Adults with diabetes can drink moderate amounts of alcohol if they eat food at the same time. For a person with diabetes, the intake should be limited to one drink (defined as a 350 ml beer, 150 ml glass of wine or 45 ml glass of distilled spirits) for women and two drinks for men in one day. Make sure that your friends know you have diabetes and wear some type of diabetes ID (necklace or MedicAlert bracelet) when you are socializing. Always eat something at the same time as you are drinking alcohol. Remember that what you eat should be “long-acting” carbohydrates as the risk of hypoglycaemia extends into the next day. Alcohol containing sugar (liqueur, for example) will cause your blood glucose level to rise for a short time, but then it will drop and you will be at risk of hypoglycaemia. A glass of beer contains about the same amount of carbohydrate as a glass of milk.
It takes a long time for your liver to break down alcohol, which increases the risk of severe hypoglycaemia. Because of this, sleeping late is particularly dangerous the morning after you have been drinking. If you have also been especially active, playing team games or dancing at a club for example, the combined risks of extra activity with alcohol intake put you at much greater risk than usual of severe hypoglycaemia. Under such circumstances, preventing hypoglycaemia becomes imperative.
Alcohol and the liver
Alcohol counteracts the ability of the liver to produce new glucose (a process called gluconeogenesis) by keeping the enzymes occupied with the breakdown of alcohol. The liver can still release glucose from the glycogen store but when this is depleted you will experience hypoglycaemia. The concentration of cortisol and growth hormone in the blood will decrease after alcohol intake. Both hormones have an enhancing effect on the blood glucose level, and this appears 3-4 hours after they are released into the bloodstream. This will contribute to an increased risk of hypoglycaemia many hours after alcohol intake. The liver′s ability to produce free fatty acids will also be impaired. These biological factors come together, making the risk of hypoglycaemia much greater after drinking alcohol. This effect of alcohol will last the entire time it takes the liver to break down the alcohol in your body. The liver will break down 0.1 g (1.5 grains) of pure alcohol/kg body weight per hour. For example, if you weigh 70 kg (150 lb) it will take 1 hour to break down the alcohol in a bottle of light beer, 2 hours for 40 ml of liquor and 10 hours to break down the alcohol in a bottle of wine. Therefore, if you drink during the evening you will be at risk of hypoglycaemia all night as well as part of the next day.