A number of studies have found an association between moderate drinking and a relatively lower risk of developing type 2 diabetes. However, whether that reflects a benefit of alcohol has been unclear. A central issue is the fact that, compared with both non-drinkers and heavy drinkers, moderate drinkers tend to have a generally healthier lifestyle.
In a new study, researchers found that among more than 35,000 Dutch adults followed for a decade, those who averaged a drink or two per day were 45% less likely than teetotalers to develop type 2 diabetes.
Moreover, the lower risk was seen among men and women whose diabetes risk was already relatively low because of their weight and lifestyle habits -- namely, not smoking, eating a healthy diet and getting regular exercise.
Even among study participants with at least three of those protective factors, moderate drinkers were 44% less likely than non-drinkers to develop type 2 diabetes.
The findings, reported in the American Journal of Clinical Nutrition, suggest that the alcohol-diabetes connection is not explained away by other lifestyle factors.
“Our results indicate that this is very unlikely, because moderate drinkers with the most healthy lifestyle behaviours...had a lower chance of developing diabetes compared with subjects with these healthy lifestyle behaviours who did not drink,” lead researcher Dr. Michel M. Joosten, of Wageningen University in the Netherlands
The findings are based on 35,625 adults who were between the ages of 20 and 70 and free of diabetes, heart disease and cancer at the outset. Participants had their weight, height and waist and hip circumference measured and completed questionnaires on their health Over the next 10 years, 796 developed type 2 diabetes.
Moderate drinkers - up to a drink per day for women, and up to two for men - were less likely to develop the disease than non-drinkers. And that remained true when Joosten and his colleagues examined the effects of other lifestyle-related factors.
For example, when they looked only at normal-weight men and women, moderate drinkers were 65% less likely to develop diabetes than teetotalers. Similarly, among regular exercisers, moderate drinkers had a 35% lower risk of diabetes.
The ‘take-home message,’ Joosten said, is that moderate drinking “can be part of a healthy lifestyle to lower your risk of type 2 diabetes, even if you already comply with multiple other low-risk lifestyle (behaviours).”
Lay Summary by Professor R Curtis Ellison: In a very well-done analysis from a large Dutch population, it was shown that moderate drinking considerably lowers the risk of developing type 2 diabetes even among subjects who are otherwise following a healthy lifestyle (not obese, non-smokers, physically active, eating a healthy diet). Thus, it indicates that the effect of moderate drinking on lowering the risk of diabetes cannot be explained by other healthy lifestyle habits of such drinkers. Moderate drinking should be considered as a complement, and not as an alternative, to other healthy lifestyle habits that lower the risk of chronic diseases such as diabetes and coronary heart disease.
To view a detailed critique of this paper by ISFAR visit www.alcoholforum4profs.org
Article: Joosten MM, Grobbee DE, van der A DL, Verschuren WWM, Hendriks HFJ, Beulens JWJ. Combined effect of alcohol consumption and lifestyle behaviors on risk of type 2 diabetes. Am J Clin Nutrition, published on-line 21 April 2010. doi:10.3945/ajcn.2010.29170