Vitamin D and Breast Cancer.
Abstract
Few epidemiologic studies to date have addressed the hypothesis that Vitamin D reduces breast cancer risk. We analyzed interview data obtained from a cohort of white women aged 25-74 years who participated in the first National Health and Nutrition Examination Survey (NHANES I) from 1971 to 1975 and were followed until 1987. We performed Cox proportional hazards analysis to assess the relationship between sunlight exposure, dietary vitamin D intake, and supplement use and breast cancer risk. The analytic cohort comprised 133 women diagnosed with breast cancer during follow-up and 4,748 women without a self-reported history of breast cancer. Reduced breast cancer risk was associated with high sunlight exposure assessed by the examining physician (RR=0.60, 95% Cl =0.33-1.09) and self-report (RR=0.54, 95% Cl =0.28-1.02), high solar radiation in state of longest residence (RR=0.59, 95% Cl =0.36-0.94), residence in the South at baseline (RR=0.59, 95% Cl =0.35-0.98), and dietary intake of more than 206 IU assessed by 24-hour dietary recall (RR=0.67, 95% Cl=0.40-1.11). Actinic skin damage, an indirect measure of sunlight exposure, and regular use of multivitamins were not associated with breast cancer risk. Adjustment for other risk factors only minimally changed the relative risk estimates. These findings support the hypothesis that vitamin D may reduce breast cancer risk and warrant future epidemiologic studies.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1996
- Accession Number
- ADA315677
Entities
People
- Esther M. John
- Jennifer L. Kelsey
Organizations
- Stanford University