Last week's report that drinking red wine could reduce the risk for breast cancer was just the latest in a long string of studies on the issue.
This week many middle-aged women experienced joy, and maybe even raised a glass, upon reading that red wine might stave off breast cancer. The study, published in the Journal of Women's Health, turns out to be quite small. It's a limited analysis of hormone levels in the blood of 36 premenopausal women who drank red and white wine for one month. Still, the story garnered headlines and enthusiastic posts, as if women wanted this news to be true.
For years now, we -- women who've had breast cancer and fear its recurrence, or who are simply at risk, or who are in the throes of it, still -- have been pummeled by reports about what we should and shouldn't eat or drink or do. A friend who's had breast cancer complains she can't have a glass of wine without her husband glancing over her shoulder. At family gatherings her father looks her way, sternly, if she sips from a tall stemmed glass. One woman I know attends fewer parties lately, tired of saying "no, thanks" to cocktails or champagne that otherwise flows freely.
You can't ethically test the premise that a carcinogen is harmful by giving it to some women and not others.
Some find it easier to stay home, avoiding temptation entirely. This pattern of behavior can compound a breast cancer patient's sense of social isolation, depression, and feelings of inadequacy. The question at hand is whether alcohol really does cause breast cancer in some cases and, for women who've had the disease, if partaking promotes its recurrence.
The issue's been out there -- on our minds, and, for some, tempering behavior -- for some time. In 1998, the French-based, WHO-affiliated IARC reviewed four prospective clinical trials, along with other data, and confirmed a link between alcohol consumption and breast cancer in women. Still, those authors cautioned: "a firm conclusion about a causal relationship cannot be made at present." The evidence supported a correlation, but nothing more definitive.
In November 2011, the Journal of the American Medical Association published findings from the Nurses' Health Study. This large analysis involved over 105,000 women monitored from 1980 until 2008. The investigators found that even moderate alcohol consumption -- as few as three drinks per week -- was associated with a statistically significant, slight increase in breast cancer rates. What's more, the study revealed an apparent dose-response, adding credibility to the carcinogen hypothesis. The more a woman drank over the course of 20 years, the more likely she was to develop breast cancer.
The author of an accompanying editorial, Dr. Steven Narod, referred to alcohol as a "third breast carcinogen." Alcohol followed on his short list only after ionizing radiation and hormone therapy. Still, he avoided absolutisms, advising: "For some women the increase in risk of breast cancer may be considered substantial enough that cessation would seem prudent. However, there are no data to provide assurance that giving up alcohol will reduce breast cancer risk."
In December 2011, an expert panel convened by the Institute of Medicine issued a detailed report on non-inherited, i.e. environmental, causes of breast cancer. There too, alcohol is presented as a clear culprit. A table of opportunities for women to reduce their breast cancer risk includes that women "limit or eliminate alcohol consumption." This comes amidst other ideas for healthy behavior, like avoiding unnecessary radiation, not smoking, exercising more, and not being too heavy, as I have considered elsewhere.