A preliminary study found that flossing at least once a week may reduce the risk of stroke

This Simple Hygiene Habit Could Cut Your Risk of Stroke, New Research Reveals Experts explain the finding and share their best practices for oral health

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  • Flossing as little as once a week may reduce the risk of stroke, a new preliminary study found.
  • Flossing helps prevent the buildup of bacteria that can cause inflammation in the body and harm your heart.
  • Experts recommend flossing at least once a day before you brush your teeth and practicing good oral hygiene in general.

Good oral hygiene isn’t just helpful for your teeth—it’s well-established that it can also benefit your cardiovascular health. Now, preliminary study findings suggest that one behavior in particular—flossing—can reduce the risk of stroke, even when done as little as once a week.

In the United States, more than 795,000 people have a stroke each year. It can happen when a clot blocks blood flow to the brain or you have a sudden brain bleed.

The new study shows how “an affordable and easy habit” like flossing may prevent blood clots, lowering the risk of complications like stroke, said William Shutze, MD, a vascular surgeon and secretary of the Society for Vascular Surgery who was not affiliated with the research.

The study, which will be presented at the American Stroke Association's International Stroke Conference 2025 in early February, has not been published in a peer-reviewed journal.

Here’s what researchers found about the relationship between flossing and stroke risk.

Flossing May Protect Against Stroke

The researchers wanted to examine the relationship between oral hygiene habits—flossing, brushing, and dentist visits—and stroke risk because of the global prevalence of oral infection, lead study author Souvik Sen, MD, chair of the department of neurology at Prisma Health Richland Hospital and the University of South Carolina School of Medicine, told Health.

The World Health Organization estimates that oral diseases affect nearly 3.5 billion people worldwide.

Scientists pulled data on more than 6,000 people enrolled in the Atherosclerosis Risk in Communities study, a large-scale examination of cardiovascular disease risk and prevalence in the U.S.

Participants reported their dental floss use frequency, brushing habits, blood pressure, blood sugar, cholesterol, smoking habits, body mass index, education, and dentist visits. 

After 25 years, 434 participants had developed a stroke. Of those strokes, 147 were triggered by larger artery brain clots, 97 occurred due to blood clots that developed in the heart, and 95 resulted from clots in small blood vessels in the brain. A total of 1,291 participants experienced atrial fibrillation (or AFib), which disrupts the normal flow of blood.

Based on this data, the researchers discovered that flossing was associated with a 12% reduced risk of AFib. It was also linked with a respective 22% and 44% lower chance of ischemic stroke, when a blood clot prevents blood flow to the brain, and cardioembolic stroke, when the clot originates in the heart. The connections persisted independently of regular brushing and routine dental visits. 

While flossing once a week was associated with a lower risk of stroke, the study also concluded that the more often you floss, the greater your chance of stroke reduction.

Flossing may reduce stroke risk because it helps to prevent the buildup of bacteria that can occur when food particles remain between teeth, Shutze explained. 

This bacteria can enter the brain or bloodstream, causing inflammation in blood vessels that can trigger blood clots. It can also lead to chronic inflammation associated with gum disease, which is linked with poor cardiovascular health, Shutze said. “This increases the risk of sudden vascular events, strokes, and even heart attacks,” he added. 

Though he acknowledged that more research is needed, Shutz said the findings suggest “another tool” for preventing blood clots and strokes.

However, a key weakness of the study is that it hasn’t been peer-reviewed and published. Additionally, there was no follow-up regarding flossing or other oral hygiene behaviors. The study’s data was also self-reported, which is more prone to inaccuracies.

What to Know About Flossing

If you’re looking to up your flossing game, a good place to start is to figure out which type of floss to try. Options include traditional floss, floss picks, and water flossers, which use a focused stream of water and air to remove food debris, bacteria, and plaque, according to Fatima Khan, DMD, a dentist and co-founder of Riven Oral Care.

The American Academy of Periodontology recommends traditional flossing in conjunction with using a water flosser, Khan told Health

Research shows that it’s better to floss before brushing. You should brush at least twice a day using a fluoride toothpaste, said Randy Kunik, DDS, an orthodontist and founder of Kunik Orthodontics. 

“Spend about two minutes brushing and focus on all surfaces of your teeth, including along the gum line where plaque tends to build up,” Kunik told Health. “Use a soft-bristled toothbrush to avoid damaging your enamel or irritating your gums.”

Beyond brushing and flossing, think about your diet and lifestyle. “Cut back on sugary snacks and drinks because they fuel the bacteria that cause cavities,” Kunik said. “Instead, snack on crunchy fruits and vegetables like apples and carrots—they not only keep your teeth clean but also boost saliva production, which naturally protects your mouth.”

Lastly, don’t skip your regular dental visits: Kunik said that seeing your dentist regularly for cleanings and checkups is key to catching issues early before they become serious.

“At the end of the day, good oral hygiene is simple: brush, floss, eat well, and see your dentist,” Kunik said.

Edited by Health with a background in health, science, and investigative reporting. Previously, she wrote full time about parenting issues for the app Parent Lab. Before that, she worked as a reporter for National Geographic covering wildlife crime and exploitation." tabindex="0" data-inline-tooltip="true"> Jani Hall Jani Hall Jani Hall is a news editor for Health with a background in health, science, and investigative reporting. Previously, she wrote full time about parenting issues for the app Parent Lab. Before that, she worked as a reporter for National Geographic covering wildlife crime and exploitation. learn more

This story originally appeared on: Health News - Author:Elizabeth Yuko, PhD