Can good dental hygiene protect your brain?
Posted on June 5, 2025 in Healthy You
You may have heard that good oral health supports your overall health, too. Studies have shown a strong link between oral health and diabetes and heart disease, but research has also uncovered a possible connection between oral health and brain health. In fact, one study has found that people who maintain healthy teeth and gums through daily brushing and flossing have reduced risk of Alzheimer’s disease.
A large 2020 study conducted by scientists from the National Institute on Aging (NIA) and published in the Journal of Alzheimer’s Disease found that the bacteria that causes gum disease are associated with the development of Alzheimer's disease and other forms of dementia.1
How mouth bacteria affects the brain
Gum disease, which is also called periodontal disease, is caused by harmful bacteria that can infect and inflame the gums. Without treatment, gum disease often leads to symptoms like bleeding gums, loose teeth and even tooth loss in its most severe form.
Your mouth contains hundreds of bacteria species, and some of them are harmful and can lead to gum disease. One of the primary bacteria that causes gum disease is Porphyromonas gingivalis (or P. gingivalis). This bacteria and the inflammation it produces can move from your mouth to other parts of your body by traveling through your bloodstream. This is how the bacteria in your mouth can end up in your brain, triggering changes that may contribute to Alzheimer’s disease.2
More about the study
The NIA study analyzed survey data on over 6,000 participants that had received dental exams and blood tests related to gum disease. Researchers reviewed the dental records for and blood tests and found that people who had signs of gum disease and higher levels of antibodies against P. gingivalis were more likely to develop Alzheimer's disease or other forms of dementia over a follow-up period of up to 26 years.2
Although this research highlights a connection between gum disease and dementia, it's important to know that it does not mean there’s a direct cause-and-effect relationship. So, scientists cannot say that gum disease directly causes dementia based on these findings.
Taking care of your oral health goes beyond your mouth
More research is needed to determine whether preventing or treating gum disease can directly reduce your risk of developing dementia, but maintaining good oral hygiene is a great way to keep your mouth, body and mind healthy. Here’s how you do that:
- Schedule regular dental check-ups: See your dentist twice a year for deep cleanings and to detect any early signs of gum disease or other oral health issues.
- Brush your teeth twice daily: Use fluoride toothpaste to remove plaque and prevent tooth decay.
- Floss daily: Flossing helps remove food particles and plaque from areas your toothbrush might miss, such as between the teeth and under the gumline.
- Eat a balanced diet: Limit sugary foods and beverages that feed harmful bacteria in your mouth. Instead, fill your plate with calcium-rich dairy, fruits, vegetables, lean protein and whole grains.
- Quit smoking: Smoking and other tobacco use can increase the risk of gum disease. Smoking is also a risk factor for Alzheimer’s disease. Quitting will improve all areas of your health.
Making these habits part of your lifestyle not only keeps your teeth and mouth healthy but also supports your total well-being. Scientists still need to dig deeper to understand the connection between gum disease and dementia risk, but taking proactive steps now to care for your teeth and gums is a smart investment in your long-term health.
SOURCES:
National Institute on Aging
Science.org
REFERENCES:
1. National Library of Medicine
2. National Institute on Aging