Swedish scientists have found that alcohol lowers blood sugar by redirecting blood within the pancreas and sending massive amounts of it to the islets.
The finding by the Karolinska Institute in Stockholm, Sweden, is the first to show how alcohol is able to lower blood sugar levels. What happens is that by sending more of the pancreas's internal blood flow to the islets, alcohol spurs insulin production, which in turn lowers glucose levels.
The scientists injected rats with ethanol alcohol and noted that blood flow to the islets increased fourfold. The alcohol did not affect the amount of blood reaching the pancreas, only the distribution of blood within it.
The study also found that alcohol induced the changes in blood flow by affecting nitric oxide, a chemical compound that medical studies suggest is instrumental in glucose transport and the actions of insulin. Alcohol also affected the vagus nerve, which descends from the brain and into the abdomen and, among other things, signals organs there to secrete.
Source: Endocrinology, January 2008