A new study offers good news for women who unwind with a cocktail at the end of the day: light to moderate drinking is associated with lower stroke risk.
The new report by researchers at Brigham and Women’s Hospital involved 26 years of data on 83,578 women who were part of the long-running Nurses’ Health Study — a federally funded study of how such factors as diet, alcohol consumption and other lifestyle factors may influence women’s long-term health.
Over the follow-up period, there were 2,171 reported stroke events: 1,206 were ischemic strokes, which occur when a blood vessel supplying blood to the brain is blocked by a clot, and 363 were hemorrhagic strokes, when a blood vessel in the brain weakens and bursts. The rest were of an unknown type.
On average, about 35% of women reported very low levels of alcohol consumption — less than 4.9 grams, or less than half a glass of wine, a day. About 37% drank moderately — 5 to 14.9 grams daily, or a half to one and a half glasses of wine, one serving of a mixed drink, or one beer. Approximately 11% reported drinking more than the equivalent of one mixed drink per day and 30% reported abstaining from alcohol completely.
The researchers found that women who consumed low to moderate amounts of alcohol had a lower risk of stroke than women who never drank. Why would drinking lower stroke risk? “Alcohol has components that prevent blood clots and promote HDL (good) cholesterol,” says lead researcher Dr. Monik Jimenez. Fewer blood clots could account for fewer strokes. (And the boost in good cholesterol helps explain why moderate drinking may also lower the risk of heart disease.)
But keep in mind that heavy drinking can have adverse stroke effects. While the population of women in the study who drank heavily was too small to say much about their stroke risk, previous research has shown that overconsumption isn’t healthy. “Higher intake can lead to high blood pressure and atrial fibrillation which are both risk factors for stoke,” says Jimenez. “Our findings really stress moderation for women who do drink.”
But that’s not an invitation for women who don’t drink to start boozing now. Although the researchers found an association between stroke risk and alcohol, they did not find a cause-and-effect relationship. Also, the risk of stroke in women who abstained from alcohol was still relatively low. “We do not advocate alcohol consumption from those who abstain from drinking,” says Jimenez. “There are a lot of risks associated with drinking and there are other healthy lifestyle modifications women can make instead.”
Based on their findings, the researchers support the American Heart Association’s (AHA) message that men and women who consume alcohol should do so in moderation.
Below, a few tips from the AHA on drinking:
- Moderate drinking for men means one to two drinks per day and one drink per day for women
- The risks and benefits of alcohol consumption should be reviewed periodically as part of regular medical care
- People who should not consume any alcohol: anyone with a personal or family history of alcoholism, high blood fats, pancreatitis, liver disease, certain blood disorders, heart failure, and uncontrolled hypertension, as well as pregnant women and people on certain medications that interact with alcohol
The study is published in the March 8 online issue of Stroke, a journal of the AHA.