Claims that Drinking a Few Times a Week Reduces Diabetes Risk
WHAT IS THE TRENDING NEWS STORY
A recent article appeared on BBC News based on an interview with a co-author of a Danish research study, Prof. Janne S. Tolstrup. The professor stated, “People who drink three to four times a week are less likely to develop type 2 diabetes than those who never drink”. “Alcohol is associated with 50 different conditions, so we're not saying 'go ahead and drink alcohol'”, she added.
WHY THE STORY HAS MISINFORMATION
Several research studies have investigated the relationship between alcohol consumption and the incidence of type 2 diabetes during the last decade. Two of the most valuable analytical reviews on this topic suggested that moderate alcohol consumption is associated with a decreased incidence of type 2 diabetes, however, the results were inconclusive about the magnitude of this decreased incidence.
These results also raised the question of the effect of the higher amount of alcohol consumption in the development of type 2 diabetes, without ignoring the fact of absence of long-term randomized controlled studies on this matter.
The results of the previous studies have several potential limitations. Most importantly is the measurement error, which is inevitable when using relatively simple methods to assess alcohol consumption, thereby resulting in the observed lowered disease risk in drinkers.
On the contrary, a Swedish study on 5,212 men and women found that high rates of alcohol consumption increase the risk of abnormal sugar levels, particularly in men, while in women the results were more complex; the risk decreased with low or medium intake of alcohol and increased with high alcohol intake.
Similarly, another study on 6,405 northern European men and women in Denmark demonstrated that alcohol consumption was strongly associated with the risk of developing diabetes mellitus. The researchers found that excessive drinkers had the highest risks of developing type 2 diabetes, whereas light drinkers had the lowest risk. Additionally, they found that alcohol was significantly associated with insulin sensitivity and insulin release.
The relationship between alcohol consumption and blood sugar levels has been, and still is, very controversial, especially in different ethnic population. However, some studies suggested that alcohol may have positive effects, such as protecting against diabetes by increasing insulin sensitivity, changing levels of alcohol metabolites, or through the potential anti-inflammatory effect of alcohol.
Furthermore, a study conducted in 2009 to investigate the effects of alcohol intake in individuals who are at high risk for diabetes, again suggested that high levels of alcohol consumption were related to lower insulin secretion, regardless of the level of insulin sensitivity and lower incidence rates of diabetes.
Additionaly, alcohol consumption has its own negative effects; it is well established that excessive alcohol consumption can lead to various liver diseases as well as chronic or acute pancreatitis, which may play a role in the development of type 2 diabetes.
And again, a Danish study found that alcohol accelerated the development of type 2 diabetes in experimental animals.
An important point to mention, which may change everything; an Australian study conducted in 2014 pointed out that the relationship between drinking alcohol and the risk of diabetes does exist, but due to genetic susceptibility rather than the protective effects of alcohol itself.
One has to take into consideration the overlap between the different factors that surround the topic, because it simply increases the possible deviations of the statistical analysis. For instance, diabetic patients who are alcohol consumers are more likely to have poor adherence to anti-diabetic medications which is associated with increased morbidity and mortality.
Finally, another American study showed that alcohol consumption, especially at high levels, can increase the risk of pre-diabetes (higher than normal blood sugar levels, but not high enough to be diagnosed as diabetes). The researchers also found that heavy alcohol drinking is a risk factor for both diabetes and poor treatment adherence.