Search resultsAlcohol consumption and breast cancer risk by family history of breast cancer and folate intake in younger women.
To evaluate the association between alcohol consumption and breast cancer risk in younger women, and by family history of breast cancer and folate intake, we prospectively followed 93,835 U.S. women aged 27-44 years with alcohol consumption data in 1991 in the Nurses' Health Study II. Alcohol and folate intake was measured by food frequency questionnaire repeated every 4 years. We documented 2,866 incident invasive breast cancer cases between 1991 and 2011. Alcohol consumption was not associated with breast cancer risk overall (multivariate hazard ratio = 1.07, 95% confidence interval: 0.94, 1.22 for ≥ 10 g/d intake vs. nondrinkers). When the association was stratified by family history and folate intake, a positive association between alcohol consumption and breast cancer was found among those with a family history and folate intake of < 400 μg/d (multivariate hazard ratio = 1.82; 95% confidence interval: 1.06, 3.12; P-trend = 0.08). Alcohol intake was not associated with breast cancer in other categories of family history and folate intake (P-interaction = 0.55). In conclusion, in this population of younger women, higher alcohol consumption was associated with increased risk of breast cancer among those with both family history of breast cancer and lower folate intake.