ASA Research: Flossing Lowers Stroke and AFib Risk—Here’s How

A recent study, to be presented at the American Stroke Association’s International Stroke Conference 2025, reveals that regular dental flossing—at least once a week—may lower the risk of certain types of strokes and reduce the incidence of atrial fibrillation (AFib). The findings, emerging from the Atherosclerosis Risk in Communities (ARIC) study, provide compelling evidence that oral hygiene behaviors extend beyond dental health and have significant cardiovascular implications.

Key Findings and Data

• Risk Reduction:

• Ischemic Stroke: Flossing was associated with a 22% lower risk.

• Cardioembolic Stroke: A striking 44% reduction in risk was observed for strokes caused by blood clots traveling from the heart.

• Atrial Fibrillation (AFib): Regular flossers experienced a 12% reduction in the risk of developing AFib, the most common type of irregular heartbeat.

• Study Cohort Details:

• Participants: Over 6,000 individuals were surveyed.

• Stroke Outcomes: During a 25-year follow-up, 434 participants suffered strokes. The breakdown included 147 cases of large artery brain clots, 97 cardioembolic strokes, and 95 cases due to hardening of smaller arteries.

• AFib Incidence: A total of 1,291 participants were diagnosed with atrial fibrillation during the study period.

• Independence from Other Oral Hygiene Behaviors:

The risk reductions associated with flossing were found to be independent of other oral health practices such as regular tooth brushing and routine dental visits. This highlights flossing as a standalone protective measure against both oral and cardiovascular diseases.

Study Methodology and Participant Profile

• Data Collection:

The study utilized structured questionnaires to assess the home use of dental floss among participants.

• Participant Characteristics:

Average age was 62 years.

The cohort was predominantly white (82%), with 18% Black adults, and 55% of the participants were women.

• Exclusion Criteria:

Individuals with total tooth loss, dental implants, existing heart disease, organ transplants, artificial joints, implanted heart valves or stents, or those who had undergone major surgery were excluded to minimize confounding factors.

Potential Mechanisms

According to study lead author Souvik Sen, M.D., M.S., M.P.H., chair of the Department of Neurology at Prisma Health Richland Hospital, the benefits of flossing may stem from a reduction in oral infections and inflammation. Chronic oral infections are known to contribute to systemic inflammation and arterial hardening, which in turn elevate the risk for both strokes and irregular heart rhythms. This connection underscores the importance of maintaining optimal oral health as part of a broader strategy to prevent cardiovascular events.

Implications for Dental Practice

For dental professionals, these findings reinforce the importance of promoting flossing as an integral part of daily oral hygiene routines. The research offers several actionable insights:

• Patient Education: Emphasize to patients that flossing is not only crucial for preventing cavities and periodontal disease but may also play a role in reducing the risk of serious cardiovascular events.

• Preventive Strategies: Incorporate discussions about the cardiovascular benefits of flossing during dental consultations. Given the affordability and accessibility of dental floss, this preventive measure can be an easy addition to patients’ health routines.

• Interdisciplinary Collaboration: Encourage communication between dental and medical professionals to further explore the links between oral health and systemic conditions, potentially integrating flossing recommendations into broader cardiovascular health guidelines.

Study Limitations and Future Directions

While the findings are promising, several limitations must be acknowledged:

• Data Collection Method:

The reliance on self-reported questionnaire data may introduce recall bias.

• Follow-Up on Oral Hygiene Practices:

The study did not track changes in flossing behavior over the 25-year period.

• Preliminary Nature:

As an abstract presented at a scientific conference, these results are considered preliminary until validated by full, peer-reviewed publications.

Conclusion

This study adds to a growing body of evidence linking oral health to overall systemic health. For dental professionals, the clear message is that regular flossing can have far-reaching benefits, potentially reducing the risk of stroke and atrial fibrillation. In an era where interdisciplinary approaches to health are becoming increasingly important, these findings provide a robust basis for integrating dental care into preventive cardiovascular strategies.

Dental practitioners are encouraged to review the full research abstract and stay tuned for further developments as additional data emerges. The integration of oral health practices into overall health management continues to be a promising field for improving patient outcomes.

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