Only a couple decades ago alcohol was prohibited in diets recommended for diabetics, but in the 1980s, newer concepts in the management of diabetes favoured a diet that was more liberal in carbohydrate content and allowed for more flexibility for individual patients. These changes were employed to increase compliance with physicians’ dietary recommendations. Prominent researchers, such as Janet McDonald of the Food and Drug Administration, successively argued for the inclusion of moderate alcohol consumption in a diabetic regime once scientific research haddemon-strated that moderate alcohol intake did not impair–and in some studies improved–glucose response. The American Diabetes Association (ADA) states, "Blood glucose levels will not be affected by moderate use of alcohol when diabetes is well controlled." Referring to the USDA Dietary Guidelines for Americans, the ADA defines moderation as no more than two drinks per day (12g) for men and no more than one for women.

Evidence from four large population studies suggests that moderate alcohol consumption may have favorable effects on insulin sensitivity for adult individuals across cultures. In 1995 Harvard University researchers reported in the British Medical Journal that men who consumed two drinks per day had a 40% reduced risk of developing diabetes. A second study from England found results comparable to the Harvard study with reduced risk statistically stronger in men with pre-existing evidence of heart disease. Earlier this year, a University of Wisconsin study published in the Journal of the American Medical Association reported that moderate drinking may reduce CHD risk in those who already have diabetes. Also in 1999, moderate alcohol consumption appeared to reduce risk of diabetes significantly in a fourth study conducted in Japan and published in Diabetes Care.

The Harvard researchers led by E. Rimm from the Harvard School of Public Health, analysed 41,810 male health professionals aged 40-75 for six years, who were free of diabetes at the start of the study. After the scientists accounted for risk factors such as weight and smoking, they found that men who consumed 2-4 drinks per day had a 40% reduced risk for diabetes as compared to abstainers. The researchers noted that these findings were similar to a four-year follow up of women in the Nurses’ Health Study (Stampfer et al) which also indicated reduced risk for moderate drinkers and increasing risk for heavier drinkers. Rimm et al concluded, "Moderate alcohol consumption among healthy people may be associated with increased insulin sensitivity and a reduced risk of diabetes". The British team, led by Perry, examined the associations between moderate alcohol consumption, type 2 diabetes and CHD in a cohort study of 7,735 men aged 40-59. "A shallow ‘U shaped’ relation was seen between alcohol intake and the risk of diabetes, with the lowest risk seen in moderate drinkers relative to the baseline group of occasional drinkers." concluded the team, reporting in the BMJ.The 1995 British finding supports evidence reported by the University of Wisconsin of 983 men (average age 68 years) who had type 2 diabetes at the outset of the research. In comparison with men who had never consumed alcohol and abstainers who used to drink, the death rates from CHD in moderate drinkers were significantly lower . Tsumura et al, reporting in Diabetes Care, examined the relationship between daily alcohol consumption and type 2 diabetes in 6,362 men aged 35-61 who were free of illness at the start of the study. This research is part of the Osaka Health Survey which measures risk factors for many other chronic diseases. After a 4-16-year observation period, the team reports, "Among men with a higher BMI (body mass index), moderate alcohol consumption (29.1-50.0ml/day) is associated with a decreased risk for type 2 diabetes". .

The research suggest that there is an inverse correlation between moderate alcohol consumption and risk for type 2 diabetes. The four studies reviewed are notable due to their size, extensive follow up, diverse populations and consistent results. However, researchers continue to caution against a general recommendation to begin drinking. M.Cirqui, MD states in the Wisconsin study, "While evidence is mounting that light to moderate alcohol consumption may be associated with reduced insulin resistance and lower CHD risk, serious problems preclude extrapolating these findings to treatment recommendations." This is supported by ADA which stresses the importance of individuals and physicians working together to make decisions regarding consumption, whether or not the patient has diabetes.

Though these results may not yet translate to general patient care, learning more about the association between alcohol consumption and risk for type 2 diabetes will help improve the understanding of this condition. In light of research associating moderate alcohol consumption, increased insulin sensitivity and reduced risk for coronary heart disease in diabetics, new insights into the etiologies of both diseases may be on the horizon.

This article is for educational purposes only, and it should not be used for marketing or advertising. The reader is urged to obtain the full scientific articles to review all the points made by each research team