Drinking affects mouth bacteria linked to diseases

April 24, 2018, NYU Langone Health
Credit: CC0 Public Domain

When compared with nondrinkers, men and women who had one or more alcoholic drinks per day had an overabundance of oral bacteria linked to gum disease, some cancers, and heart disease. By contrast, drinkers had fewer bacteria known to check the growth of other, harmful germs. These are the main findings of a study published in the journal Microbiome online April 23 and led by NYU School of Medicine researchers.

"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," says study senior investigator and epidemiologist Jiyoung Ahn, PhD.

According to Ahn, associate director of population sciences at NYU Langone Health's Perlmutter Cancer Center, her team's study offers evidence that rebalancing some of the 700 types of bacteria in the mouth, or , could potentially reverse or prevent some health problems tied to drinking. Ahn says roughly 10 percent of American adults are estimated to be , which experts define as consumption of one or more drinks per day for women, and two or more drinks per day for men.

Doctoral student and study first author Xiaozhou Fan, MS, says previous studies have examined and its broad links to disease and some changes in the microbiome, but the new report is the first to directly compare drinking levels and their effects on all oral bacteria. Previous work at NYU Langone and elsewhere has tied the risk for head and neck cancers, and for gastrointestinal cancers, to microbial changes in the mouth.

Specifically, drinkers had more of the potentially harmful Bacteroidales, Actinomyces, and Neisseria species, and fewer Lactobacillales, bacteria commonly used in probiotic food supplements meant to prevent sickness.

The study involved 1,044, mostly white participants between the ages of 55 and 87. All came from two ongoing, national cancer trials, and all were healthy when they enrolled in either study and provided mouthwash samples of their oral microbiome, along with detailed information about their alcohol consumption. Laboratory testing was then used to genetically sort and quantify the among the 270 nondrinkers, 614 moderate drinkers, and 160 heavy drinkers. Results were plotted on graphs to determine which bacteria in drinkers stood out—and grew more or less—than in nondrinkers.

Researchers note that while their study was large enough to capture differences between bacteria among drinkers and nondrinkers, more people would be needed to assess any microbiome differences among those who consumed only wine, beer, or liquor. Some 101 wine-only drinkers were involved in the latest study, in addition to 39 who drank only beer and 26 who drank only liquor.

Ahn, an associate professor at NYU Langone in the Department of Population Health, says her team's next steps are to work out the biological mechanisms behind alcohol's effects on the oral microbiome. And she emphasized that her work is still a long way from determining if blocking or promoting any particular changes in the microbiome would lead to healthy bacteria levels similar to those found in nondrinkers.

Possible explanations for drinking-related imbalances, Ahn says, could be that acids in alcoholic beverages make the oral environment hostile for certain bacteria to grow. Another reason, she says, could be the buildup of harmful byproducts from alcohol's breakdown, including chemicals called acetaldehydes, which along with the harmful toxins in the mouth from tobacco smoke, are produced by certain , such as Neisseria.

Explore further: Researchers find bacteria tied to esophageal cancer

Related Stories

Researchers find bacteria tied to esophageal cancer

December 1, 2017
Researchers at NYU Langone Health's Perlmutter Cancer Center report that at least three kinds of bacteria in the mouths of Americans may heighten or lower their risk of developing esophageal cancer.

Pancreatic cancer risk tied to specific mouth bacteria

April 19, 2016
The presence of certain bacteria in the mouth may reveal increased risk for pancreatic cancer and enable earlier, more precise treatment. This is the main finding of a study led by researchers at NYU Langone Medical Center ...

Another reason to break the habit: Smoking alters bacterial balance in mouth

March 29, 2016
Smoking drastically alters the oral microbiome, the mix of roughly 600 bacterial species that live in people's mouths. This is the finding of a study led by NYU Langone Medical Center and its Laura and Isaac Perlmutter Cancer ...

Researchers make important bacterial discovery in oral pre-cancer condition

December 7, 2017
Scientists at the School of Dental Science in Trinity have made an important discovery involving bacteria and a pre-cancerous growth called oral leuoplakia which can precede oral cancer.

Drinking and the risk of cancer

December 11, 2017
It's no secret that drinking alcohol is a risk factor for cancer. The National Cancer Institute says alcohol use is associated with a higher risk of developing cancers of the head and neck, esophagus, liver, breast, colon ...

Don't blame your genes for your toothache, twin study shows

September 13, 2017
For the first time, investigators have looked at the role that genes and the oral microbiome play in the formation of cavities and have found that your mother was right: The condition of your teeth depends on your dietary ...

Recommended for you

A low-gluten, high-fiber diet may be healthier than gluten-free

November 16, 2018
When healthy people eat a low-gluten and fibre-rich diet compared with a high-gluten diet, they experience less intestinal discomfort including less bloating. Researchers at University of Copenhagen show that this is due ...

Youth dating violence shaped by parents' conflict-handling views, study finds

November 16, 2018
Parents who talk to their children about nonviolent ways of resolving conflict may reduce children's likelihood of physically or psychologically abusing their dating partners later—even when parents give contradictory messages ...

Why we shouldn't like coffee, but we do

November 15, 2018
Why do we like the bitter taste of coffee? Bitterness evolved as a natural warning system to protect the body from harmful substances. By evolutionary logic, we should want to spit it out.

Dietary fat is good? Dietary fat is bad? Coming to consensus

November 15, 2018
Which is better, a low-fat/high-carbohydrate diet or a high-fat/low-carbohydrate diet—or is it the type of fat that matters? In a new paper featured on the cover of Science magazine's special issue on nutrition, researchers ...

Low-carb diets cause people to burn more calories

November 14, 2018
Most people regain the weight they lose from dieting within one or two years, in part because the body adapts by slowing metabolism and burning fewer calories. A meticulous study led by Boston Children's Hospital, in partnership ...

Colder, darker climates increase alcohol consumption and liver disease

November 14, 2018
Where you live could influence how much you drink. According to new research from the University of Pittsburgh Division of Gastroenterology, people living in colder regions with less sunlight drink more alcohol than their ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.