CAMPOBASSO, Italy -- Moderate drinking has a protective effect on all-cause mortality, not only coronary heart disease, according to a meta-analysis of 34 prospective studies.
CAMPOBASSO, Italy, Dec. 11 -- Moderate drinking has a protective effect on all-cause mortality, not only coronary heart disease, according to investigators here.
In a meta-analysis of 34 prospective studies, a few drinks a day -- one to two for women and two to four for men -- led to lengthier lives, found Augusto Di Castelnuovo, Sc.D., of the Catholic University here, and colleagues.
"Our data show that consumption of little amounts of alcohol leads to a reduction of mortality up to 18%," Dr. Di Castelnuovo said. But, he cautioned, "after a certain number of glasses things radically change" and the risk of death rises again.
The finding was based on an analysis of studies involving 1,015,835 persons and 94,533 deaths, Dr. Di Castelnuovo reported in the Dec. 11 issue of the Archives of Internal Medicine.
Previous studies have shown an inverse relationship between moderate alcohol consumption and coronary heart disease, Dr. Di Castelnuovo and colleagues said, but this is the first to show a similar effect for all-cause mortality.
The researchers defined a drink as 10 grams of ethanol and found that women benefited when they had a daily intake of between 10 and 25 grams, while men had a benefit from about 20 grams to 42 grams.
The benefit, however was roughly the same, they said:
For women the results were comparable regardless of where the study took place, the researchers said, but for men there were significant geographical differences.
In particular, European men had a maximum risk reduction between 20% and 28%, while American men benefited to the tune of between 14% and 19%.
What's more, the researchers said, the protection extended up to six drinks a day in European studies, but stopped short - at three drinks per day -- in U.S. studies.
That finding, the researchers said, might be a function of differences in the way American and European men drink.
"It is also the way we drink that makes the difference," said co-author Giovanni de Gaetano, M.D., Ph.D., also of the Catholic University.
"Little amounts, preferably during meals -- this appears to be the right way," he said. "The rest of the day must be absolutely alcohol- free."
The researcher noted that confounding factors could still have played a role in the finding - especially the suggestion that people who drink moderately are more concerned about their health in the first place and might be, for example, more physically active.
But Dr. Di Castelnuovo said the researchers adjusted their results for a range of possible outside factors and "our data suggest that, even considering all main confounding factors (such as dietary habits, physical activity, or the health of people studied), a moderate consumption of alcoholic beverages keeps on showing a real positive effect."
The study was financed by the Italian research ministry. He researchers reported no financial conflicts.