Smoking modifies the bacteria in your mouth… in a bad way. Yet another reason to quit smoking: it changes the oral microbiome according to a new study published in the International Society for Microbial Ecology Journal.
The mouth contains hundreds of species of bacteria that are needed for the proper functioning of the human body. It is known that imbalances in microbial populations in the gut are linked with cancers, and previous research has also shown that smoking is associated with many types of oral cancers. Could this common link be due to smoking-related bacterial community differences? Researchers from the NYU Langone Medical Center and its Laura and Isaac Perlmutter Cancer Center attempt to answer this question.
The research is the first of its kind to demonstrate the effect of smoking on the oral microbiome, points out senior author, epidemiologist Jiyoung Ahn.
The mouthwash samples of 1,204 men and women were analysed. 112 of them were smokers, while 571 were former smokers, and the remaining ones had never smoked. When genetic and statistical tests were used to differentiate among the thousands of bacteria in the mouth of each of them, it was found that the oral microbiome of smokers was significantly different from that of the two other groups. Over 150 bacterial species had increased in growth for smokers, and another 70 had decreased in growth: the bacteria that were in reduced numbers were found to be those known to break down toxic chemicals in tobacco; on the other hand, the increased bacteria are those associated with tooth decay.
Fortunately, though, the oral microbiome of smokers reverts to what it was, following giving up the bad habit. Former smokers who had stopped for at least 10 years had the same microbial balance as non-smokers.
Does this indicate that smoking causes diseases by messing with the gut bacteria populations? Ahn explains that more experiments need to be done to confirm whether the said changes affect the defenses of the body negatively such that they are unable to fight cancer-causing chemicals in tobacco smoke. Nothing is proved yet.