San Francisco ? If you think a glass of wine in the evening is good for your heart, think again.

The long-held belief that moderate drinking reduces risk of a heart attack is based on flawed data and is most likely wrong, according to a new study released today.

A couple glasses of wine aren’t going to hurt, the study found, but they aren’t going to help much either. Heavy drinking, of course, is unquestionably bad.

“Our results suggest that light drinking is a sign of good health, and not necessarily its cause,” said epidemiologist Kaye M. Fillmore of the University of California, San Francisco School of Nursing.

“No one should recommend drinking,” said Dr. Michael Criqui of UC San Diego, who was not involved in the study. Although he thinks Fillmore underestimates the potential benefits of alcohol, he cautions that many people use such a recommendation as “an excuse to drink to excess. It’s a very dangerous recommendation.”

The new findings are published online in the journal Addiction Research and Theory.