Woman brushing teeth

A woman brushing her teeth (© Wayhome Studio - stock.adobe.com)

ANN ARBOR, Mich. — Inflammatory bowel disease (IBD) affects about three million people in the United States. An imbalance in the gut’s microbiome can be the cause of painful, and sometimes chronic, stomach conditions. A new study suggests trouble in your gut may actually start with trouble in your mouth. Researchers from the University of Michigan say poor oral hygiene can make a person’s IBD worse.

The study reveals two possible ways bacteria in a patient’s mouth travels to the gut and causes more inflammation. Researcher Nobuhiko Kamada says there is growing evidence that people with IBD have an overgrowth of foreign bacteria in their gut. That bacteria, Kamada says, typically starts within one’s mouth.

“I decided to approach the dental school to ask the question, does oral disease affect the severity of gastrointestinal diseases?” the assistant professor of internal medicine says in a university release.

Gum disease doesn’t stay in your mouth

Previous research shows that not taking care of your teeth and gums leads to more than just cavities. Scientists link poor oral health to heart disease and diabetes in some cases.

Published in the journal Cell, Kamada and his team studied the two routes gut inflammation that may be worsened in mice with gum disease.

In one possible route, researchers say periodontitis (gum disease) creates an unhealthy imbalance in the mouth’s microbiome. That bacteria causes both inflammation and disease which then travels down into the gut. This particular process doesn’t trigger IBD, researchers say, but it does aggravate the symptoms of mice with colon inflammation.

“In mice with IBD, the healthy gut bacteria are disrupted, weakening their ability to resist disease-causing bacteria from the mouth,” explains Kamada.

The study adds those mice experienced increased weight loss and more disease activity in their bodies.

Your T cells and IBD

In the other route, the team says periodontitis actually causes the body’s own immune system to damage the gut.

Gum disease causes the immune system to react, sending T cells to the mouth to fight infection. In a healthy gut, inflammatory and regulatory T cells work in harmony and know how to tolerate local bacteria.

Researchers say gum disease triggers mostly inflammatory T cells to react. Those cells eventually travel to the gut and throw off the natural balance, causing diseases to worsen.

Oral hygiene is the best medicine

The authors the study may lead to new IBD treatments focusing on mouth bacteria. Current medications don’t always do the job.

“This exacerbation of gut inflammation driven by oral organisms that migrate to the gut has important ramifications in emphasizing to patients the critical need to promote oral health as a part of total body health and wellbeing,” says William Giannobile from the UM School of Dentistry.

Inflammatory bowel disease includes conditions like Crohn’s disease and ulcerative colitis. Depending on the illness, patients can experience abdominal pain, bloating, diarrhea, and fever. Severe cases can damage the gastrointestinal tract and eventually lead to surgery.

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About Chris Melore

Chris Melore has been a writer, researcher, editor, and producer in the New York-area since 2006. He won a local Emmy award for his work in sports television in 2011.

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