At the American Association for the Advancement of Science (AAAS) annual meeting in Phoenix, Arizona, experts presented growing evidence linking oral bacteria and gum disease to systemic inflammation that can affect organs and tissues throughout the body.
“Advanced gum disease, or periodontitis, does not directly cause conditions such as dementia, but it may accelerate disease in people already at risk,” said Alpdogan Kantarci, a professor of dentistry at the University of Minnesota. “We are now seeing that people with mild or moderate conditions who maintain good oral care – brushing, regular dental visits, and professional cleanings – show significantly better cognitive outcomes.”
Professor Kantarci highlighted experimental studies in mice showing that periodontitis can trigger brain inflammation and that harmful oral bacteria can cross the blood-brain barrier, particularly in older animals.
Other researchers on the panel described additional links between oral health and systemic disease. Dr. Felipe Andrade, an associate professor of medicine at Johns Hopkins, presented evidence that the bacteria responsible for gum disease may contribute to rheumatoid arthritis. Dr. Nobuhiko Kamada from the University of Michigan explained how oral pathogens can alter the gut microbiome, potentially raising the risk of inflammatory bowel disease and colorectal cancer.
“Oral health appears to influence more than 50 conditions,” Professor Kantarci said, citing connections to heart disease, stroke, and diabetes, in addition to neurological, musculoskeletal, and digestive disorders.
Experts warned that modern diets rich in sugar and ultra-processed foods are driving a surge in tooth decay and gum disease. Professor Kantarci noted that in some developed countries, poor diet and soft processed foods have created oral health problems comparable to those in lower-income nations.
Official statistics support these concerns. The Oral Health Survey for England showed that while obvious tooth decay had fallen from 46% of adults in 1998 to 28% in 2009, rates have climbed again, with the 2023 survey reporting that 41% of adults with natural teeth show decay. Signs of periodontal disease were observed in 93% of participants, including inflammation, tartar build-up, and gum “pocketing.”
Professor Kantarci stressed that food delivery services and processed diets are contributing to this decline. “This shift away from natural eating and home cooking is affecting oral health, which in turn is linked to higher rates of systemic disease,” he said.
The AAAS panel called for global collaboration to better understand how oral bacteria interact with other body systems. Professor Kantarci also emphasized practical steps for individuals: brushing two to three times daily, especially after consuming sticky or sugary foods, and using electric toothbrushes to improve cleaning efficiency for older adults or those with limited dexterity.
“This isn’t just about preventing cavities,” he said. “Good dental habits may be one of the most accessible ways to reduce the risk of some of the most feared diseases of aging.”