The news is good for those of us who enjoy a glass of wine, beer or a mixed drink a day. A new study of more than 80,000 women revealed that low to moderate alcohol consumption is associated with a 17% to 21% reduction in risk of stroke.
The new findings were published last week in Stroke, the online journal of the American Heart Association. For the study, researchers looked at data on nearly 84,000 women who were part of the Nurse’s Healthy Study, in which they had to provide information on their daily diets, lifestyle habits, and how much they drank. All of the women had no evidence of cancer and heart disease when the study started, and were enrolled in the study for 26 years.
Scientists have been questioning how alcohol affects the risk of stroke, given that moderate drinking appears to lower the risk of heart disease. It probably does that by boosting the production of HDL, the good cholesterol, and reducing the risk of blood clots.
During the study, scientists found 2,171 incidents of strokes, including ischemic strokes (when blood flow to the brain is obstructed), hemorrhagic strokes (where a brain blood vessel bursts), and strokes of unknown origin. They also found almost 30 percent of women reported that they never drank alcohol, 35 percent reported drank very little, 37 percent drank moderately, and only 11 percent of women reported drinking more than the equivalent of one mixed drink per day on average.
Women who drank low to moderate amounts of alcohol–from less than 1/2 a glass of wine per day to 1.5 glasses of wine, one serving of a mixed drink, or one beer –had a lower stroke risk than women who never drank. But heavy drinkers were no less likely to suffer a stroke.
Because there were so few heavy drinkers, this study doesn’t give a reliable picture of risk for women who drink heavily. But earlier studies have found that heavier drinking is linked to more strokes.
“At higher levels, [alcohol] can increase blood pressure,” Monik Jimenez, the epidemiologist at Brigham and Women’s Hospital who led the study told NPR. Drinking a lot also can increase the risk of an irregular heartbeat called atrial fibrillation, which boosts the risk of stroke.
These results, while positive, are not an invitation to park yourself at the bar. In fact, Jimenez says, women who don’t drink can feel perfectly comfortable with that choice, because their risk of stroke is still relatively low. “We certainly don’t want to advocate initiation of alcohol consumption for those who are non-drinkers.”