In recent years, research has suggested a connection between oral bacteria and Alzheimer’s disease, raising concerns for those with poor dental health.
With nearly 700 species of bacteria inhabiting the human mouth, experts say maintaining good oral hygiene could benefit both heart and brain health.
There is growing evidence suggesting good oral health could help prevent Alzheimer’s disease. One study in the Journal of Alzheimer’s Disease found that people who flossed regularly had a lower risk of developing Alzheimer’s than those who did not.
However, researchers caution there is still limited research. The observational studies do not prove that flossing directly prevents Alzheimer’s disease.
“When you think about it, what is poor gum health, poor dental health? It’s really a bacterial infection,” explained Dr. Celine Gounder, CBS News medical contributor. “When you have chronic infection, chronic inflammation, we know that chronic inflammation increases your risk for heart disease, for cerebrovascular disease, brain disease. It’s really important to control these things.”
According to the Centers for Disease Control and Prevention, about 4 in 10 U.S. adults 30 years or older have some form of periodontal disease.
In addition to causing inflammation, the bacteria associated with gum disease produce enzymes that can be directly toxic to nerves, Gounder said. They also weaken the blood-brain barrier, allowing toxins and other bacteria to enter the brain.
Research shows that these oral bacteria can increase amyloid in the brain — a protein plaque connected with Alzheimer’s disease.
The mouth-to-brain pathway occurs when bacteria from dental problems enter the bloodstream.
“When you have gum disease and dental problems, the bacteria in your mouth are getting into the blood, and from the blood, they can travel anywhere, including the heart and the brain,” Gounder said.
This bacterial spread isn’t a new concern. Before antibiotics became available in the 1800s, dental infections commonly led to heart valve infections and heart failure as bacteria spread through the bloodstream.
While water picks and mouthwash offer some benefits, Gounder emphasized they aren’t sufficient replacements for flossing.
“Water picks are better than nothing, but mouthwash is not a substitute … There is really no replacement for something like flossing,” she said.
The National Institutes of Health identifies several signs of gum disease, including red, swollen, or bleeding gums; pain while chewing; persistent bad breath; and loose or sensitive teeth.
For prevention, the NIH recommends brushing teeth with fluoride toothpaste, flossing regularly, visiting the dentist twice per year, and avoiding smoking.
The recommendation is to floss once daily, preferably before bed. However, people with gingivitis, receding gums, diabetes or heart disease may benefit from flossing at least twice daily.
