Alzheimer’s disease has long been a medical mystery, but what if researchers have been searching for its causes in the wrong places?
A theory proposed by a group of health experts in 2019 suggests that something inside the mouth could actually trigger the memory-deteriorating condition.
Alzheimer’s symptoms appear when parts of the brain shrink (a process called atrophy), which disrupts the structure and function of specific brain areas, according to the NHS. Traditionally, it’s believed that this shrinkage results from age-related brain changes, genetics, and various environmental and lifestyle factors.
But what if the mouth plays a more significant role in the early stages of Alzheimer’s?
A study published in 2019 revealed a link between a common mouth infection and a decline in brain function, specifically gum disease. Further research by University of Louisville microbiologist Jan Potempa found that the pathogen responsible for chronic gum disease, known as periodontitis, was present in the brains of deceased Alzheimer’s patients.
This isn’t the first time a connection between oral health and Alzheimer’s has been identified. Earlier experiments in mice showed that an oral infection with the bacteria Porphyromonas gingivalis led to brain colonization.
An increase in the production of amyloid beta, the proteins commonly linked to Alzheimer’s disease, was also discovered in the 2019 study.
While the researchers behind this study do not claim to have definitively identified the cause of Alzheimer’s, they emphasized the importance of considering oral health when discussing potential Alzheimer’s diagnoses with patients.
Stephen Dominy, co-founder of the pharmaceutical startup Cortexyme, which led the research, explained to the press, “Infectious agents have been suspected in the development and progression of Alzheimer’s before, but the evidence of causation has not been convincing.”
He continued, “Now, for the first time, we have strong evidence connecting the intracellular, Gram-negative pathogen P. gingivalis with the development of Alzheimer’s.”
The team also identified toxic enzymes known as gingipains, which are produced by the gum disease bacteria, present in the brains of Alzheimer’s patients.
These toxic enzymes were also detected in the brains of several deceased individuals who had not been diagnosed with Alzheimer’s.
While this suggests a connection between gum disease and Alzheimer’s, it remains unclear whether gum disease contributes to the development of Alzheimer’s or if dementia itself leads to a decline in oral health.
