Past research has shown that moderate alcohol consumption is associated with a modest increase in the risk for breast cancer. The risk associated with low level alcohol consumption and long time drinking patterns has not really been determined. In this current report, investigators analyzed data from the Nurses’ Health study, from 1980 to 2008. More than 74,000 nurses provided seven updates about their alcohol consumption and during this time period, 7690 cases of invasive breast cancer were diagnosed.
After adjusting for other breast cancer risk factors such as estrogen replacement therapy, it was determined that even low levels of alcohol at 3-6 glasses of wine per week, were associated with a small but significant elevated relative risk for breast cancer (1.15). The relative risk was higher in women who consumed two or more drinks per day (1.51). There was no difference in aged groups of 18-40 or > 40 or as to whether the alcohol was beer, wine, or liquor.
Commentary: It is fairly common knowledge that 7 drinks per week or more increase the risk of breast cancer. This new research is now pointing out that even lower amounts of alcohol, 3-6 per week, are associated with an increase risk, although considered a slight or modest increase. This advice has made it into my clinical practice and I encourage all women, and especially breast cancer survivors, to reduce their alcohol to none or less than 3 per week. What about the cardiovascular benefits of alcohol you might ask? My response is that we don’t actually have that many proven tools to lower our risk of breast cancer, but we do however have many known strategies to lower our risk of cardiovascular disease—, let alone several strategies or associations that have been shown at least in some research, to lower the risk of both including, weight management, high fiber diets, moderate exercise most days of the week, green tea, fish/fish oils and vitamin D. For now, my advice is to lower our alcohol to less than 3 drinks per week.
Chen W, et al. Moderate alcohol consumption during adult life, drinking patterns, and breast cancer risk. JAMA 2011; 2(306):1884.