Fewer and fewer people in Germany are drinking alcohol—yet a third of them still consume alcoholic beverages in quantities that are harmful to their health.[1] This issue is particularly relevant for people with diabetes: Alcohol affects blood sugar levels in several ways at once and can—especially when combined with insulin—trigger severe hypoglycemia. To what extent are beer and wine safe, how risky is alcohol for people with diabetes, and what interactions occur between insulin and alcohol?
How much alcohol is healthy?
There is no safe amount of alcohol. According to the World Health Organization (WHO), every sip increases the risk of cancer, cardiovascular disease, and liver damage.[2]
In the past, a glass of red wine in the evening was considered healthy and an after-work beer was taken for granted—but that has changed. 100 to 200 grams of pure alcohol per week (equivalent to about 2.5 liters of beer) shortens life expectancy by an average of six months. After just 30 minutes, alcohol affects attention, reaction time, and self-control—due to changes in blood flow to the brain and the reorganization of neural networks.
Nevertheless, Germans struggle with this: According to data from the Robert Koch Institute, one-third of adults consume alcohol in amounts that are harmful to their health (more than seven drinks per week); even three to six drinks per week are considered problematic. On average, men and those with higher levels of education drink more.[1] The best protection is to avoid it as much as possible.
Why is alcohol bad for your health?
Alcohol is a high-calorie substance that affects metabolism in several ways. At about seven kilocalories per gram, the energy density of pure alcohol is similar to that of pure fat. Depending on the beverage, the impact on body weight and belly fat varies: beer and spirits have a greater effect than red or white wine.
What’s more, alcohol stimulates the appetite and significantly disrupts the body’s metabolic processes. This combination increases the risk of Type 2 diabetes to develop the disease—regardless of body weight.[3]
What happens in the body when you drink alcohol?
Alcohol enters the bloodstream within minutes through the lining of the small intestine and is rapidly distributed throughout the body—including organs and muscles. Organs with a particularly rich blood supply, such as the liver and brain, absorb it the fastest. Peak blood alcohol concentration is usually reached 45 to 75 minutes after consumption.
Can people with diabetes drink alcohol?
In general, the same recommendations apply to people with diabetes as to those without metabolic disorders—with one key difference: blood sugar levels must be monitored more closely.
On an empty stomach, alcohol can cause severe Low blood sugar (hypoglycemia) trigger a condition that is often recognized too late—since the symptoms of hypoglycemia resemble those of intoxication. Especially people who Insulin People who use insulin or take blood-sugar-lowering medications (e.g., sulfonylureas) react to alcohol in different ways, and in some cases, the reaction can be severe. In general, not It is not recommended to take extra insulin just so you can drink alcohol.[4]
What interactions are there between insulin and alcohol?
Alcohol inhibits the liver's release of glucose—and thus significantly increases the risk of hypoglycemia in people who rely on insulin.
Normally, the liver—the body’s main store of blood sugar—continuously releases glucose into the bloodstream, thereby supplying the brain and muscles with energy. Alcohol blocks this process (hepatic gluconeogenesis). The Blood sugar drops. If you inject insulin at the same time, this can quickly lead to hypoglycemia.
In addition, alcohol blocks the effects of glucagon—the hormone that prompts the liver to release sugar reserves when blood sugar levels are low. This dual mechanism makes drinking in the evening particularly dangerous: hypoglycemia occurs with a delay, often while sleeping, when there is no way to correct it.[5]
What should you keep in mind when taking insulin and drinking alcohol?
People with diabetes who take insulin but still drink alcohol should follow these guidelines to minimize the risk of hypoglycemia:
- Never drink on an empty stomach. Eating a carbohydrate-rich meal beforehand slows down alcohol absorption and stabilizes blood sugar levels.
- Check your blood sugar before going to bed. The level should be between 7 and 8 millimoles per liter (mmol/l) before going to bed.
