Flossing your teeth at least once a week may be linked to a lower risk of stroke caused by a blood clot blocking brain blood flow and irregular heartbeats, according to a preliminary study presented at the American Stroke Association’s International Stroke Conference 2025. Study lead author and chair of the Department of Neurology, Prisma Health Richland Hospital, Souvik Sen, said: “A recent global health report revealed that oral diseases – such as untreated tooth decay and gum disease – affected 3.5 billion people in 2022, making them the most widespread health conditions. We aimed to determine which oral hygiene behaviour – dental flossing, brushing or regular dentist visits – has the greatest impact on stroke prevention”.

The Atherosclerosis Risk in Communities (ARIC) study, one of the first large-scale investigations of this kind in the U.S., assessed the home use of dental floss through a structured questionnaire of more than 6,000 people. Among those who reported flossing, 4,092 had not experienced a stroke, and 4,050 had not been diagnosed with an irregular heartbeat known as atrial fibrillation (AFib). The analysis found:

• flossing was associated with a 22% lower risk of ischemic stroke, 44% lower risk of cardioembolic stroke (blood clots traveling from the heart), and 12% lower risk of AFib;
• the associated lower risk was independent of regular brushing and routine dental visits or other oral hygiene behaviours;
• increasing the frequency of flossing had a greater chance of stroke risk reduction; and,
• flossing was also associated with a lower chance of cavities and periodontal disease.

From: https://www.sciencedaily.com/releases/2025/01/250130161704.htm