Scientists warn that gum disease may damage the brain

White matter consists of bundles of nerve fibers that allow different parts of the brain to communicate. When this tissue is damaged, it can interfere with memory, thinking, balance, and coordination, and has also been linked to an increased risk of stroke.

White matter hyperplasia often increases with age and is considered a sign of underlying brain injury. Researchers believe that chronic inflammation in the mouth can affect the health of blood vessels in the brain, although more work is needed to confirm how the two are linked.

The oral health and brain health connection

“This study shows a link between gum disease and white matter hyperdensity, suggesting that oral health may play a role in brain health that we are only beginning to understand,” said study author Souvik Sen, MD, MS, MPH, of the University of South Carolina in Columbia. “While more research is needed to understand this relationship, these findings add to growing evidence that maintaining your oral health may support brain health.”

The researchers examined 1,143 adults with an average age of 77 years. Each participant underwent a dental examination to assess gum health. Of the total group, 800 had gum disease, while 343 did not. Participants also received brain scans to look for evidence of small vessel disease of the brain, a condition that involves damage to small blood vessels in the brain. This type of disease can appear on imaging as white matter hyperintensities, small cerebral hemorrhages, or lacunar infarcts, all of which become more common with age and are associated with stroke risk, memory problems, and movement difficulties.

Measuring brain changes

Those with gum disease were found to have a higher average volume of white matter hyperintensity, at 2.83% of total brain volume, compared to 2.52% in those without gum disease. The researchers grouped participants based on the magnitude of this hyperintensity. Individuals in the highest category had more than 21.36 cc of affected tissue, while individuals in the lowest group had less than 6.41 cc.

Among people with gum disease, 28% were in the highest group, compared to 19% of people without the condition. After adjusting for other factors including age, gender, race, blood pressure, diabetes and smoking, participants with gum disease had a 56% greater likelihood of being in the group with the greatest white matter damage.

The researchers found no link between gum disease and two other types of brain changes associated with small vessel disease: cerebral microbleeds and lacunar infarcts. This suggests that the observed association may be specific to white matter damage and not to all forms of small vessel injury.

Why can oral care be important for the brain?

“Gum disease is preventable and treatable,” the senator said. “If future studies confirm this link, it may provide a new way to reduce cerebral small vessel disease by targeting oral inflammation. For now, it underscores how dental care can support long-term brain health.”

One limitation of the study is that the dental evaluations and brain scans were performed only once, making it difficult to track how these conditions change over time. However, these findings add to a growing body of research suggesting that maintaining oral health could play a larger role in protecting the brain than previously recognized.