Why You Really Need to Floss Your Teeth

Could flossing and brushing help prevent Alzheimer's?. Rido/Shutterstock

You're a smart person who knows how important it is to take care of your health. You eat lots of vegetables, get plenty of sleep, exercise and avoid tobacco products. But when you brush your teeth, how likely are you to floss on a regular basis? It's not incredibly hard and it doesn't usually hurt. But for some reason, this hygiene habit isn't one that all of us undertake with true commitment.

Results of recent research might motivate you to start a real relationship with floss.

In a study coordinated by Cortexyme, a pharmaceutical firm in San Francisco, researchers found a link behind the key pathogen in chronic periodontitis (gum disease) and Alzheimer's. They discovered gingipains — the toxic enzymes secreted by the bacteria Porphyromonas gingivalis — in 96% of the brain samples of Alzheimer's patients they studied.

It's not the first time researchers have studied a possible connection between bacteria and Alzheimer's disease. But when the pathogen has been found in the brains of patients who died with Alzheimer's disease, researchers weren't sure if the bacteria caused the disease or entered the brain because it was weakened by the condition, New Scientist reports.

In the Cortexyme study, which was published in Science Advances, researchers took a second step. They infected mice orally with the bacteria and found that the mice developed neural damage in the parts of the brain commonly associated with Alzheimer's.

Finding an answer

Porphyromonas gingivalis
Porphyromonas gingivalis may be at the root of Alzheimer's disease. Kateryna Kon/Shutterstock

The researchers think they may be on the right path to uncovering a true cause for Alzheimer's.

"Infectious agents have been implicated in the development and progression of Alzheimer's disease before, but the evidence of causation hasn't been convincing," said lead author and Cortexyme co-founder Stephen Dominy, M.D., in a EurekAlert press release.

"Now, for the first time, we have solid evidence connecting the intracellular, Gram-negative pathogen, Pg, and Alzheimer's pathogenesis while also demonstrating the potential for a class of small molecule therapies to change the trajectory of disease."

Interestingly, the researchers also found gingipains in the brains of some deceased subjects who had never been diagnosed with Alzheimer's.

"That's important, because while P. gingivalis and the disease have been linked before, it's never been known — to put it simply — whether gum disease causes Alzheimer's, or whether dementia leads to poor oral care," Peter Dockrill writes in Science Alert. "The fact that low levels of gingipains were evident even in people who were never diagnosed with Alzheimer's could be a smoking gun — suggesting they might have developed the condition if they had lived longer."

What you can do

This research shows yet another reason to take care of your teeth and gums. In its mildest form, gum disease is gingivitis, where gums are red and swollen and bleed easily. It's caused when bacteria in plaque builds up between the gums and the teeth. Your gums could be red, swollen and bleed easily. If it continues unchecked, it can become periodontitis, which is often characterized by abscesses and tooth loss, reports the American Dental Association.

To keep your mouth healthy:

Brush your teeth. Brush after meals to remove food and plaque. Don't forget to brush your tongue.

Floss. Floss at least once a day to remove plaque and food between your teeth and along your gumline, where your toothbrush can't reach.

Use mouthwash. Mouthwash can lower plaque and rinse away any leftover food particles that brushing and flossing missed.

See your dentist. Have your teeth cleaned professionally at least once or twice a year. Early stages of gum disease can be reversed by a cleaning at your dentist's office.

View Article Sources
  1. "New Survey Highlights 'Unusual' Flossing Habits." American Dental Association.

  2. Dominy, Stephen S., et al. “Porphyromonas gingivalis in Alzheimer’s Disease Brains: Evidence for Disease Causation and Treatment with Small-Molecule Inhibitors.” Science Advances, vol. 5, no. 1, 2019, p. eaau3333., doi:10.1126/sciadv.aau3333

  3. Beydoun, May A., et al. “Clinical and Bacterial Markers of Periodontitis and Their Association with Incident All-Cause and Alzheimer’s Disease Dementia in a Large National Survey.” Journal of Alzheimer’s Disease: JAD, vol. 75, no. 1, 2020, pp. 157–72., doi:10.3233/JAD-200064

  4. "Home Oral Care." American Dental Association (ADA).

  5. "Mouthwash (Mouthrinse)." American Dental Association (ADA).