The government Tuesday warned that a few drinks a day may not protect against strokes and heart attacks after all.
Some studies in recent years have touted the health benefits of moderate drinking. Some have even said that up to four drinks a day can significantly reduce the risk of heart disease in people 40 and older.
But researchers at the Centers for Disease Control and Prevention analyzed data from 250,000 Americans who participated in a 2003 telephone survey. They found that the nondrinkers had many more risks for heart disease — such as being overweight, inactive, high blood pressure and diabetes — than the moderate drinkers.
Based on those results, the agency could not say that moderate drinking actually was a factor in reducing the risk of heart disease.
The findings were published in the May issue of the American Journal of Preventive Medicine.
"We're feeling the pendulum has swung way too far and Americans are getting sort of the wrong idea" on alcohol, said the study's lead author, Dr. Tim Naimi of the CDC's chronic diseases division. "The science around moderate drinking is very murky."
Moderate drinkers tended to be in better health, better educated, wealthier and more active than their nondrinking counterparts, and that likely influenced their lower risk of heart disease, the study said.
"It appears that moderate drinkers have many social and lifestyle characteristics that favor their survival over nondrinkers and few of these differences are likely due to alcohol consumption itself," the study said.
The CDC has long worried about alcohol abuse in the United States. Studies have shown that drinking excessively — five or more drinks daily — can increase the risk of heart disease. The CDC says nearly one in three Americans drinks too much.
The agency said that Americans should follow dietary guidelines that limit daily consumption to two drinks for men and a single drink for women.
Other groups — such as the American Heart Association — say drinking alcohol increases the dangers of alcoholism, high blood pressure, obesity, stroke, breast cancer, suicide and accidents.
Dr. Daniel Fisher, a cardiologist with New York University Medical Center, said the CDC's findings should also be treated with caution because the average person interviewed in the phone-based study may not be completely forthcoming about their alcohol consumption. He added that a clinical trial is needed to fully determine whether alcohol drinking provides health benefits.
Alcohol is the nation's third leading cause of death, killing 75,000 Americans each year through related injuries or diseases, the CDC says.