A long-term study has found that adults with both gum disease and cavities face an 86% higher risk of stroke compared to those with healthy mouths. The research also linked poor oral health to a 36% increased likelihood of heart attacks and other cardiovascular problems.
The study, conducted by the University of South Carolina, tracked nearly 6,000 adults over 20 years. Researchers discovered that those who visited the dentist regularly were 81% less likely to have both gum disease and cavities.
“People with both cavities and gum disease had almost twice the risk of stroke compared to those with good oral health, even after accounting for cardiovascular risk factors,” said study author Dr. Souvik Sen. “Improving oral health may be an important part of stroke prevention.”
The study followed 5,986 participants with an average age of 63, none of whom had experienced a stroke at the start. Dental exams categorized participants into three groups: healthy mouth, gum disease only, or gum disease with cavities.
Ischaemic strokes, the most common type, occur when a blood clot or blockage limits oxygen and nutrients to the brain. Over two decades, participants were monitored through phone interviews and medical records for stroke occurrences.
Among those with healthy mouths, 4% suffered a stroke, compared with 7% of participants with gum disease alone and 10% of those with both conditions.
After adjusting for factors such as age, smoking, and body mass index, the data showed an 86% higher stroke risk for participants with both gum disease and cavities, while those with gum disease alone had a 44% higher risk.
Beyond stroke, participants with both conditions also had a 36% higher chance of major cardiovascular events, including heart attacks and fatal heart disease.
Regular dental visits had a clear protective effect. Participants who saw a dentist routinely were 81% less likely to have both gum disease and cavities, and 29% less likely to have gum disease alone.
“This study shows that caring for your teeth and gums isn’t just about a bright smile — it may also protect your brain,” Dr. Sen said. “Anyone with signs of gum disease or cavities should seek treatment to preserve oral health and potentially reduce stroke risk.”
The researchers noted that oral health was assessed only at the study’s start, so changes over time were not captured. They also acknowledged that other lifestyle or health factors could have influenced the results.
The findings indicate a strong link between oral and brain health, though they do not prove a direct cause-and-effect relationship.
