Women who enjoy beer or wine may want to reconsider ordering a second round – or even their first one – the next time they're at the bar, according to a new report which found that a small alcoholic beverage is all it takes to raise the risk of breast cancer.
The report from the World Cancer Research Fund and the American Institute for Cancer Research, released Tuesday, found that drinking just 10 grams of alcohol per day – equivalent to one small glass of wine, an 8oz beer, or 1oz of hard liquor – raises the risk of breast cancer.
The increased risk was more profound in postmenopausal women (9 percent increase) than in premenopausal women (5 percent increase).
However, any risk posed by just 10 grams of alcohol is big news, as the average alcoholic beverage (like a 12oz beer can) typically contains around 14 grams.
The report is part of the Continuous Update Project (CUP), which analyzes global cancer prevention and survival research by studying links between cancer and diet, nutrition, physical activity, and weight.
The Tuesday report is based on the evaluation of 119 studies which include data on 12 million women from across the globe. It is the first study of its kind since 2010.
"I was most surprised by the alcohol result, that risk increases at just one drink a day on average," lead study researcher Dr. Anne Tiernan told Medical Daily.
The study did, however, have some good news to report – premenopausal women who practice vigorous exercise such as running or biking can decrease their breast cancer risk by 17 percent. The same exercises can lead to a 10 percent decreased risk in postmenopausal women.
"Physically active individuals who exercise outdoors are also likely to have higher sunlight exposure and consequently increased Vitamin D, which may influence cancer risk," the report states.
The study also noted that being overweight or obese throughout adulthood increases the risk of postmenopausal cancer, and that breastfeeding decreases the risk.
Meanwhile, the pros and cons of alcohol have long been debated in medical circles. According to a study released in March, drinking alcohol within recommended limits could be better for you than not drinking at all when it comes to avoiding heart disease. Another study one month prior found that brain damage among drinkers aged 50 and above has trebled over the past 10 years.