What drinking wine can and can’t do for you

The latest evidence suggests that wine may help your heart, but it might also raise your risk of cancer slightly.

Consumer Reports offers a few facts you should know about how alcohol consumption (wine or anything else) really affects your health.

The benefits

No matter which studies you look at, any purported benefits associated with drinking are related specifically to “moderate” consumption: one drink per day for women and up to two for men. (Men are allowed more to account for their generally larger size and differences in the way they metabolize, or break down, alcohol.) For wine, one drink is 5 ounces.

If you stick to those amounts, the evidence is pretty clear that alcohol can boost your heart health. “The association between moderate alcohol intake and lower risk of myocardial infarction (heart attack) has been studied in well-designed observational studies for nearly 50 years,” says Kenneth Mukamal, M.D., M.P.H., a professor of medicine at Harvard Medical School who has researched this topic extensively.

“Alcohol affects platelets, acting like a mild blood thinner,”

Mukamal explains. Moderate alcohol consumption also raises HDL cholesterol (the “good” kind), and lowers levels of the blood component fibrinogen, which may also help keep blood thinner.

The Risks

Alcohol has been linked to a small increased risk of cancer in general. A 2015 study published in the British Medical Journal (BMJ) found that compared with nondrinkers, moderate drinkers had a 2 to 6 percent higher risk.

But the association between moderate alcohol intake and the risk of breast cancer was stronger. Women who drank the

amount of alcohol in onethird to one glass of wine per day had a 13 percent increased risk of cancer, mostly driven by breast cancer.

Once drinking goes beyond the small amounts defined as moderate, says Consumer Reports, the risks quickly start to outweigh any potential cardiovascular benefits. Higher levels of alcohol intake are linked to increases in heart disease, high blood pressure, heart attack and stroke, as well as the development of various types of cancer.

The unknowns

The data on alcohol is very consistent, but most of the studies don’t prove cause and effect. Many are observational -- that is, they look at what people do in their real lives rather

than randomly assign people to drink or abstain from alcohol, then follow them to see the effects on their health. The latter type of study would be ideal, but creating a placebo for alcohol to give to a control group is tricky. And attempting to separate large groups of subjects and randomly instruct them to drink or not drink for several years has proved to be almost impossible.

Without that clinical evidence, some experts are reluctant to recommend moderate drinking as a health tactic. Therefore, the American Heart Association and other health organizations advise that if you do drink alcohol, do so in moderation. And if you don’t, you shouldn’t start.