In this issue of JAMA, Chen and colleagues1 report findings from the Nurses' Health Study exploring the relationship between alcohol consumption and breast cancer risk. The authors' principal findings were that the cumulative amount of alcohol a woman consumes during adulthood is the best predictor of her breast cancer risk and that low levels of alcohol consumption (as few as 3 drinks a week) are associated with an increased risk of breast cancer. In addition, the risk of breast cancer was increased with the quantity consumed; for example, women who drank 2 or more drinks per day had a risk of breast cancer approximately 1.5 times higher than women who never consumed alcohol, and their 10-year risk of breast cancer increased by 1.3% (from 2.8% to 4.1%). For women who drank 1 drink per day, the risk was approximately 1.2 times higher than expected and their 10-year risk increased by 0.7% (from 2.8% to 3.5%).
Narod SA. Alcohol and Risk of Breast Cancer. JAMA. 2011;306(17):1920–1921. doi:10.1001/jama.2011.1589