Drinking a beer has a direct impact on blood glucose levels, particularly for diabetics, resulting in hyperglycemia or hypoglycemia. The amount of beer consumed and the frequency of consumption will determine whether blood glucose levels rise or fall. To minimize the impact, the American Diabetes Association recommends eating food whenever consuming alcohol and limiting consumption to one 12 oz. glass of beer per day for women and two per day for men.
Carbohydrates
Blood glucose provides the body with the energy it needs to survive, and carbohydrates are the main source of blood glucose. Beer contains its fair share of carbohydrates, with the USDA citing roughly 12 g in a 12 oz. serving of regular beer and 6 g in light beer. After consuming carbohydrates, the pancreas secretes a hormone called insulin that works to help the body's cells process the blood glucose as energy. Consuming too many carbohydrates, particularly in diabetics and those with a compromised endocrine system, can potentially result in elevated blood glucose levels, a condition known as hyperglycemia. Insufficient carbohydrate intake can deplete blood glucose reserves, resulting in low blood glucose levels, or hypoglycemia.
Liver Functions
The liver is responsible for several functions, including creating bile to aid digestion, producing vital substances such as albumin and ridding the body of bacteria and toxins. Beer contains alcohol, which the body considers a toxin. Drinking beer puts the liver to work to get rid of the alcohol in the bloodstream. The liver also converts some of the body's blood glucose into a substance known as glycogen, releasing it back into the system when glucose stores become low, ensuring a steady supply of energy to the body.
Moderate Beer Consumption
Drinking even one glass of beer can have an impact on blood glucose levels, particularly when consumed on an empty stomach. Beer contains simple carbohydrates, which the body absorbs very quickly. The pancreas pumps insulin into the bloodstream in response to the carbohydrates, thereby keeping blood glucose levels in check. The liver normally releases glycogen in the absence of carbohydrate intake to keep blood glucose levels normal. When consuming beer, however, the liver is too busy working to rid of the body of alcohol to see to its glycogen duties, and blood sugar levels can dip dangerously low. For most people, the body is able to eliminate the alcohol contained in beer at the rate of 1/2 to 3/4 oz. per hour, roughly the equivalent of one large glass of beer. If beer consumption is kept within these limits, there should be no adverse affects for healthy consumers.
Chronic Consumption
Since the simple carbohydrates contained in beer put the pancreas and liver into overdrive, chronic consumption can lead to adverse side effects. The body can eventually become resistant to the effects of insulin, and the consistent alcohol intake can permanently damage the liver, leading to hyperglycemia in the short term and possibly glucose intolerance and even diabetes over the long term.
References
- USDA: National Nutrient Database for Standard Reference, Release 18 (PDF)
- U.S. Department of Veterans Affairs: What Does Your Liver Do?
- Oregon Counseling; Biological Impacts Of Alcohol Use: An Overview; : Michaele P. Dunlap, Psy.D
- Montana State University: Alcohol Messes with Your Blood Sugar Levels
- American Diabetes Association: Alcohol
