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 your risk of a heart attack or dying is based on flawed data and is most likely wrong, according to a study released today.
A couple glasses of wine aren't going to hurt you, the study found, but they aren't going to help you much either. Heavy drinking, of course, is unquestionably bad for you.
"Our results suggest that light drinking is a sign of good health, and not necessarily its cause," said Kaye M. Fillmore of the UC San Francisco School of Nursing.
"No one should recommend drinking," said Dr. Michael H. Criqui of UC San Diego, who was not involved in the study. Although he said he thought Fillmore underestimated the potential benefits of alcohol, he cautioned that many people used such a recommendation as "an excuse to drink to excess. It's a very dangerous recommendation."
The findings, published online in the journal Addiction Research and Theory, are an outgrowth of ideas first proposed 15 years ago by Dr. A. G. Shaper of the Royal Free Hospital School of Medicine in London.
In his studies on heart disease and death, Shaper observed that many people who abstained from alcohol did so because of advancing age, serious illness or the use of drugs whose effects were altered by alcohol.
He warned then, and has continued to warn, that counting such people as abstainers in alcohol studies would bias the results because their increased likelihood of disease and death was unrelated to the fact that they didn't drink.
But the idea that a couple of drinks are beneficial "is such an appealing hypothesis" that few have taken him seriously, he said.
"It's a lovely story, an appealing story," Shaper said. "Doctors like it, patients like it, everybody likes it."
The paper by Fillmore and an international team of colleagues "is the first time anybody has had a good, critical look at all the evidence," he said.
Fillmore's team identified 54 published reports that examined the health effects of drinking. They found that the majority of the papers included significant numbers of people who had recently quit drinking -- for whatever reason -- among the group who abstained from alcohol.
Seven of the 54 studies included only long-term abstainers -- people who had never consumed alcohol or who had stopped drinking years earlier for reasons unrelated to their current health.
All seven of those studies showed no benefit from moderate drinking.
Fillmore cautioned that the study had not disproved the notion that light drinking was good for health, but "it reopens the debate about this matter."
Criqui said there was some biological evidence to support a health benefit from light drinking. His studies and those of others show that light drinking raises levels of high-density lipoprotein, the so-called good cholesterol.
An evening glass of wine may have some value, he said, "but it is less than previously believed" and he doesn't recommend it.