Aims: To investigate the association between alcohol consumption and impaired glucose tolerance and Type 2 diabetes mellitus.
Methods: A population-based cross-sectional study consisting of 3,128 Swedish men, aged 35-56 years. Oral glucose tolerance testing identified 55 cases of Type 2 diabetes and 172 cases of impaired glucose tolerance. Information on alcohol consumption, family history of diabetes, smoking and physical activity was obtained by questionnaire.
Results: After adjustment for family history, smoking, physical activity and body mass index, the odds ratio of diabetes was 2.1 (95% confidence interval (CI) 1.0-4.5) in men with high consumption of alcohol (corresponding to over 12 drinks per week) and 0.7 (0.3-1.8) in moderate consumers (7-12 drinks), compared to occasional drinkers. For impaired glucose tolerance, the corresponding odds ratios were 0.7 (0.5-1.1) and 0.6 (0.4-1.0), respectively. Separate analyses for type of beverage indicated that high consumers of beer, spirits and wine had an odds ratio for diabetes of 2.9 (1.2-6.9), 3.3 (1.4-7.8) and 1.2 (0.5-2.7), respectively.
Conclusions: The results indicated that high consumption of alcohol increases the occurrence of Type 2 diabetes and that this may primarily concern consumption of beer and spirits. For impaired glucose tolerance, regular alcohol consumption was associated with a reduced prevalence, particularly at moderate levels.