Consuming a small-moderate dose of red wine alone can alter the glucose–insulin relationship

Abstract

The aim in the present study was to assess the effect of small-moderate red wine ingestion on the level of serum insulin and plasma glucose when nutritional status is varied. Twenty nondiabetic males (19–22 years) participated in the study. In the fasting trial, all participants underwent a 6 h fast prior to consuming 4 standard units of red wine (40 g alcohol) or the equivalent amount of placebo as dealcoholized wine (containing <0.5% alcohol, 0% resveratrol) over a 135 min period. Alternatively, in the feeding trial, participants consumed food for 45 min prior to ingesting 4 standard units of red wine (40 g alcohol) or placebo over 135 min. Serum insulin and plasma glucose were assessed at regular 45 min intervals during all trials. The results showed a significant decrease in the level of serum insulin and no significant change in plasma glucose concentration in the fasting trial. Alternatively, a significant alcohol-induced decrease in plasma glucose and no change in serum insulin occurred when red wine alone was consumed after food. It was concluded that red wine can alter the glucose–insulin relationship and ingesting red wine alone (without food) should not be encouraged in nondiabetic individuals.