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The Effect of Alcohol on Blood Glucose

How does alcohol consumption affect blood glucose levels? What is a rule of thumb when considering alcohol intake? What amount is allowed, and do you take extra diabetes medication for alcohol? What, for example, is the carb content of a 4 oz glass of wine?
It is a common misconception that alcohol "turns to sugar" and will raise your blood glucose. In fact, the opposite is true--alcohol can lower your blood glucose.
How Alcohol Works on the Body
- Alcohol is not food, and it does not provide any essential nutrients; even though your body can use the calories for energy, it cannot use the alcohol itself to make glucose. When calories from alcohol aren't used for immediate energy, they are changed to fat and stored as triglycerides. In other words, it is easier to think of alcohol as being like a fat, rather than a carbohydrate. And actually, as Sheldon Gottlieb, MD stated in the April, 2004 issue of Diabetes Forecast: "Alcohol is not a carbohydrate. Alcohol is a drug, the most widely available and the most widely consumed drug in our culture."
- According to the United States Department of Agriculture (USDA) National Nutrient Database for Standard Reference web site, a 3.5 oz glass of white wine has less than 1 gram of carbohydrate; similarly, a 3.5 oz glass of red wine has under 2 grams of carbohydrate.
- Normally, if you haven't eaten for a while, your body uses its liver stores of glucose (called glycogen) for energy. When these stores are used up, the liver makes glucose from other sources. However, alcohol inhibits the liver from making glucose, so if you haven't eaten, you run the risk of low blood glucose (hypoglycemia). In addition, alcohol can increase or prolong the action of your insulin or oral agents. In fact, the glucose-lowering action of alcohol can last 8 to 12 hours after you had your last drink.
- Mixing alcohol and exercise can further increase the risk of low glucose: After exercise, your body is busy replacing the energy your muscles used, by taking glucose from the blood and adding it back into the muscle stores. If you take diabetes medication, these drugs are also helping to clear glucose from the blood, to put it into your cells; since alcohol stops the liver from sending out glucose, unless you eat adequately (and perhaps lower your diabetes medication before exercise), you increase the risk of hypoglycemia.
- If you had alcohol in your system and had such a severe low glucose that caused you to go unconscious, a glucagon shot may not work. This is because glucagon works by telling your liver to release more glucose into your bloodstream, but alcohol blocks that process. So in this situation, you would need to have glucose injected directly into your bloodstream (by a healthcare professional)-not glucagon.
- Alcohol can worsen neuropathy (nerve damage), because it is toxic to nerves, which can increase the pain, burning, tingling, numbness, and other symptoms found in nerve damage
- Heavy drinking can aggravate eye problems as well as high blood pressure
- Alcohol can affect your judgment making it more difficult to recognize the warning signs of hypoglycemia and to respond appropriately
General Guidelines for Alcohol
- For weight control purposes, it would be wiser to consider alcohol as a fat, which means you need to have it in moderation
- One drink is defined as: 5 ounces of wine, 12 ounces of beer or 1.5 ounces of spirits. The American Diabetes Association recommends: for women, no more than one alcoholic drink (or less) a day, and for men, two or fewer drinks per day.
- Never take extra insulin or oral agents with alcohol, as this could result in hypoglycemia. Likewise, never omit food from your meal plan when you have alcohol
- Never drink on an empty stomach
- Be sure to check your blood glucose frequently after consuming alcohol
- Wear your diabetes medical I.D.
- Talk to your doctor or diabetes educator to learn if alcohol is safe for you, as well as the best way to incorporate alcohol into your meal plan
Conclusion:
This doesn't mean you can't drink alcohol just because you have diabetes. It just means you need to take the above information into consideration, and realize that alcohol should be considered a "treat" and not a substitute for other food.
Resource Links
DOC09521-Rev-C 04/09