Using dental floss regularly could reduce the risk of stroke, according to the American Health Association.
The AHA 2025 Heart Disease and Stroke Statistics estimated that over 12 million patients may develop atrial fibrillation by 2030 in the United States. Previous studies have uncovered a potential correlation between oral infections, incident strokes, and atrial fibrillation. Nonetheless, the relationship between oral hygiene practices and strokes has been poorly studied.
In the study, the preliminary findings of which were presented at the American Stroke Association International Stroke Conference 2025, researchers asked 6,278 dentate participants without a history of stroke to complete a structured questionnaire regarding their age; gender; race; smoking status; body mass index; education level; brushing habits; dental visits; and preexisting conditions, including high blood pressure, diabetes, and high cholesterol.
The researchers noted that 65% (n = 4,092) of the respondents reported regular dental flossing. After a follow-up of 25 years, they identified 1,291 cases of atrial fibrillation as well as 434 incidents of stroke—147 were larger artery brain clots, 97 were heart-driven clots, and 95 were hardening of the smaller arteries.
The researchers discovered that compared with those who didn’t floss, the participants who did floss were 22% less likely to experience ischemic stroke, 44% less likely to experience cardioembolic stroke, and 12% less likely to experience atrial fibrillation. However, regular dental flossing did not appear to decrease the risk of thrombotic stroke or lacunar stroke. The findings were independent of participants brushing habits or adherence to regular dental visits. In addition, the frequency of dental flossing had an inverse correlation with the risk of stroke.
The researchers hypothesized that since dental flossing is also linked to a reduced risk of dental caries and periodontitis, the practice could help mitigate inflammation. Study limitations included the questionnaire-based nature of the study, the focus on just stroke and cardiovascular outcomes, and the lack of follow-up concerning other oral health behaviors.
In a companion press release from the AHA, lead study author Souvik Sen, MD, MPH, of the University of South Carolina, said: “This study offers more insights into the specific dental health behaviors that may be linked to stroke risks and potential risk reduction. With further research, dental health practices could possibly be incorporated into the Life’s Essential 8 risk factors.”
