Regular flossing may do more than just improve oral hygiene—it could also benefit heart health. According to early findings from a recent study, individuals who floss regularly had a lower likelihood of developing atrial fibrillation (irregular heartbeat), a condition that increases the risk of stroke and other cardiovascular issues.
Key Takeaways:
- Flossing at least once a week may contribute to a reduced risk of stroke and atrial fibrillation, as suggested by preliminary research findings.
- The study also associated flossing with overall better health markers, such as improved blood pressure, healthier cholesterol levels, and a decreased likelihood of developing diabetes.
- Though the exact mechanism remains unclear, researchers believe flossing could help protect heart and brain health by minimizing inflammation.
Flossing: A Simple Habit with Potential Heart and Brain Benefits
Maintaining oral hygiene may do more than just protect your teeth—it could also play a role in reducing the risk of serious cardiovascular conditions. According to a preliminary study set to be presented at the American Stroke Association’s International Stroke Conference 2025 in Los Angeles, flossing at least once a week might lower the likelihood of both stroke and atrial fibrillation (afib), an irregular heart rhythm linked to heart failure and stroke.
“Flossing was also linked to better overall health, including lower blood pressure, healthier cholesterol levels, and lower chances of diabetes,” says Souvik Sen, MD, the study’s lead author, chair of the neurology department at the University of South Carolina School of Medicine, and a neurologist at Prisma Health in Columbia, South Carolina.
Exploring the Link Between Oral Hygiene and Cardiovascular Health
The researchers aimed to determine which aspect of oral hygiene—flossing, brushing, or regular dental visits—had the most significant impact on stroke prevention. The study tracked approximately 6,300 participants, with about 65% reporting that they flossed.
Participants completed detailed questionnaires regarding their oral hygiene habits, dental care frequency, and overall health status, including factors such as high blood pressure, diabetes, cholesterol levels, smoking history, and body mass index (BMI). Over a 25-year follow-up period, researchers observed:
- 434 cases of stroke, including:
- 147 due to larger artery brain clots
- 97 resulting from heart-related clots
- 95 linked to small artery hardening
- 1,300 cases of atrial fibrillation (afib), a condition that disrupts the heart’s rhythm, increasing the risk of stroke and heart failure.
Flossing Benefits May Extend Beyond Just Oral Health
Although the study is still awaiting peer review, preliminary findings suggest that flossing at least once a week was associated with significant cardiovascular benefits, including:
- A 21% lower risk of ischemic stroke, the most common type of stroke caused by blood clots blocking brain arteries.
- A 44% reduced risk of cardioembolic stroke, where blood clots form in the heart and travel to the brain.
- A 12% lower risk of atrial fibrillation (afib), a condition that can increase the likelihood of stroke and other cardiovascular complications.
Interestingly, these benefits were observed regardless of whether individuals regularly brushed their teeth or sought professional dental care, suggesting that flossing alone might play a unique role in lowering these health risks.
Understanding How Flossing May Protect the Heart and Brain
This study builds upon previous research highlighting the relationship between oral health and cardiovascular conditions. The American Heart Association (AHA) has long recommended regular dental checkups as part of an overall heart-healthy lifestyle. However, the new findings bring fresh insight, particularly regarding the link between flossing and a reduced risk of afib.
The prevalence of afib is much higher than previously estimated, with a recent study suggesting that at least 10.5 million Americans have the condition. Given that afib increases the risk of stroke, heart failure, and other serious health problems, understanding its prevention is critical.
So, why might flossing help lower afib risk? Dr. Sen explains that flossing reduces oral infections, including gum disease and cavities, which in turn lowers systemic inflammation. Inflammation is believed to play a key role in triggering and exacerbating afib through several mechanisms:
- Increased inflammation and oxidative stress contribute to atrial fibrosis (scarring) and heart remodeling, which can disrupt the normal electrical activity of the heart.
- Inflammatory stress affects heart rate variability, increasing susceptibility to irregular rhythms like afib.
- Inflammation damages the blood vessel lining, making it easier for blood clots to form, thereby raising stroke risk.
Moreover, inflammation is closely linked to atherosclerosis, a condition characterized by hardening and narrowing of the arteries, which can contribute to both stroke and heart disease. By helping to control inflammation, flossing may serve as a simple yet effective preventive measure.
Does Flossing Directly Reduce Stroke Risk?
Despite these promising findings, experts caution against drawing definitive conclusions about causation. The study was observational, meaning it gathered data based on participants’ existing flossing habits rather than conducting controlled experiments.
“Flossing is great for your teeth, but linking it directly to stroke prevention is tricky,” says Harlan Krumholz, MD, a professor of medicine and director of the Yale Center for Outcomes Research and Evaluation in New Haven, Connecticut, who was not involved in the study.
“People who floss regularly often take better care of their health in general—eating well, exercising, and keeping up with medical care—so it’s hard to say whether flossing itself lowers stroke risk, or if it’s just part of an overall healthy lifestyle,” he explains. “Studies like this are interesting, but we need to know more to prove cause and effect.”
Nonetheless, the study aligns with growing evidence that poor oral health is linked to systemic diseases, including cardiovascular disease, diabetes, and even cognitive decline.
The Global Impact of Poor Oral Health
Oral diseases remain a major public health concern worldwide. A recent global health report found that in 2022, oral diseases affected approximately 3.5 billion people, making them one of the most widespread health conditions globally.
In the United States, nearly 4 in 10 adults have some form of periodontal (gum) disease, such as gingivitis and periodontitis. Among adults over 65 years old, this figure rises to 6 out of 10. Given these statistics, promoting good oral hygiene—such as flossing—could have significant public health benefits.
Bottom Line: A Simple, Affordable Way to Improve Health
Although further research is needed to establish a direct causal link between flossing and reduced stroke risk, the findings suggest that this simple habit may have broader health benefits than previously thought.
“Flossing isn’t just good for your teeth—it might help protect your heart and brain, too,” says Dr. Sen.
“It’s a simple, affordable way to improve oral health and possibly prevent serious heart and brain conditions,” he adds.
While flossing alone may not be a miracle cure for cardiovascular disease, incorporating it into a routine alongside brushing, regular dental checkups, a healthy diet, and exercise could contribute to long-term well-being.