How you brush your teeth could be linked to dementia risk

Multiple studies have a established a connection between oral care and cognitive wellbeing

The way you care for your teeth may have an impact on your cognitive abilities later in life, according to a growing body of research.

Most recently, a study published in July in the journal Neurology found that if people don’t have all their teeth, or if they have a gum infection called periodontitis, parts of their brain may be more likely to atrophy—or break down—as they age.

A separate study published in 2020 looked at data from humans and rats and also found that “poor oral health conditions”—including missing teeth—may be risk factors for cognitive decline; while an analysis published as early as 2007 found a low number of teeth increases the risk of dementia. The report from 2007 went so far as to say that having fewer teeth “may be [a predictor] of dementia late in life”.

Though multiple reports have established a connection between oral health and cognitive decline, researchers say future studies need to investigate the mechanism by which the former affects the latter.

However, researchers do have theories as to why the two are related. Some have posited that when a person loses teeth, their eating habits change and, as a result, they don’t get the nutrients they need. “A lack of nutrients, such as B vitamins, may have an impact on cognition due to changes in eating habits caused by missing teeth,” a 2023 paper states.

Another theory is that the inflammation caused by periodontitis may be to blame, as inflammation has been linked to the risk of dementia and cognitive decline.

Regardless of the details of the connection, experts say it is one more reason to practise good oral health, especially as you age.

Ideally, you should be brushing your teeth at least twice a day with fluoride toothpaste, per the Mayo Clinic. Each time you brush, you should do so for at least two minutes, according to the American Dental Association. It can be helpful for some to set a timer while they’re brushing to make sure they brush long enough.

Brushing helps prevent peritonitis, as does flossing daily and getting regular dental checkups.

Good oral health has been linked to better cognitive health later in life in a growing body of evidence (Getty Images)

If you’re experiencing symptoms of the condition, you should also seek medical care. Warning signs include puffy or swollen gums; bright red, dark red, or dark purple gums; gums that bleed easily or feel tender when touched; spitting out blood after brushing or flossing; noticing pink on your toothbrush after brushing; bad breath; pus between the teeth and gums; loss of teeth or lose teeth; pain when chewing; new spaces developing between the teeth; gums that pull back from the teeth, making them look longer than they should (this is also called receding gums); and a change in the way your teeth fit together when you bite down, per the Mayo Clinic

You should make an appointment with a dentist as soon as possible if you notice any of the above symptoms since getting treatment immediately minimises the chances of damage caused by periodontitis.

Aside from cognitive decline, periodontitis has been linked to bloodstream infections, respiratory disease, rheumatoid arthritis, coronary artery disease, blood sugar issues, diabetes, and even preterm birth and low birth weight.

These and the growing number of reports linking the condition to poor cognitive health later in life make the case for establishing good oral health habits early on, experts say. Per the Mayo Clinic, “The best way to prevent periodontitis is to get into the habit of taking good care of your mouth and teeth. Start this routine at a young age and keep it throughout life.”