Oral Health and Cognitive Decline: New CDC Research (2025)

A growing body of research suggests that the health of your mouth may be connected to the health of your brain. In 2025, the CDC published a study in its journal Preventing Chronic Disease (PCD) that found a significant link between poor oral health and subjective cognitive decline among adults aged 45 and older. This research adds to an expanding collection of evidence that oral health problems, particularly gum disease and tooth loss, may be associated with an increased risk of cognitive difficulties.

For the millions of older Americans already dealing with declining dental health, this research raises important questions. Periodontal disease affects roughly two in five adults between 45 and 64 years old, and about 17 percent of adults aged 65 and older have lost all of their teeth. Understanding the potential connection between oral health and cognitive function could change how we think about dental care as we age.

What the 2025 CDC Study Found

The 2025 CDC study analyzed data from the Behavioral Risk Factor Surveillance System (BRFSS), a large national health survey. Researchers examined the relationship between self-reported oral health indicators, such as tooth loss, gum disease, and overall oral health status, and self-reported subjective cognitive decline, which includes increasing confusion and worsening memory.

The findings showed that adults who reported poor oral health were significantly more likely to also report subjective cognitive decline. The association held even after researchers accounted for factors like age, education, income, smoking status, and chronic conditions such as diabetes and heart disease. This suggests that the link between oral health and cognitive decline is not simply explained by shared risk factors, though those factors certainly play a role.

Tooth loss showed a particularly strong association with cognitive decline. Adults who had lost a significant number of teeth were more likely to report worsening memory and confusion. Complete tooth loss, known as edentulism, was associated with the highest levels of subjective cognitive decline.

Potential Biological Mechanisms

While the CDC study establishes an association rather than a direct causal link, researchers have identified several biological pathways that could explain how oral health problems might contribute to cognitive decline.

• Chronic inflammation: Periodontal disease produces chronic systemic inflammation. Inflammatory chemicals released by infected gums enter the bloodstream and can cross the blood-brain barrier, potentially damaging neurons and contributing to neurodegenerative processes.
• Bacterial invasion: Oral bacteria, particularly Porphyromonas gingivalis (a key bacterium in gum disease), have been detected in the brains of Alzheimer's patients. These bacteria may travel from the mouth to the brain through the bloodstream or along nerve pathways, where they could trigger an immune response that damages brain tissue.
• Nutritional impact: Tooth loss can affect a person's ability to chew and eat a varied, nutritious diet. Poor nutrition, including deficiencies in vitamins and minerals important for brain health, may contribute to cognitive decline over time.
• Reduced chewing stimulation: Some researchers have proposed that chewing provides sensory stimulation to the brain. Tooth loss reduces this stimulation, which could theoretically contribute to cognitive decline, though this theory is still being explored.

What Earlier Research Has Shown

The 2025 CDC study is not the first to find a connection between oral health and cognitive function. Multiple studies over the past decade have contributed to this growing area of research. A 2020 study published in the Journal of the American Geriatrics Society found that older adults with more teeth had better cognitive function over time. A 2019 meta-analysis found that periodontitis was associated with a significantly higher risk of developing Alzheimer's disease.

The NIH's National Institute on Aging has also noted the association and has funded research to better understand the mechanisms involved. While individual studies vary in their methods and conclusions, the overall pattern across research is consistent: people with poor oral health tend to have higher rates of cognitive decline.

It is important to note that most of this research is observational, meaning it identifies patterns but does not prove that one condition causes the other. Clinical trials designed to test whether treating gum disease can prevent or slow cognitive decline are still in early stages.

Implications for Seniors

For older adults, the potential link between oral health and cognitive decline adds urgency to maintaining good dental care. Seniors already face heightened risks for both conditions. Periodontal disease becomes more prevalent with age, and cognitive decline, including dementia, primarily affects older populations. When you consider that many seniors lose their dental insurance upon retiring and that Original Medicare does not cover routine dental care, the situation becomes particularly concerning.

Seniors who lose dental coverage at retirement face an increased risk of neglecting their oral health. As dental problems accumulate without treatment, the potential downstream effects on cognitive health become a real concern. The dental care crisis facing seniors is not just about teeth. It may have implications for brain health as well.

Adults who are beginning to notice memory changes should not overlook their dental health. While there is no guarantee that treating gum disease will prevent cognitive decline, maintaining good oral health removes one potential contributing factor and supports overall well-being.

Maintaining Dental Health as You Age

Good oral health habits become even more important as you get older. Age-related changes like dry mouth, receding gums, and medication side effects can make dental problems more likely. Taking proactive steps can help protect both your teeth and potentially your cognitive function.

• Brush and floss daily: Brush twice a day with fluoride toothpaste and floss at least once daily. If arthritis or other conditions make brushing difficult, consider an electric toothbrush with a larger grip.
• See your dentist regularly: Regular checkups and professional cleanings help catch and treat gum disease before it becomes severe. If you have active periodontal disease, your dentist may recommend visits every three to four months.
• Address dry mouth: Many medications taken by older adults cause dry mouth, which increases the risk of cavities and gum disease. Stay hydrated and ask your doctor or dentist about managing dry mouth.
• Replace missing teeth: If you have lost teeth, talk to your dentist about replacement options. Dentures, bridges, or implants can restore your ability to chew properly and maintain good nutrition, which supports both physical and cognitive health.

Coverage Options for Preventive Dental Care

Since Original Medicare does not cover routine dental care, seniors need to explore other options. Several pathways can help you access the dental care that supports both oral and potentially cognitive health.

• Medicare Advantage plans: Many Medicare Advantage plans include dental benefits, sometimes at no additional premium. Coverage varies by plan and location, so compare options carefully during enrollment periods.
• Standalone dental insurance: Individual dental plans are available year-round and typically cover preventive care like cleanings and exams. Monthly premiums generally range from $20 to $60.
• Community resources: Federally qualified health centers (FQHCs), dental schools, and some nonprofit organizations offer dental services on a sliding fee scale based on income.

Looking Ahead: What This Research Means

The 2025 CDC study is part of a broader shift in how health professionals view the relationship between oral health and overall health. For decades, dental care has been treated as separate from medical care, both in clinical practice and in insurance coverage. Research linking oral health to conditions like cognitive decline, heart disease, and diabetes is challenging that separation.

Public health experts have increasingly called for integrating dental care into overall health care, especially for older adults. The evidence connecting oral health to cardiovascular disease, diabetes, and now cognitive decline strengthens the case that dental health is not a luxury but a medical necessity. For seniors, maintaining access to dental care is an important part of healthy aging.

While we wait for more definitive research, the practical advice is clear: take care of your teeth and gums. The potential benefits extend well beyond your mouth. Regular dental care, good oral hygiene, and addressing problems early are low-risk, high-reward strategies for supporting your overall health as you age.