Could drinking a bit of alcohol everyday be good for type 2 diabetes?

A new meta-analysis conducted by researchers in China suggests that people with type 2 diabetes may benefit from light-to-moderate drinking, which could have a positive effect on blood glucose and fat metabolism.

The findings were presented yesterday at the Annual Meeting of the European Association for the Study of Diabetes in Barcelona, Spain.

The authors say that people who drank a bit of alcohol every day did not appear to lower blood glucose levels in people who already had Type 2 diabetes, but it did lower blood levels of triglycerides and insulin, as well as improving insulin resistance.

The study suggests that "light to moderate alcohol consumption might protect against Type 2 diabetes," says lead author Yuling Chen from Southeast University in Nanjing, China.

However, recommendations from diabetes organizations such as Diabetes UK remains unchanged; that people with diabetes need to be careful how much alcohol they drink, since alcohol consumption can increase the likelihood of a hypoglycemic episode (also called a hypo) because it reduces blood sugar levels. It can also lead to weight gain and other health problems.

Assessing the impacts of light drinking

For the study, Chen and colleagues used the databases PubMed, Embase, and Cochrane to find randomized controlled trials looking at the association between alcohol consumption and glucose and lipid metabolism among adults with type 2 diabetes. Using computer modeling to analyze data extracted from the trials, the team identified ten relevant trials involving 575 people.

A number of factors associated with diabetes were measured, including blood sugar levels, insulin levels, insulin resistance, cholesterol, and triglycerides.

As reported in the journal Diabetologia, the meta-analysis found that alcohol consumption was associated with a drop in blood triglyceride and insulin levels. It had no significant effect on fasting blood glucose, glycated hemoglobin (HbA1c, a measure of blood glucose control), total cholesterol, low-density lipoprotein (bad) cholesterol or high-density lipoprotein (good) cholesterol.

Light-to-moderate drinking was found to be beneficial

Subgroup analysis showed that light-to-moderate alcohol consumption decreased the average triglyceride level by almost 9 milligrams per deciliter (mg/dL).

Light-to-moderate consumption of alcohol also reduced the average insulin level and a measure of insulin resistance called HOMA-IR.

Chen says the findings suggest that insulin resistance was “relieved” in patients with Type 2 diabetes.
The authors’ defined light to moderate alcohol drinking as a consumption of 20g or less per day, which is about 1.5 cans of beer (330ml, 5% alcohol), a large (200ml) glass of wine (12% alcohol) or a 50ml serving of a 40% spirit such as vodka or gin.

The authors conclude that the findings of this meta-analysis show a positive effect of alcohol on glucose and fat metabolism in people with type 2 diabetes.

Commenting on the research, the team says:

Larger studies are needed to further evaluate the effects of alcohol consumption on blood sugar management, especially in patients with type 2 diabetes."

The study should not encourage heavy drinking

However, Chen warned that you can have too much of a good thing: "High alcohol consumption is reported to be a risk factor for diabetes."

The American Diabetes Association advises that people daily alcohol consumption is limited to no more than one drink for adult women and no more than two drinks for adult men.

Joel Zonszein, Director of the Clinical Diabetes Center at Montefiore Medical Center in New York City, says those are the levels of consumption he recommends to his patients who have Type 2 diabetes:

A little alcohol can be good for you, and that's no different in patients with Type 2 diabetes.”

Some patients should be especially careful

Zonszein does warn of one caveat, which is that people with Type 1 diabetes and people with Type 2 diabetes who are taking insulin or other drugs that can lower blood sugar levels must be especially careful about how much alcohol they drink. Alcohol can sometimes lead to dangerous hypoglycemia.

On the other hand, not all medications taken for Type 2 diabetes pose a risk when alcohol is consumed, says Zonszein. For example, it is fine to drink alcohol while taking the widely used drug metformin.

He also agrees with Chen that drinking excessive drinking is a problem and pointed out that too much alcohol can increase triglyceride levels and lead to serious health issues such as pancreatitis.

Recommendations for people with diabetes

Although drinking one 330ml bottle of beer or a 200 mL glass of wine may not significantly affect a person’s blood sugar level, drinking more alcohol than this tends to initially raise blood sugar.

Alcohol decreases the liver’s ability to turn proteins into glucose, which increases the risk of hypoglycemia once the blood sugar level starts to drop.

Drinking several of these drinks can be expected to cause a rise in blood sugar at first, followed by a steady drop hours later, often once a person is asleep. People who take insulin for their diabetes need to be especially wary of hypoglycemia.

Reactions to alcohol vary from person to person, so it is recommended that people use blood tests to check how their body is responding.

Can a hypo occur whilst a person is drunk?

The symptoms of drunkenness can be very similar to those of a hypo, which can be dangerously confusing. Furthermore, heavy drinking can put a person at risk of a hypo for up to 16 hours or more after they have stopped drinking. Using blood tests to monitor the blood sugar level is essential in this situation.

Does drinking alcohol when you have diabetes pose any other risks?

Drinking heavily on a regular basis can raise blood pressure and the excess calorie intake can lead to weight gain. Drinking alcohol can also exacerbate diabetic neuropathy, increasing pain and numbness.

Drinking low-alcohol drinks may be better than drinking standard alcohol, but there are still dangers; alcohol is often mixed with fizzy, sugary drinks that can affect the blood sugar level.

Annual Meeting of the European Association for the Study of Diabetes (EASD)