Lungs Can Get Affected Due to Mouth Bacteria

Oral Bacteria and Your Lungs

New research published in the journal mSphere has examined the effect of poor dental hygiene on the respiratory health of elderly Japanese people. The study brings into focus how tongue microbiota is vital for respiratory health and was undertaken by a team of Japanese-based scientists with the Kyushu University, Fukuoka.

The study’s senior author was Dr. Yoshihisa Yamashita, who is associated with the Division of Oral Health, Growth, and Development in Kyushu University’s Faculty of Dental Science. Along with his colleagues, Dr. Yamashita explained in their paper that oral microbiota is crucially essential for general health as the bacteria we ingest can impact all aspects of our health.

Bacteria in our tongue microbiota can reach our guts. Moreover, seniors are more likely to inhale some of these microorganisms. Medical issues such as problems in swallowing and cough reflux may lead to the elderly accidentally inhaling bacteria, which can cause pulmonary infections such as pneumonia.

Apart from this study, Medical News Today has also reported several similar studies highlighting the link between gut microbiota and diseases such as cancer, obesity, heart conditions, depression, and anxiety.

What Links Oral Health and Pneumonia?

While investigating the impact of dental hygiene on older adults, Dr. Yamashita and his team analyzed the tongue microbiota composition of 506 seniors aged between 70–80 years. The seniors, all community-dwelling, were residents of the Japanese city Hisayama. The seniors had received a dental exam in 2016.

Using an advanced genomic sequencing technique called 16S rRNA genetic sequencing, the researchers examined the composition and density of the microbiota in the seniors. The primary bacteria classified included Streptococcus salivarius, Veillonella atypica, Prevotella histicola, and Streptococcus parasanguinis.

Researchers say previous studies have associated the microorganisms with greater risk of death due to pneumonia. The bacteria were primarily found in seniors with more cavities, fewer teeth, plaque, and those wore dentures.

“These results suggest that elderly adults with poorer oral health swallow a more dysbiotic microbiota formed on the tongue,” say the authors of study.

Dysbiosis indicates a microbial imbalance in the tongue or the gut. Microbial imbalance in the gut is associated with diseases involving the immune system such as inflammatory bowel disease. An imbalance in the tongue microbiota in older adults has been linked with a higher risk of pneumonia-related death in past studies.

Dr. Yamashita, while summarizing the findings, said, “Fewer teeth, poorer dental hygiene, and more dental caries (cavities) experience are closely related to dysbiotic shift in the tongue microbiota composition, which might be harmful to the respiratory health of elderly adults with swallowing problems,” reported Medical News Today.

Overall, the study emphasizes dental health: “Careful attention should be given to the tongue microbiota status in elderly adults with poorer dental conditions,” said Dr. Yamashita. Statists support the findings of the study. In 2015, in the US, more than 540,000 seniors were admitted in the hospital and diagnosed with pneumonia, and about 52,000 people lost their lives due to the lung condition.