How much alcohol is too much?

The thresholds for safe and healthy drinking change with age. Talk to your doctor about your limits.

No doubt you have heard that consuming alcohol in moderation—one to two drinks per day if you are a man—has been linked to better heart health. But whether an alcoholic
beverage is friendly or hostile to your well-being depends on two things: your current health status and how much you drink. A personalized approach is best.

"For some people, depending on what medications you are taking and other factors, even light drinking might not be a good thing," says Dr. Kenneth Mukamal, associate professor of medicine at Harvard-affiliated Beth Israel Deaconess Medical Center. "For other people it could plausibly be beneficial."

Moderate drinking and health

Scores of studies have examined the association between moderate drinking and health, and many find a consistent connection. Observed in large numbers over time, moderate drinkers appear to suffer fewer heart attacks and strokes, less diabetes, and stronger bones in older age, compared with people who drink lightly or not at all. In this case, "moderate" means one to two standard alcoholic drinks per day for men and one drink for women.

Does this mean moderate drinking actively improves health? We are not sure. Perhaps moderate drinkers also eat healthier foods, exercise more, and control stress better. Or, people who don't drink may be avoiding alcohol because they are in poorer health or because it interacts badly with their medications. If so, this would tend to make the moderate drinkers look healthier in comparison.

At the same time, there is no question that excessive drinking spells trouble. In men, the health effects show up as increased heart disease, stroke, and certain cancers—although part of this traces to the tendency of heavy drinkers to also be smokers.

What's safe for you?

Two drinks a day may be safe, but only for the average man. "Two drinks a day is an average distributed across the population," Dr. Mukamal says. "There are inevitably going to be people in that population for whom that is not true."

For example, some research has found that people who limit alcohol to between two and six standard drinks per week have a lower risk of cardiovascular disease than people who drink more. That averages out to less than a drink a day. In fact, the American Geriatrics Society suggests that people over 65—both men and women—should limit themselves to one daily drink. Two drinks a day might cancel the benefit, but still do no major harm.

In the end, it is not possible to offer a firm recommendation because of scientific uncertainties and individual differences in background risk for chronic disease. Dr. Mukamal suggests a "personalized medicine" approach. The assessment starts with a conversation with your doctor about whether moderate drinking is safe and prudent for you. "That's a question well worth asking your physician," he says.

Of course, if you don't drink, don't start in hopes of helping your health. Instead, get regular exercise, eat a healthy diet, and of course don't smoke. These steps will enhance virtually every aspect of your health, from overall mood to sexual potency.

"For people who don't drink at all, the consistent message is don't start," Dr. Mukamal says. "There are so many other ways to make your health better that don't raise the complicated issues that alcohol does."