A new study has found that drinkers, those that have at least one alcoholic drink a day, have more harmful mouth bacteria than non-drinkers. In addition, drinkers had less beneficial mouth bacteria that keep dangerous microbes in check. The study, led by scientists at the NYU School of Medicine, has been reported in the journal Microbiome.
"Our study offers clear evidence that drinking is bad for maintaining a healthy balance of microbes in the mouth and could help explain why drinking, like smoking, leads to bacterial changes already tied to cancer and chronic disease," said study senior investigator and epidemiologist Jiyoung Ahn, Ph.D.
Ahn is the associate director of population sciences at NYU Langone Health's Perlmutter Cancer Center; she suggested that this work indicates that if a balance is restored in the microbial community residing in the mouth, the oral microbiome, it might reverse some of the health problems linked to drinking. There are about 700 different kinds of bacteria that can live in the human mouth, and scientists are just starting to understand how they affect our health.
In this study, the researchers assessed the oral microbiome of 1,044 people between the ages of 55 and 87, primarily white, who were enrolled in cancer trials. Genetic technology enabled the identification of all the strains of microbes carried by the participants in their saliva; the scientists also had detailed information about the alcohol consumption of participants and divided the individuals into one of three groups - moderate, heavy, and non-drinkers.
It was determined that there was more Bacteroidales, Actinomyces, and Neisseria bacteria, which have the potential to be harmful, in drinkers. Shifts in the levels of these bacteria have previously been associated with cirrhosis and pneumonia. Infections with Actinomyces can cause disease, Neisseria can cause meningitis.
The drinkers also carried fewer Lactobacillales, a type of bacteria often used in probiotic food supplements, and intended to prevent illness.
It remains to be seen if the drinking is directly responsible for the changes seen in the bacterial populations, or if it is due to some other factor that might be associated with drinking, like poor hygiene.
Ahn knows there is much more work to be done and is planning on continuing these studies. Next, she and her team are aiming to understand the mechanisms that underlie changes in the microbiome due to alcohol. There is a lot more to do done, she noted before it’s known how the levels of different kinds of mouth bacterias can be manipulated, and what impact that might have.
Alcohol may also have a negative effect on gut bacteria, as explained in the video.