Just a few drinks a week tied to breast cancer

Women who drink just a few glasses of wine or beer a week may have a slightly increased breast cancer risk, researchers said Tuesday.

Their findings are based on more than 100,000 nurses followed over three decades and add weight to earlier studies linking alcohol to breast cancer and other tumors.

"Even at low levels of alcohol consumption, three to six drinks per week, we found a modest increase in risk," said Dr. Wendy Chen of Brigham and Women's Hospital in Boston, whose findings appear in the Journal of the American Medical Association.

And, she added, "There wasn't a particular period in which it was safe to drink alcohol."

But before you put away the Pinot, there are some important caveats to consider.

First, it wasn't a huge effect - about 15 percent higher risk among drinkers compared with teetotalers. For example, even among women who sipped three to six glasses of wine per week, only 3.3 percent would develop breast cancer over 10 years. That compares to 2.8 percent of abstainers and 3.5 percent of women having up to 13 drinks a week.

The Relationship between Wine and Breast Cancer There has been a cloud of inconsistencies and controversy surrounding the association between moderate wine consumption and Breast Cancer. The one consistent conclusion is that drinking 3 or more drinks per day significantly increases your risk of getting Breast Cancer.

In 1997, a study by Dr. Thun et. al. from the American Cancer Society and Epidemiology Unit at Oxford indicated the benefit of moderate alcohol consumption. They showed that women who were moderate drinkers (one drink per day) had a lower death rate than non-drinkers. The results were statistically significant, with a 21% reduction, but the majority of the benefit came from cardiovascular disease.

However, recently published information is not as favorable with respect to breast cancer. Dr. Smith-Warner et. al. from Harvard studied the association between alcohol consumption and Breast Cancer. Their results showed a linear increase in breast cancer over a wide range of consumption. This group of researchers is highly regarded in the medical research field, and their results are widely accepted. Overall, they concluded that for every 10 grams of alcohol ingested daily, there was a 9% increase in Breast Cancer risk.

There have been other studies that have examined this relationship with mixed results. The only constant seems to be with alcohol consumption over 3 drinks per day, which increases Breast Cancer risk dramatically.

Second, there is still no ironclad proof that alcohol itself is to blame, even though the researchers did their best to rule out competing explanations such as smoking or older age. They also adjusted for other influences on breast cancer risk, like whether or not a woman has had children and breastfed.