Abstract

Introduction- In a randomized controlled trial, we assessed the effect of daily moderate alcohol intake on glycemic control in the fasting and postprandial states in patients with type 2 diabetes who previously had abstained from alcohol.

Methods- We randomized 109 alcohol abstaining patients (41–74 yrs old) with established type 2 diabetes to receive 150ml wine (13g alcohol) or non-alcoholic diet beer (control) each day during a three-month multi-center trial. The beverages were consumed during dinner. Diet and alcohol consumption were monitored.

Results- During the intervention, 17% of participants (12% from the alcohol group) dropped out, leaving 91 who completed the trial. Within the alcohol group, fasting plasma glucose (FPG) decreased from 139.6+/-41 to 118.0+/-32.5mg/dL after 3 months compared to 136.7+/-15.4 to 138.6+/-27.8mg/dL in the controls (Pv=0.015). However, alcohol consumption had no effect on 2-hour postprandial glucose levels (difference=18.5 in the control vs. 17.7mg/dL in the alcohol groups, Pv=0.97). Patients in the alcohol group with higher baseline HbA1c levels had greater reductions in FPG (age-adjusted correlation=-0.57, Pv<0.001). No significant changes were observed in the levels of bilirubin, alkaline phosphatase, ALT, or AST, and no notable adverse effects were reported. Participants in the alcohol group reported an improvement in the ability to fall asleep (Pv<0.001).

Conclusions- Among previous alcohol abstainers with type 2 diabetes, initiation of moderate daily alcohol consumption reduced FPG but not postprandial glucose. Patients with higher HbA1c may benefit more from the favorable glycemic effect of alcohol. Further intervention studies are needed to confirm the long-term effect of moderate alcohol intake.