Moderate drinkers may be less at risk for developing type 2 diabetes than nondrinkers and heavy drinkers, according to research by Ming Wei, MD, and his colleagues at the Cooper Institute in Dallas, Texas. The research was published in the January 2000 issue of Diabetes Care. Wei’s team examined the effect of alcohol consumption and the rates of type 2 diabetes in 8,663 men in the state of Texas. Over 6 years, 149 subjects developed diabetes.
Tests conducted by the researchers included the measurement of waistlines, blood pressure, cardiorespiratory fitness, HDL cholesterol, serum triglyceride concentration, smoking status, fasting plasma glucose as well as the filling out of a questionnaire by the test subjects.
It was found that diabetes risk was lowest in those men who drank between 5 and 10 drinks per week. Researchers believe that moderate drinking may enhance insulin sensitivity and improve the glucose response to the digestion of carbohydrates.
Of the 8,663 men tested, 40% consumed 10 to 22 drinks per week, and as a result had 1.8 times higher risk for developing diabetes than those who were consuming only 5_10 drinks a week. Of this higher-risk group, 24% of the diabetes incidence may be blamed on high alcohol intake. This may be explained by earlier research which showed that large amounts of alcohol decreases insulin-mediated glucose uptake and that alcoholics have decreased glucose tolerance. This is probably due to the toxic effect of alcohol on pancreatic islet cells, or to the inhibition of insulin secretion and an increase in insulin resistance.
Interestingly, nondrinkers had a higher risk of developing diabetes than the heavy drinkers-1.8 times higher than the moderate drinkers.
A few problems with the study may lie with the demographic; 97% of the participants were white men from Texas, with “white-collar” or professional occupations. This may preclude an accurate assessment of women and other ethnic groups. Additionally, as with all current studies, these findings are based on alcohol intake as self-reported in questionnaires. Therefore, statements of previous drinking habits are not verifiable. This might have led to a misclassification of a participant.
According to the Cooper Institute, this very homogeneity should be considered an advantage; as it limits any variables. But the results of the study still need to be compared to any future results which consider women, other socio-economic groups, or ethnic minority. It would also be germane to assess studies on animals as confirmation.