Five surprising health benefits of flossing every morning

Telegraph

23-02-2025

If you brush your teeth morning and night, you probably think your oral health is in pretty good nick. But skipping the extra step of flossing – something only three in 10 people in the UK do daily – could not only leave you at risk of cavities, gum disease and loose teeth, but also chronic health problems such as heart disease, dementia and Type 2 diabetes.
That's because a slimy biofilm is constantly trying to grow on our teeth, explains Morag Powell, a hygienist, dental therapist and lecturer at the University of Plymouth. Brushing your teeth twice a day will remove this substance from the outside and inside of the teeth but not from that hard-to-reach surface between the teeth.
If left to grow and mature in these gaps, the biofilm may eventually trigger gum disease – when the gums become swollen, red, sore and bleed. But the inflammation doesn't stop there – it spreads throughout the rest of the body as well, Powell says.
Some people can't comprehend the links between gum and overall health, says Dr Zoe Brookes, an associate professor of dental education and research at the University of Plymouth. 'But imagine having an infected wound the size of your palm,' she says. 'That's how big the infection is if you've got gum disease. That's going to be affecting your whole body as well.'
'I've spent a lifetime trying to increase awareness of the value and importance of cleaning between the teeth and that's what [all dentists] need to do, so patients are more inclined to do it,' says Powell. Simply flossing for a few minutes a day will not only keep you in your dentists' good books but also help you to dodge an array of health problems. Here's how.
1. Flossing every day will lower your risk of stroke
Flossing just once a week cuts the risk of having a stroke by 44 per cent, according to one recent paper from the University of South Carolina School of Medicine.
Scientists looked at the health records of more than 6,000 people and found that those who flossed weekly were also 12 per cent less likely to develop atrial fibrillation (an irregular heartbeat).
The experts believe their findings may be down to flossing reducing the chance of oral infections and lowering inflammation in the body, which in turn reduces the risk of suffering a stroke and heart problems.
'We know that people who have gum disease are more likely to have cardiovascular disease,' says Brookes.
As well as inflammation in the mouth causing problems for the heart, it could also be that the bacteria that infects unhealthy gums travels to the blood vessels, she notes.
For example, Porphyromonas gingivalis (P. gingivalis), a bacteria that drives gum disease, has been detected in atherosclerotic plaques (a build-up of fats in the artery walls), which suggests a causal link between gum and poor heart health, Brookes explains.
2. It will help protect your brain health
A recent study from the University of Exeter linked the presence of P. gingivalis in the mouth – the bacteria known to fuel gum disease – with a decline in brain function.
The team, who analysed saliva samples from 115 people aged over 50, found that P. gingivalis was more common in people with memory problems. Another family of bacteria linked to poor oral health, called Prevotella was also linked to poor brain health.
Keeping teeth clean – through brushing and flossing – is key for protecting brain health, the scientists concluded.
A separate paper, from a team at Tohoku University in Japan, found people with gum disease and tooth loss had shrinking in the hippocampus (part of the brain critical for memory and learning). The researchers said their findings should encourage people to take better care of their teeth.
3. It reduces your risk of rheumatoid arthritis
Doctors know that rheumatoid arthritis is caused by the immune system going into overdrive and mistakenly attacking the cells that line the joints.
Research suggests that flare-ups in the condition – causing swollen, stiff and painful joints – may be caused by gum disease.
A study from The Rockefeller University suggests that bacteria present in the mouth of patients with gum disease can leak through the gums, into the bloodstream and activate the immune system, causing arthritis symptoms to worsen.
'It does make sense,' says Brookes. 'In rheumatoid arthritis, there's an antibody – citrullinated proteins – that initiates an immune response. There could be an indirect link between gum disease and the activation of this antibody, which then goes on to affect the joints,' she explains.
4. Flossing regularly could lower your pancreatic cancer risk
Maintaining good oral health has been linked to a lower risk of pancreatic cancer.
That's according to a study from NYU Langone Medical Center. Researchers compared saliva samples from 720 people, half of whom later develop pancreatic cancer. Results showed that those with high levels of P. gingivalis had a 59 per cent higher risk of developing the cancer.
Explaining their findings, the scientist suggested that the inflammation caused by P. gingivalis may have caused inflammation in the pancreas which led to cancer, or that the bacteria may have been a signal of cancer-causing inflammation.
'The links between cancer and gum disease is a more controversial area,' Brookes notes. There have been some individual studies showing a connection but association has not been the subject of a systemic review, she says.
5. Slashes Type 2 diabetes risk
'Poor oral health has been linked with Type 2 diabetes,' Brookes notes. That's because having gum disease is known to increase blood sugar levels, which in turn increases the risk of developing type 2 diabetes.
Additionally, gum disease triggers inflammation throughout the body, which is another risk factor for the condition.
People who have type 2 diabetes are also at greater risk of gum disease, as they have a more aggressive inflammatory response to the bacteria in their mouth, she says. 'There's a bit of a chicken and egg – gum disease might cause diabetes but diabetes actually might make gum disease worse as well.'
How to floss and use interdental brushes
Flossing