One or two alcoholic drinks a day can further reduce the likelihood of heart attack even in men who are already at low risk, new research suggests.

A 16-year study prospectively followed 8,867 nonsmoking male professionals with normal body weight who participated in vigorous daily exercise and ate a healthy diet. Those who drank one-half to two normal servings of wine, beer or hard liquor a day had a 41 to 62 percent reduction of heart attack risk compared with those who drank no alcohol at all. The study was published in the Oct. 23 issue of The Archives of Internal Medicine.

Men who averaged under one-third of a drink a day were no less likely than abstainers to suffer a heart attack, and those who drank more than two drinks a day showed no reduced risk. Statistically adjusting for the use of lipid-lowering and antihypertensive drugs did not alter the results.

“Even in the lowest-risk people, we still find a lower risk associated with moderate drinking,” said Dr. Kenneth J. Mukamal, an associate professor of medicine at Harvard and the lead author of the study.

The researchers pointed out that they did not measure the effects of very heavy drinking, and they emphasized that the alcohol consumption data were gathered by self-reports, which are not always reliable. One author has been a paid speaker at alcohol-industry related conferences.

Dr. Mukamal said he was not prepared to recommend moderate drinking routinely to people who do not drink, and would still want to see a randomized trial to confirm his findings.

But for healthy people who are drinking moderately, Dr. Mukamal said, “there’s certainly no reason to stop.”