People who drink the most alcohol carry about 10 more types of oral bacteria than nondrinkers, according to new research, and some of those extra species are linked to gum disease.
The mouth is a living ecosystem made up of hundreds of species of bacteria that constantly interact with one another and with the immune system, Arthur Glosman, a cosmetic dentist in Beverly Hills, California, who was not involved in the study, told The Epoch Times.
“Health is not determined by the presence or absence of one organism,” he noted. “It is determined by balance.”
Alcohol Encourages Bacteria Linked to Gum Disease
Researchers used questionnaires to track people’s beverage habits and sampled their oral microbiome using mouthwash. These samples were then analyzed using genetic sequencing.
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Compared with drinking tea, coffee, and sugary drinks, alcohol consumption was the only category associated with overall changes in the variety and composition of oral bacteria. For example, people in the group with the highest alcohol consumption had about 10 more types of bacteria compared with nondrinkers.
Heavy drinkers were more likely to carry Megasphaera and Peptostreptococcus, two types of bacteria associated with gum disease, and less likely to carry Lautropia, a bacterium that is usually found in healthy mouths but tends to decrease in people with dental issues.
While an increase in certain bacterial species may indicate a higher risk of developing gum disease, “it is important to consider this risk relative to the other factors,” Steve Mascarin, a dentist at Halton Village Dental in Toronto, who was not involved in the study, told The Epoch Times. These factors include poor oral hygiene, smoking, diabetes, other periodontal diseases, and insufficient dental care.
Mascarin emphasized that gum disease develops in response to inflammation and is “due to a community of bacteria rather than isolated bacterial pathogens.”
Ambereen Fatima, a dentist in Marlborough, Massachusetts, who was not involved in the study, told The Epoch Times that Peptostreptococcus is well-established in dentistry. It shows up in deep gum pockets and infected teeth and has been linked to gum disease for decades. Megasphaera, she said, is a newer, less understood name that “points at a neighborhood we already know is rough, rather than naming a new culprit.”
Fatima cautioned that the habit she’d watch for is drinking before bed, since alcohol dries the mouth and saliva is a natural defense that helps rinse the mouth and buffer acids.
“Wine and most mixers are acidic and sugary on top of that,” Fatima said. “When I find erosion and a persistently dry mouth, a nightly drink or two (before bed) is often somewhere in the history.”
Oral Health Influenced by Many Factors
Mascarin added that gum disease develops from a broader imbalance in the mouth’s bacterial community rather than from any single organism—and that factors like poor oral hygiene, smoking, and diabetes remain more established risk factors than any one beverage.
The study shows an association between drinking and bacterial changes, not proof that alcohol causes them. That distinction matters because heavy drinkers also tend to smoke more and brush their teeth less often—habits that independently affect oral health.
While alcohol intake explained only a small part of the differences in bacterial communities, the study authors noted that alcohol was the most influential among the beverages studied.
Other beverages appeared to have little to no effect.
Glosman said the mouth’s bacterial balance shifts gradually in response to diet, sleep, medication, and stress. When that balance remains disrupted for years, chronic inflammation can follow, raising the risk of gum disease and potentially affecting health elsewhere in the body.
“The mouth is incredibly dynamic,” Glosman said, adding that every meal, every drink, every night’s sleep, every medication, and even our stress levels influence this ecosystem.
Regular dental visits, he added, can help catch small changes before they become larger problems by checking not just for cavities, but also for gum health, saliva quality, and signs of inflammation.
“Patients not only keep their teeth longer, but they often breathe better, function better, and in many cases enjoy better overall health,” Glosman said. “The mouth is not separate from the body. It is one of the most accessible windows into it.”
