Environment and Breast Cancer: Science Review

Milk consumption and cancer incidence: a Norwegian prospective study
Ursin, G., Bjelke, E., Heuch, I., Vollset, S. E. Br J Cancer. 1990. 61:3, 456-9.

Topic area
Diet
Diet
Study design
Prospective cohort
Prospective cohort
Funding agency
NCI; Norwegian Cancer Society
NCI; Norwegian Cancer Society

Study Participants
Menopausal Status
Pre menopausal
The menopausal status of women included in this study is listed here.
Post menopausalPre menopausal
Number in Cohort
Cohort 2679
Cohort 2679
Cohort participation rate
More than 70%
More than 70%
Participant selection: Inclusion and exclusion criteria
Criteria used to select participants in the study.
In: spouse and siblings of individuals interviewed in a Norwegian case-control study of gastro-intestinal cancer. Parent study exists, but not cited.
Comment about participation selection
Small cohort, not specific to breast cancer
Small cohort, not specific to breast cancer

Exposure Investigated
How exposure was measured
Questionnaire, self-administered
Questionnaire, self-administered
Exposure assessment comment
Limited information on the questionnaire, no question on type of milk
Limited information on the questionnaire, no question on type of milk

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: BMI, parity, menopausal status, alcohol consumption, race, family history of breast cancer
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
Age adjusted OR with two sided p value for trend, more than 2 glasses/day versus less than 1 glass/day, follow up 11.5 years
Age adjusted OR with two sided p value for trend, more than 2 glasses/day versus less than 1 glass/day, follow up 11.5 years
Strength of associations reported
1.48 (p-value for trend: 0.4)
1.48 (p-value for trend: 0.4)
Results Comments
Weak positive association between milk consumption and risk of breast cancer.
Weak positive association between milk consumption and risk of breast cancer.

Author address
Centre for Epidemiologic Research, University of Bergen HIB, Norway.
Centre for Epidemiologic Research, University of Bergen HIB, Norway.