Drinking alcohol may do more than just damage the liver — it may mangle with the balance of good and bad bacteria in one's mouth, which in turn could yield other more pressing consequences than just bad breath.
A person's mouth typically contains 700 types of bacteria, a mixture of good and bad ones, but people who drank one or more alcoholic beverages per day have more bad bacteria than good, a new study has discovered.
Too much bad bacteria in the mouth is known to be linked to gum disease, heart problems, and even some types of cancers.
"This is the first comprehensive study of alcohol intake on oral microbiome," said Jiyoung Ahn, the study's senior investigator and an epidemiologist at the New York University's School of Medicine. The findings were published in the Microbiome journal on April 23, and it might explain why people who drink more die younger than people who drink less.
"My report provides another scientific rationale for avoiding excessive alcohol drinking," Ahn told NBC News.
What Drinking Alcohol Does To Your Mouth
Drinking alcohol, the study claims, kills many good bacteria and causes many types of bad ones to flourish in the mouth. Such imbalances contribute to alcohol-related diseases including periodontal disease, head and neck cancer, and digestive tract cancers.
The team tested 1,044 healthy folks between the ages of 55 and 87. Of those, 270 didn't drink, 614 drank moderately, and 160 drank heavily. They all gave the team spit samples along with information about their diet, drinking habits, and lifestyle.
Ahn and her team of researchers tested the samples to check the oral bacteria levels and saw that the drinkers had more Bacteroidales, Actinomyces, and Neisseria — harmful species of bacteria, some of which cause periodontal disease, while others kill off good bacteria. These people also had lower levels of Lactobacillales — beneficial for gum health — compared to those who didn't drink.
The researchers note that while their study included a large number of people, they would still need to study even more to assess microbiome differences among those who consumed only wine, beer, or other types of alcoholic beverages.
What About Wine, Beer, And Others?
The next step, according to Ahn, is to work out the biological mechanisms behind alcohol's effects on the oral microbiome. Also, she stressed that the work is still a long way from determining if blocking or promoting certain changes in the microbiome would lead to healthy bacteria levels such as those found in people who don't drink.
It remains unclear what part of drinking alcohol causes oral bacterial imbalance and whether drinking does kill off good bacteria or simply allows bad ones to flourish. At present, there is merely a link discovered between drinking and oral bacteria, and the researchers would need to perform more experiments to establish cause and effect.