Your mouth and brain might seem unrelated, but recent studies show a clear connection between dental health and brain function. Keeping your teeth and gums healthy could help protect your memory and lower the risk of problems like Alzheimer’s disease.
Researchers found that losing teeth weakens a key part of the brain in mice. In one study, mice that had molars removed showed memory decline, even when they ate a normal diet. This happened because less chewing led to inflammation and cell loss in the hippocampus, the brain area for memory.[1] The team noted that tooth loss alone, not poor nutrition, caused these changes, and they hope dental treatments like prosthetics can prevent this in people.
Gum disease plays a big role too. Bacteria from infected gums, such as Porphyromonas gingivalis, can travel through the blood to the brain. There, they trigger inflammation, damage the blood-brain barrier, and produce harmful proteins linked to Alzheimer’s.[2][3][4][6] Scientists discovered these bacteria and their toxic enzymes, called gingipains, in the brains of Alzheimer’s patients and even in some healthy people who might have developed the disease later.[4] One review of studies showed people with poor oral health have more than twice the risk of Alzheimer’s.[2]
Flossing and brushing matter a lot. A look at 14 studies linked more missing teeth to higher chances of dementia. Each lost tooth raised the risk, possibly due to gum inflammation or eating softer, less nutritious foods without dentures.[3] Good habits like daily flossing may cut down on these bacteria and protect against cognitive decline.[3]
Other factors connect the two. Poor oral health ties to whole-body inflammation that affects the brain, similar to links with heart disease.[3][7] Oral microbiome imbalances, or dysbiosis, with bacteria like Treponema denticola, also fuel brain inflammation in Alzheimer’s.[6] New work from dental schools stresses that routines like interdental cleaning and checkups could reduce long-term brain risks.[2][5]
Maintaining strong teeth through chewing, cleaning, and care supports brain health as we age.
Sources
https://www.hiroshima-u.ac.jp/en/news/94785
https://armoneyandpolitics.com/lyon-college-oral-health-alzheimers/
https://www.babylondentalcare.com/blog/flossing-your-teeth-may-protect-against-cognitive-decline/
https://www.sciencealert.com/the-cause-of-alzheimers-may-be-coming-from-within-your-mouth
https://www.albertadentalassociation.ca/2025/12/12/new-research-links-oral-health-to-alzheimers-prevention/
https://pmc.ncbi.nlm.nih.gov/articles/PMC12701368/
https://www.dentalhealth.org/news/five-conditions-that-can-be-affected-by-poor-oral-health
