A healthy mouth includes not only clean teeth and hard gums, but also the flora that live in a blood-vessel-rich environment that keeps the organism in constant contact with immune system cells and proteins.

There is growing evidence that this system that appears so separate from the rest of our bodies actually has a large impact on our overall health, Purnima Kumar, a professor of periodontology at Ohio State University, said in a report. and be affected by it. For example, type 2 diabetes has long been known to increase the risk of gum disease. Recent research showing how diabetes affects bacteria in the mouth helps explain how periodontitis treatments that alter oral bacteria also reduce the severity of diabetes itself. In addition, studies have found links between oral microbes and rheumatoid arthritis, cognitive performance, pregnancy, and heart disease, suggesting a link between oral flora and physical health.

The oral microbiome refers to the collection of bacteria that live in our mouths, some helpful and some not. Kumar led and collaborated on recent research that further explains the link between oral health and type 2 diabetes. The study compared the oral microbiota of people with and without type 2 diabetes and their response to nonsurgical treatments for chronic periodontitis.

The team found that periodontitis allows bacteria to control the mixture of microbes and inflammatory molecules in the mouth. Treatment of gum disease eventually restores normal host-microbiome relationships, but at a slower rate in people with diabetes. "Our study concluded that people with diabetes have a different microbiome than people without diabetes," said Kumar. "We know that changing the bacteria in the mouth and restoring them to healthy and friendly bacteria can actually improve your blood sugar control."

While much remains to be learned, the basis for these relationships between the oral microbiome and systemic disease is already clear. Oral bacteria use oxygen to breathe and break down simple molecules of carbohydrates and proteins to sustain life. Something as simple as not brushing your teeth for a few days can trigger a cascade of changes that block oxygen supply and cause microbes to switch to a fermentative state.

"This creates a fermentative environment that produces by-products and toxins that stimulate the immune system," Kumar said. An acute inflammatory response ensues, producing signaling proteins that the bacteria perceive as food.

"Then the ecosystem changed. Organisms that could break down proteins started to grow more, and microbes that could breathe in an oxygen-deficient environment started to grow. The characteristics of the bacteria and, more importantly, the functioning of the immune system changed." .

Inflammation opens the pores between the cells that line the mouth, and blood vessels leak, allowing bacteria that become unhealthy to enter the circulatory system throughout the body. "The body's response to these bacteria is creating inflammation, and these inflammatory products are moving into the bloodstream."

The exact mechanisms underlying the link between the oral microbiome and specific diseases are complex, but the secret to a healthy mouth is no secret at all: Preventing oral disease simply requires maintaining oral hygiene, such as frequent brushing and flossing.