A few years ago here at Diabetes Flashpoints, we discussed the relationship between drinking alcohol and the risk of developing Type 2 diabetes. As we noted then, numerous studies have found health benefits from moderate drinking, including lower risks of cardiovascular disease, dementia, and death from all causes. Moreover, it appeared then that in comparison with nondrinkers, moderate drinkers have a lower risk of developing Type 2 diabetes.
But a recent analysis — published last month in the Journal of Studies on Alcohol and Drugs — calls into question many or most of the supposed health benefits of moderate drinking. As noted in an article on the study at Medical News Today, researchers at the University of Victoria in Canada examined 87 different studies on the relationship between drinking and longevity. They were looking for flaws in how the studies were designed, especially in how they defined “abstainers,” or people who don’t drink.
In most of the studies, abstainers were defined simply as people who don’t currently drink any alcohol. This can lead to problems when comparing nondrinkers with moderate drinkers, because many people who don’t drink have stopped doing so because of a health problem — not because they simply chose to abstain from drinking for an extended period of time. This means that moderate drinkers were compared against a group that was disproportionately sick, and their higher rate of illness wasn’t due to their lack of drinking.
In 13 of the 87 studies, however, researchers accounted for this potential for bias and corrected it by making sure that their nondrinkers weren’t abstaining due to health problems. But in these studies, no longevity benefit was found from moderate drinking compared with not drinking at all. Furthermore, when the authors of the new analysis corrected for the effect of sickness among nondrinkers in the vast majority of studies that didn’t account for this bias, the longevity benefits from moderate drinking disappeared.
In fact, the researchers found, it was occasional drinkers — those who have less than one drink per week — who showed the greatest longevity across the 87 studies. Since this very low dose of alcohol was extremely unlikely to have any effect — positive or negative — on mortality, the researchers concluded that their longevity must be due to some factor other than their (low) alcohol consumption, compared with nondrinkers. But just what that factor could be remains a mystery.
What’s your take on alcohol and your health — do you think it’s a healthy practice, in moderation? Do studies on the health effects of drinking have any effect on your habits, or do you drink — or not drink — for other reasons? Since drinking is often accompanied by social interaction, do you think it’s foolish for scientists to try to isolate the health effects of drinking, without taking the social benefits into account? Do you think the choice of beverage matters? Leave a comment below!