The Forgotten Link Between Poor Dental Hygiene and Alzheimer’s Disease

by DailyHealthPost Editorial

We’ve always known that tooth problems are often closely related to neurological issues or at the very least – to more pronounced pain. There’s a reason why toothaches are more annoying than similar problems elsewhere in our bodies – they are simply closer to our central nervous system. 

Is there a way for tooth problems and diseases to actually “transfer” to the brain, however? It turns out that yes, the Porphyromonas gingivalis or just P. gingivalis which is the leading cause of both gingivitis and periodontitis may have a role to play in the development of Alzheimer’s as well.

What’s the connection?

Thanks to a recent study from the University of Bergen we now know that gingivitis plays a big role in whether and when you’ll develop Alzheimer’s disease. 


Piotr Mydel at Broegelmanns Research Laboratory, Department of Clinical Science, University of Bergen (UiB), a researcher on the project explains that they’ve discovered irrefutable DNA-based proof about how the P. gingivalis bacteria can move from the mouth to the brain.

Once it gets to the brain, the bacteria start producing a protein which leads to memory loss and in turn – to Alzheimer’s. 

Mydel points out, however, that the bacteria is not directly responsible for Alzheimer’s disease, but it is a major contributing factor. The presence of the bacteria in our brains substantially increases the risk of developing the disease. It’s also been shown to speed up its progression.

Of the 53 people the Bergen scientists tested, 96% had signs of P. gingivalis’ proteins and enzymes in their brains. 

Not the first study to point to gingivitis

Even though Mydel’s team is adamant about their discovery, in science things must always be fact-checked and peer-reviewed. That’s why it’s important to point out that this isn’t actually the first research to point out a connection between gingivitis and Alzheimer’s. 

In 2019, scientists from the University of Louisville School of Dentistry and Jagiellonian University in Krakow, Poland also looked into the connection. They compared samples of deceased people both with and without Alzheimer’s of relatively similar ages of death and general health. The scientists determined that the P. gingivalis bacteria was much more common in the bodies of former Alzheimer’s patients.  


Fortunately, this also gives some insight into how we can delay or prevent Alzheimer’s – by taking an even better care of our dental hygiene. 

Key facts about Gingivitis

So, what do we need to know about P. gingivalis both in relation to Alzheimer’s and in general? Here’s a quick summary.

  • The bacteria Porphyromonas gingivalis or P.gingivalis is one of the main causes of infections in the gums.
  • The bacteria can easily move to the brain if left unchecked where it can damage our nerve cells.
  • About 50% of the population have this bacteria in one form or another.
  • People typically contract the bacteria in their developmental teen years. From then, it’s a matter of how well we maintain our dental hygiene to prevent the spread of the bacteria. 
  • About 10% of people with P. gingivalis develop serious gum disease, loose teeth, or have an increased risk of Alzheimer´s disease.
  • P. gingivalis has also been linked to rheumatism, COPD, and esophageal cancer.

Medicine is on the way

There are more positive developments from this discovery, not just the realization of how important it is to brush our teeth. The Bergen scientists have also started working on a new medicine that can help prevent the disastrous effects of the bacteria on our brains. If the drug pans out, it can help slow or prevent the development of Alzheimer’s altogether.

“We have managed to develop a drug that blocks the harmful enzymes from the bacteria, postponing the development of Alzheimer´s. We are planning to test this drug later this year,” said Piotr Mydel.

In conclusion

It sounds silly to just recommend brushing your teeth and visiting a dentist but it’s clear that it’s important for brain health.

With that in mind, here are some extra tips if you’re worried about developing Alzheimer’s:

  • Maintain excellent dental hygiene. This includes brushing your teeth, using dental floss and mouthwash, as well as going for routine dental checkups at least once per year.
  • Eat well. Maintaining a good diet is essential for preventing or slowing down Alzheimer’s as the Nation Institute of Aging explains here.
  • Exercise more. Our brains require a constant supply of blood and oxygen to stay healthy and that’s best achieved by regular exercises. 
  • Keep your heart healthy. For the same reason as above, having good cardiovascular health is crucial for delaying or avoiding Alzheimer’s. Plus, it’s vital for a lot of different reasons. 
  • Improve your sleep. Our sleep is the brain’s time for self-maintenance and healing. Suffering from sleep apnea, insomnia, or just not getting enough sleep are all closely related to developing cognitive problems.