More than 50 percent of adult Americans, including diabetics and others with chronic medical conditions, drink alcohol on a regular basis. Alcohol is metabolized by your liver, where glucose, fatty acids and other chemicals are also processed. Alcohol impinges on the cellular pathways that are needed for glucose and fatty acid metabolism, which has important implications for diabetics. Alcohol’s ultimate effects on your blood glucose level depend on whether you consume it with food and on what types of foods you eat while drinking.
Fasting
During periods of fasting, your liver manufactures glucose to provide essential fuel for your other tissues and organs. Alcohol interrupts this process. Whenever you consume alcohol, it is rapidly oxidized in your liver via three enzymatic pathways. The chief product of each pathway, acetaldehyde, is quickly converted to acetate in your liver’s cells, a process that generates hydrogen ions. The excess hydrogen converts pyruvate, a necessary ingredient in new glucose production, to lactate. The net effect is a drop in glucose production within your liver. Thus, when consumed without food, alcohol can lower your blood glucose level, an effect that is magnified if you haven’t eaten for several hours.
A Drink with Dinner
According to a July 2004 report in “Diabetes/Metabolism Research and Reviews,” when you consume alcohol with a carbohydrate-containing meal, your liver metabolizes the alcohol before it deals with the carbohydrates. This processing hierarchy leads to a “backup” of carbohydrates – namely glucose – in your bloodstream. This is manifested by a higher-than-normal after-dinner blood glucose level, which triggers a robust insulin surge from your pancreas. Once the alcohol is metabolized, the queued glucose is quickly consumed by your insulin-sensitized liver. Hence, a drink of alcohol with a meal provokes an initial increase in blood glucose that is potentially followed by an abnormally low glucose level several hours later.
Diabetes and Alcohol
The hallmark of diabetes is disrupted carbohydrate metabolism and chronically elevated blood glucose levels. Clearly, alcohol can trigger swings in your blood glucose that require careful monitoring if you are diabetic. Although light-to-moderate alcohol use offers some of the same health benefits to diabetics that it does to non-diabetics, if your diabetes is not well controlled – or if you do not monitor your blood glucose regularly – you should avoid drinking alcohol.
Considerations
Whether or not you are diabetic, alcohol consumption can cause exaggerated swings in your blood glucose level. Drinking on an empty stomach typically prompts a fall in blood glucose, while having a drink with food usually leads to higher-than-normal blood glucose levels. Eating refined carbohydrates, such as cookies, cakes and chips – a frequent consequence of “social” drinking – often leads to an initial rise in your blood glucose followed by a precipitous drop, a condition called reactive hypoglycemia. If you are diabetic, ask your doctor if you should drink alcohol.
References
- Centers for Disease Control and Prevention: FastStats – Alcohol Use
- “The Merck Manual of Diagnosis and Therapy, 18th Edition: Alcoholic Liver Disease”; Mark H. Beers, M.D., Editor-in-Chief; 2006
- “Diabetes/Metabolism Research and Reviews”; Diabetes Mellitus and Alcohol; A. van de Wiel; July/Aug 2004
