A glass of wine or a beer with a foamy head can be a great way to relax the mind and compliment a meal. What kind of effects does alcohol have on the trillions of microbes that are found in your digestive tract?
According to Dr. Lorenzo Leggio, a physician-scientist at the National Institutes of Health who researches alcohol use and addiction, “there is a lot that we don’t know,” as is the case with all of the knowledge that pertains to the microbiome.
Despite this, it is abundantly clear that the presence of beneficial bacteria is essential for appropriate digestion, immune system function, and gut health. In addition, as researchers delve more into how drinking might influence your digestive system, they are finding that excessive consumption may have adverse effects.
What changes does drinking to excess bring about in your microbiome?
As stated by Dr. Cynthia Hsu, a gastroenterologist at the University of California, San Diego, the majority of the research that has been conducted on the relationship between alcohol and the microbiota has focused on individuals who drink severely and regularly.
For instance, a few studies have found that individuals who suffer from alcohol consumption disorder, which is defined as the inability to regulate or quit drinking in a harmful manner, typically have an imbalance of “good” and “bad” bacteria in their stomachs. According to Dr. Hsu, this condition is referred to as dysbiosis, and it is frequently associated with abnormally high levels of inflammation and disease in comparison to a microbiome that is healthy.
It was noted by Dr. Leggio that those who consume a lot of alcohol and have dysbiosis may have intestinal linings that are “leakier,” or more porous. According to his explanation, a healthy gut lining acts as a barrier between the interior of the intestine, which is home to microbes, food, and potentially harmful toxins, and the rest of the body.
According to Dr. Hsu, when the lining of the gut becomes damaged, harmful microorganisms and toxins can easily enter the circulation and make their way to the liver, where they can cause inflammation and damage.
An unhealthy stomach may even contribute to cravings for alcohol, according to Dr. Jasmohan Bajaj, a hepatologist at Virginia Commonwealth University and the Richmond VA Medical Center. This is based on preliminary research that has been gathered.
For instance, in a study that was conducted in 2023, researchers investigated the microbiomes of seventy-one persons between the ages of 18 and 25 who did not suffer from an alcohol use issue. When it comes to binge drinking, which is defined as four or more drinks consumed within about two hours for women and five or more drinks consumed by males, those who reported binge drinking more frequently had alterations in their microbiota that were connected with greater alcohol desires. In addition, this study contributed to the findings of previous research that established a connection between binge drinking and increased levels of inflammation in the blood.
The findings of these experiments, however, did not indicate that alcohol was the cause of dysbiosis in humans. In studies conducted on animals, the association is readily apparent; however, when the same studies are conducted on humans, it is more challenging for researchers to account for factors such as food and other health concerns.
But what about those who consume less alcohol?
Consuming no more than two drinks per day for men and no more than one drink per day for women is the definition of moderate drinking according to federal standards. According to Jennifer Barb, a clinical bioinformatics specialist at the National Institutes of Health, there is a lack of research regarding the effects that this quantity of alcohol has on the microbiota in your stomach.
Researchers discovered that those who drink low to moderate amounts of alcohol have more diverse gut microbiomes than those who don’t drink at all. This is a characteristic that is typically connected with having a healthy stomach. It is possible that this is connected to other aspects of lifestyle or food, or it could be that there is something in alcoholic beverages that is beneficial to the microbiome. However, Dr. Barb thinks that it is highly improbable that ethanol is the cause of this.
According to the findings of a study conducted in 2020 on 916 British women who had two or fewer drinks daily, researchers found that those who consumed red wine or, to a lesser extent, white wine had a greater diversity of gut microbes than those who did not consume either of these beverages. It was determined that there was no such association between beer and alcoholic beverages. Polyphenols, which are chemicals that are found in grape skins in high concentrations in red wines, were offered by the researchers as a possible explanation for their findings after investigation.
According to John Cryan, a neurologist who studies the microbiota at University College Cork in Ireland, polyphenols can also be found in things like grapes, the majority of other fruits and vegetables, a variety of herbs, coffee, and tea.
Consuming a wide range of fermented and plant-based foods, such as yogurt, kombucha, and kimchi, can, in general, contribute to the development of a more diverse microbiome.
Can reduce the amount of alcohol you consume to improve the health of your digestive tract?
Within two to three weeks of quitting drinking, the bacteria in the gut of individuals who were being treated for alcohol use disorder began to heal, and the gut linings of these individuals became less “leaky.” This was revealed by researchers who investigated the microbiomes of these individuals. On the other hand, she underlined that individuals who are receiving alcoholism treatment tend to eat healthier and sleep better, both of which can contribute to improved gut health.
The microbiomes of moderate drinkers are not known to be affected by quitting or lowering alcohol intake, according to Dr. Leggio, who noted that it is unclear how or even if this may occur. We do know, however, that drinking alcohol can cause acid reflux, inflammation of the stomach lining, and bleeding in the gastrointestinal tract, in addition to increasing the chance of developing malignancies of the esophagus, colon, and rectal regions.