- Keep fast-acting carbohydrates on hand – such as glucose tablets – in case of nocturnal hypoglycemia.
- Do not inject any additional insulin...to "make up for" the alcohol.
- Notify others: In an emergency, caregivers should be aware that the person has diabetes and know whether emergency glucocorticoids or glucagon kits are available.
Summary: Diabetes and Alcohol at a Glance
| Topic | Recommendation / Risk |
|---|---|
| Safe amount of alcohol | None – according to the WHO, there is no safe level |
| Problem drinking (in general) | 3–6 drinks per week; harmful at 7 or more |
| The main risk associated with diabetes | Delayed hypoglycemia due to inhibited hepatic glucose release |
| Special nighttime risk | Nocturnal hypoglycemia in patients on insulin therapy |
| Target blood sugar level before bed | 7–8 mmol/L (approx. 126–144 mg/dL) |
| Eat before drinking | High in carbohydrates – highly recommended |
Frequently Asked Questions About Diabetes and Alcohol
Can alcohol lower blood sugar?
Yes. Alcohol inhibits the glucose release the liver and can thus lower blood sugar—especially in people who take insulin or certain antidiabetic medications. The risk of hypoglycemia increases significantly.
Can alcohol raise blood sugar levels?
Certain alcoholic beverages, such as beer, sweet wine, or mixed drinks, contain carbohydrates that can cause a short-term rise in blood sugar. In the medium to long term, however, the blood-sugar-lowering effect resulting from liver inhibition predominates.
How long does alcohol affect blood sugar levels?
Alcohol’s blood-sugar-lowering effect can last for several hours—even after blood alcohol levels have already dropped. Delayed hypoglycemia is a particular risk at night.
Can people with type 1 diabetes drink alcohol?
There is no outright ban—however, the DDG guidelines recommend exercising particular caution during insulin therapy, monitoring blood sugar levels closely, and never drinking on an empty stomach.[4]
Which drinks are the least problematic for people with diabetes?
Dry wines and straight spirits contain fewer carbohydrates than beer or mixed drinks and have a lesser effect on blood sugar levels due to their carbohydrate content. However, the blood-sugar-lowering effect caused by liver inhibition remains the same for all alcoholic beverages.
Sources
- Robert Koch Institute. Current Health in Germany (GEDA) – Alcohol Consumption in Germany [Internet]. Berlin: RKI; 2023 [accessed Jan. 2024]. Available at: https://www.rki.de/DE/Content/Gesundheitsmonitoring/Studien/Geda/Geda_node.html
- World Health Organization. Alcohol [Internet]. Geneva: WHO; 2023 [accessed Jan. 2024]. Available at: https://www.who.int/news-room/fact-sheets/detail/alcohol
- Knott C, Bell S, Britton A. Alcohol Consumption and the Risk of Type 2 Diabetes: A Systematic Review and Dose-Response Meta-analysis of More Than 1.9 Million Individuals From 38 Observational Studies. Diabetes Care. 2015;38(9):1804–12. https://doi.org/10.2337/dc15-0710
- German Diabetes Society. Clinical Guidelines of the German Diabetes Society – Lifestyle Interventions [Internet]. Berlin: DDG; 2023 [accessed Jan. 2024]. Available at: https://www.ddg.info/leitlinien-empfehlungen/leitlinien
- Turner BC, Jenkins E, Kerr D, Sherwin RS, Cavan DA. The effect of evening alcohol consumption on next-morning glucose control in type 1 diabetes. Diabetes Care. 2001;24(11):1888–93. https://doi.org/10.2337/diacare.24.11.1888
Medical Note: This article is intended solely for general informational purposes and is not a substitute for individual medical advice. People with diabetes should always consult a qualified healthcare professional (diabetologist, primary care physician) before making any changes to their alcohol consumption, insulin dosage, or lifestyle. If you experience symptoms of hypoglycemia, act immediately and seek medical help.
