Could a glass of wine a night increase your cancer risk?

Could your happy hour beverages be increasing your cancer risk?

According to a recent study from the World Cancer Research Fund and the American Institute for Cancer Research, as little as 10 grams of alcohol per day—that’s a small glass of wine, 8 ounces of beer or a shot of a harder liquor—can increase your risk of breast cancer. The study determined that this seemingly minimal amount increases cancer in premenopausal women by 5% and postmenopausal women by 9%.

Dr. Anne McTiernan, the lead author of the report, told CNN, “I was most surprised by the alcohol result, that risk increases at just one drink a day, on average. The increase with one drink a day was small ... but the risk goes up from there.”

While the amount of alcohol that can have an impact may be surprising, doctors have long known the risk associated with drinking.

“Previous studies have shown that the risk of developing breast cancer increases as the number of drinks per day increases,” Robert Mocharnuk, MD, a specialist in hematology and oncology and director of The Breast Center at the Simmons Cancer Institute. “So the take-home message here is that if you drink on a daily basis, you increase the risk of developing breast cancer more than if you have an occasional drink on social occasions.”

Despite this concerning news, alcohol is not without its well-known benefits. But Dr. Mocharnuk stresses that one must decide for oneself if that glass is worth it.

“Alcohol has been shown to lower the risk of heart disease—a glass of red wine daily is the mantra—but this should serve as a cautionary tale that the benefits to one organ system may be outweighed by the risks to another organ system. If I were at risk for breast cancer, I would probably continue my current practice of having a drink on rare social occasions—maybe once or twice per month, if even that.”