index (GI)
How exposure was measured
Questionnaire, self-administered, FFQ
Questionnaire, self-administered, FFQ

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.
No
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: 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, higher versus lower quintile of intake, stratified by menopausal status at the time of diagnosis, by BMI and physical activity. Follow-up 18 years
Adjusted RR with 95% CI, higher versus lower quintile of intake, stratified by menopausal status at the time of diagnosis, by BMI and physical activity. Follow-up 18 years
Strength of associations reported
CH: 0.97 (0.87-1.08); GI: 1.08 (0.97-1.19); GL: 0.99 (0.89-1.10)
Premenopausal: CH: 0.98(0.78-1.23); GI:1.02(0.82-1.28); GL:0.87(0.0-1.12)
Postmenopausal: CH:0.96 (0.84-1.09); GI:1.15(1.02-1.30); GL:1.03(0.90-1.16)
CH: 0.97 (0.87-1.08); GI: 1.08 (0.97-1.19); GL: 0.99 (0.89-1.10)
Premenopausal: CH: 0.98(0.78-1.23); GI:1.02(0.82-1.28); GL:0.87(0.0-1.12)
Postmenopausal: CH:0.96 (0.84-1.09); GI:1.15(1.02-1.30); GL:1.03(0.90-1.16)
Results Comments
No significant overall association between intake of carbohydrates, dietary glycemic index and glycemic load and risk of incident breast cancer across all menopausal categories.
No significant overall association between intake of carbohydrates, dietary glycemic index and glycemic load and risk of incident breast cancer across all menopausal categories.

Author address
Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. michelle.holmes@channing.harvard.edu
Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. michelle.holmes@channing.harvard.edu