The study explains that tobacco exposure does not just damage teeth and gums but also disrupts the natural balance of oral microbes, a condition known as microbial dysbiosis. (Source: Pexels)
A research by PGIMER professor has found that prolonged use of smokeless tobacco may trigger specific changes in the mouth’s bacterial ecosystem, leading to the growth of microbes capable of breaking down nicotine, a finding that could open new possibilities for tobacco cessation strategies in the future.
Dr Nishant Mehta, associate professor, Unit of Public Health Dentistry, Oral Health Sciences Centre, PGIMER, Chandigarh, was awarded the Best Paper Award for this innovative research focused on tobacco cessation.
Presented at the 29th IAPHD National Conference (NATCON 2025) in Mangaluru, the study was conducted by the Department of Public Health Dentistry and focuses on how repeated nicotine exposure alters the oral microbiome of smokeless tobacco users. Researchers observed that continuous contact with nicotine creates a selective environment in the mouth, encouraging the growth of ‘nicotinophilic’ bacteria, organisms that can use nicotine as a source of energy.
To explore this, saliva samples were collected from smokeless tobacco users and analysed using advanced molecular and microbiological techniques, including 16S rRNA gene sequencing and MALDI-TOF mass spectrometry. These methods allowed researchers to identify microbial shifts at a genetic and species level, while culture-based techniques helped isolate bacteria capable of surviving and growing in nicotine-rich environments.
Once identified, these bacterial strains were cultured in nicotine-containing media, and their ability to degrade nicotine was assessed using UV-visible spectroscopy. The results showed measurable nicotine breakdown, indicating that these microbes actively metabolise the compound rather than merely tolerating its presence.
Researchers say this biological adaptation may hold important implications for tobacco cessation. If nicotine is broken down more rapidly in the oral cavity, it could potentially reduce the intensity and duration of nicotine exposure in the body, which in turn may lower dependence and craving. Over time, this mechanism could be harnessed to support cessation efforts, especially for users of smokeless tobacco products, which remain widely consumed in India.
The study also underlines the need to look beyond conventional approaches to tobacco control, which largely focus on behavioural counselling and pharmacological aids. By understanding how the body’s own microbial systems respond to chronic nicotine exposure, scientists believe it may be possible to develop microbiome-based interventions, such as targeted oral probiotics or adjunct therapies, to assist individuals trying to quit.
Public health experts point out that smokeless tobacco use continues to be a major contributor to oral cancers and periodontal disease in India. In this context, findings that link oral microbial ecology to nicotine metabolism provide a new scientific perspective on addiction biology and prevention.
While researchers caution that further studies and clinical trials are needed before such approaches can be translated into treatment, they describe the findings as an early but promising step towards biologically informed tobacco cessation tools that work in harmony with the body rather than against it.
