There’s still quite a bit scientists do not know about the microbiome: the vast collection of microorganisms living within your body. What is becoming increasingly clear, however, is that peoples lifestyle and habits, from the foods they consume to the medications they take, may influence these bacterial colonies.
Even drinking seems to have an effect.
A new study, published Tuesday in the journal Microbiome, finds that drinking alcohol may alter some of the approximately 700 types of bacteria in a person's mouth and probably not for the better.
The study finds that alcohol may give rise to strains of oral bacteria that are linked to a heightened risk of some types of cancer, gum disease and heart disease, while simultaneously suppressing varieties that can protect the body from infection.
Past research has found similar results in animals, but the new paper is among the first to demonstrate such a link in humans.
“We know that alcohol is a risk factor for many other diseases,” says senior investigator Jiyoung Ahn, an epidemiologist at the New York University School of Medicine.
“This is another scientific rationale or justification, that heavy drinking is not recommended. We should avoid heavy drinking in terms of maintaining a healthy microbiome.”
The study looked at 1,044 adults: 270 of whom didn’t drink, 614 of whom drank moderately (one drink per day for women, and one or two drinks per day for men) and 160 of whom drank heavily (more than a drink per day for women, and more than two drinks per day for men).
Each person swished with mouthwash, then handed the sample over for genetic analysis. They also filled out detailed health and lifestyle questionnaires.
After sequencing the bacterial colonies, the researchers found some clear differences in the oral microbiomes of drinkers versus non-drinkers. Drinkers had higher levels of three strains of bacteria linked to disease including cancers of the head, neck, esophagus and pancreas and less of a type of bacteria that may protect the body from germs.
The more someone drank, Ahn says, the more pronounced these effects tended to be. These differences are likely due to the way bacteria interacts with compounds in alcohol as it’s metabolized, Ahn says.
As with most microbiome findings, Ahn cautions that more research is required to truly understand the way bacteria interacts with the body. In future studies, she plans to examine the specific ways different types of alcohol, such as wine, beer and liquor, affect the mouth.
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