Gargling to get rid of “bad” bacteria in type 2 diabetes

In addition to causing bad breath, there is growing evidence that ongoing inflammation in the mouth, such as that seen in periodontal disease, is associated with serious diseases such as Alzheimer’s disease and type 2 diabetes. Now researchers at Osaka University have identified a simple way to combat the bacterial cause.

In a study published this month, scientific report, researchers reported that when patients with type 2 diabetes gargled with an antiseptic mouthwash, the number of periodontitis-associated bacteria decreased. Additionally, some patients with reduced bacteria had much better control of their blood sugar levels, suggesting potential clinical applications in the future.

“There are three types of highly virulent bacteria that are associated with periodontitis, a disease of the tissues surrounding the teeth,” explains Saaya Matayoshi, lead author of the study. “We want to see if we can reduce these three species, Porphyromonas gingivalis, Treponema herbifolia, and Forsythia tannerella, in patients with type 2 diabetes using a mouthwash containing the antiseptic chlorhexidine gluconate. I decided to check it out.”

To do this, the researchers collected saliva and blood samples from 173 patients monthly or bimonthly over a one-year period. Researchers used saliva to check for the presence of three types of bacteria, and blood samples to measure her HbA1c levels as a marker of blood sugar control.

Importantly, for the first six months of the study, patients gargled with water, but for the second six months they gargled with antiseptic mouthwash. In this way, the research team was able to see whether gargling itself was effective at reducing bacteria, or whether mouthwash was more effective.

“We were not surprised to see that gargling with water had no effect on bacterial species or HbA1c levels,” explains Kazuhiko Nakano, senior author of the study. “But when patients switched to mouthwash, provided they gargled at least twice a day, we saw an overall reduction in bacterial species.”

The researchers also found that while there was no overall change in HbA1c levels when patients gargled with antiseptic mouthwash, there appeared to be wide variation in individual responses. For example, when the group was divided into younger and older patients, the younger patients had significantly fewer bacterial species and significantly better blood sugar control with mouthwash compared to water.

Given that poor oral hygiene is associated with serious diseases, simple ways to improve oral hygiene have important implications. If researchers can identify patients who are more likely to respond well to antiseptic mouthwashes, this easy-to-use treatment could help patients with periodontitis-related diseases such as diabetes, dementia, cardiovascular disease, and respiratory tract infections. People’s lives can be improved.