What the science says

Most of us know we should brush twice a day. But a growing body of evidence suggests that what happens in your mouth has consequences far beyond your teeth - and that a third daily brush might be worth considering.

At the American Association for the Advancement of Science (AAAS) annual conference in February 2026, a panel of dental and medical researchers made a striking claim: maintaining good oral health may be associated with a reduced risk of more than 50 serious systemic conditions, including dementia and rheumatoid arthritis. That's not a small number, and it's prompting a fresh look at one of the most ordinary habits in our daily routines.

The state of our teeth in the UK

Britain's reputation for bad dental hygiene is something of a cliché, but the data doesn't entirely spare us. The most recent Adult Oral Health Survey found that 41% of UK adults had tooth decay - a substantial rise from 28% in 2009. Almost half of those surveyed said the condition of their teeth had a noticeable impact on their daily life.

Against that backdrop, what researchers are now suggesting carries real weight for a UK audience.

What the experts are saying

The session at AAAS brought together panellists from medical schools across the United States. Professor Alpdogan Kantarci of the University of Minnesota's School of Dentistry told the conference that maintaining teeth in good health may be linked to a lower risk of more than 50 systemic diseases.

He pointed to periodontitis - a serious form of gum disease - as a key part of the picture. When bacteria associated with gum disease enter the bloodstream, they can trigger chronic, body-wide inflammation. That inflammation, in turn, appears to play a role in conditions as varied as rheumatoid arthritis and cognitive decline.

What does “three times a day" actually do?

The recommendation to brush three times a day is about reducing the bacterial biofilm - plaque - that accumulates on teeth throughout the day. The more frequently that biofilm is disrupted, the less opportunity bacteria have to cause gum disease and the resulting inflammatory responses in the wider body.

Professor Kantarci recommended prioritising brushing before bed and after anything sugary, using an electric toothbrush, and not neglecting the tongue, which can harbour just as much bacteria as the teeth themselves.

That said, dental experts note that technique matters as much as frequency. Brushing too vigorously or too soon after eating can damage enamel. A gentle, thorough approach twice a day remains the NHS baseline recommendation - a third brush, done carefully, is considered beneficial for those who want to go further.

A long-running observational study, which followed more than 5,600 older adults over nearly two decades, found that those who did not brush daily had a significantly higher risk of death compared with those who brushed three times a day.

The practical takeaway

None of this requires an overhaul of your routine. The fundamentals haven't changed: brush at least twice a day with fluoride toothpaste, floss daily, don't skip the bedtime brush, and see your dentist regularly. If you want to add a third brush - particularly after lunch or after sugary foods - the evidence suggests it's a worthwhile habit, as long as you brush gently and wait at least 30 minutes after eating.

What this growing body of research does ask us to do is stop treating our teeth as separate from the rest of our health. Your mouth is not an isolated system, and what's happening in your gums may have a bearing on what's happening in your joints, your arteries, and your brain. That's a compelling reason to take the two minutes seriously.