A landmark study presented at the American Stroke Association’s International Stroke Conference 2025 has put flossing in the spotlight—not just for oral health, but for stroke prevention. The research, which analyzed data from over 6,000 participants, found a strong link between flossing at least once a week and a significantly lower risk of ischemic and cardioembolic strokes.
For dentists, this study reinforces a critical message: oral health is systemic health. This is another reason to double down on patient education and emphasize flossing as more than just a dental hygiene habit—it could be a lifesaving intervention.
How Flossing Lowers Stroke Risk
The study’s findings are impossible to ignore. Regular flossing was associated with a 22% lower risk of ischemic stroke, a 44% lower risk of cardioembolic stroke, and a 12% lower risk of atrial fibrillation (AFib), a major contributor to stroke risk. These benefits held up even when accounting for other oral hygiene habits like brushing and professional dental visits.
Dr. Souvik Sen, the study’s lead author, suggests that flossing reduces systemic inflammation by preventing oral infections—two major culprits in cardiovascular disease and arterial hardening. This research highlights how oral bacteria and inflammation don’t just stay in the mouth. They enter the bloodstream, triggering increased C-reactive protein (CRP) levels, contributing to arterial plaque buildup, and raising the likelihood of blood clots.
For years, periodontal disease has been recognized as a “silent” inflammatory condition. This study adds urgency to that knowledge, making it clear that untreated gingival inflammation can have life-threatening consequences beyond tooth loss.
How to Make This Research Work for Your Patients
Many patients don’t floss because they don’t see the value. This study presents an opportunity to change their mindset. Flossing isn’t just about preventing cavities and gum disease—it’s about protecting the heart and brain. Patients should hear a new message: skipping flossing could increase their risk of stroke.
Instead of the usual lecture, dentists can introduce flossing as a stroke prevention habit. Patients with hypertension, AFib, diabetes, or a history of stroke should be informed that flossing could be as important as taking their prescribed medications. A simple, direct statement—like explaining that new research suggests flossing might lower stroke risk—can be enough to motivate action.
Education should go beyond just recommending flossing. Many patients floss incorrectly, leading to discomfort and bleeding that discourages them from continuing. Demonstrating proper technique during appointments can make a difference. Asking open-ended questions such as, “What’s your flossing routine?” rather than a yes-or-no “Do you floss?” encourages more honest responses and, more importantly, a better conversation.
Patients who struggle with traditional flossing shouldn’t be left without options. Water flossers, interdental brushes, and even prescription-strength antimicrobial rinses can serve as effective alternatives, especially for those with dexterity issues or severe periodontal disease.
The Bigger Picture
If flossing plays a role in reducing systemic inflammation, early detection of periodontal disease becomes even more critical. Dentists should consider tracking inflammation over time using a papillary bleeding index, screening for cardiovascular risk factors in patients with severe periodontal disease, and partnering with physicians to share findings when a patient’s oral health indicates systemic risk.
This research also highlights an opportunity to integrate periodontal health screenings into broader preventive care conversations. Cardiologists and primary care physicians may not be asking patients about their gum health, but dentists can bridge that gap. A routine exam could reveal signs of systemic inflammation long before symptoms of cardiovascular disease appear.
A Simple Step With Major Health Implications
While the study establishes a strong association between flossing and lower stroke risk, it’s important to acknowledge its limitations. The data relies on self-reported flossing habits, which can be inaccurate, and no direct cause-and-effect relationship has been proven yet. Other health behaviors, like diet and exercise, may also play a role in the observed benefits. Still, these limitations don’t diminish the takeaway: flossing is a low-cost, accessible, and effective way to improve both oral and systemic health.
SOURCES: News-Medical, American Heart Association
