VANCOUVER — A newly released study is throwing cold water on the widely held notion that drinking a small amount of alcohol regularly has a positive impact on one's personal health.
Research spearheaded by the Centre for Addictions Research of B.C. at the University of Victoria re-analyzed data from a slew of long-term studies on alcohol and mortality and found that a bias in their design overestimated the benefits of drinking, while possibly underestimating its dangers.
"We've visited an old chestnut in alcohol health research … , the idea that below a certain level we might call moderate, alcohol is actually beneficial and means that if you drink at that level you may live longer," said Tim Stockwell, the study's co-author and director at the addictions-research centre.
The bias, said Stockwell, is how the research defines abstainers, or those who refrain from drinking.
Most published studies on alcohol and mortality include in this group many people whose poor health has led them to cut down or completely abstain, which in turn makes the health and life expectancy of moderate drinkers look good, he said.
"When you correct for (that bias) it actually appears that the risks at all levels are higher than previously estimated," Stockwell said.
"The takeaway message is, in fact, if anything, we are underestimating the health and safety risks from alcohol."
The literature involved in Stockwell's meta-analysis involved more than four million people, including the identification of 350,000 deaths and their causes.
His findings were published Tuesday in the Journal of Studies on Alcohol and Drugs.
Stockwell emphasized that his research doesn't prove that light drinking is bad, only that the public should be skeptical about the claim that having one or two drinks a day offers a net health gain.
"It may be very pleasurable and enjoyable, and at low levels probably does you very little harm or risk of harm, but I think we shouldn't assume the widespread message is true, that it is actually good for you in moderation," he said.
"I love a beer. I love a glass of chilled wine. But in moderation," he said about his own drinking habits, adding that his own drinking has become more careful since his research began.
"I treat it with more respect."
While additional research has come out in recent years supporting Stockwell's conclusion, the study's findings still go against the grain and threaten to upset the industry that benefits from collective support for the idea that moderate drinking is healthy.
"Those early studies boosted alcohol sales, especially red wine," Stockwell said.
"It's been a major boon to the alcohol industry: 'Drink our product.'"
Stockwell said what lends his particular conclusion strength is that it systematically reviewed 87 other studies, using a refined approach to drill down into data already collected.