How to brush your teeth can help prevent Alzheimer's disease?

For most people, cleaning your teeth can be part of your daily routine. But what if the way you clean your teeth today could affect your chances of getting Alzheimer's in the years to come?

There is growing evidence that gum disease (periodontitis) may be a plausible risk factor for Alzheimer's disease. Some studies even suggest that your risk doubles when gum disease persists for 10 years or more. Indeed, a new US study published in Progress of science details how a type of bacteria Porphyromonas gingivalis – or P. gingivalis – badociated with gum disease has been found in the brains of patients with Alzheimer's disease. Tests on mice also showed how the virus spread from the mouth to the brain, where it destroyed nerve cells.

The report in question was produced and self-financed by the founders of the American pharmaceutical company Cortexyme, which studies the cause of Alzheimer's disease and other degenerative disorders. Scientists at the San Francisco pharmaceutical company will launch a human trial later this year.

What is gum disease?

The first phase of gum disease is called gingivitis. This occurs when the gums become inflamed in response to the build-up of bacterial plaque on the surface of the teeth.

Gingivitis affects up to half of adults, but is usually reversible. If gingivitis is not treated, "subgingival pockets" are formed between the tooth and the gum, which are filled with bacteria. These pockets indicate that gingivitis is converted into periodontitis. At this point, it becomes almost impossible to eliminate bacteria, although a dental treatment can help control their growth.

The risk of gum disease increases considerably in unhygienic people. Factors such as smoking, drugs, genetics, food choices, puberty and pregnancy can all contribute to the development of the disease.

Although it's important to remember that gum disease is not just the job of P. gingivalis only. A group of organizations including Treponema denticola, Tannerella forsythia and other bacteria also play a role in this complex oral disease.

Brain-to-brain connection

At Central Lancashire University, we were the first to connect with P. gingivalis and completely diagnosed Alzheimer's disease. Subsequent studies have also revealed that this bacterium – responsible for many forms of gum disease – can migrate from the mouth to the brain in mice. And at the entrance of the brain, P. gingivalis can reproduce all the features of Alzheimer's disease.

Recent American research that has uncovered the bacterium of chronic gum disease in the brains of Alzheimer's patients provides other very solid evidence based on research – but it must be interpreted in context. And the fact is that Alzheimer's disease is linked to a number of other conditions and not just to gum disease.

Existing research shows that other types of bacteria and the herpes virus type 1 are also present in the brain of Alzheimer's disease. People with Down syndrome also have a higher risk of developing Alzheimer's disease, as do people who have suffered a serious head injury. Research also shows that many conditions badociated with cardiovascular disease may increase the risk of Alzheimer's disease. This suggests that there are many causes with only one endpoint – and scientists are still trying to determine the link.

This criterion causes the same symptoms of Alzheimer's disease: memory and behavioral disorders. This also occurs in parallel with the accumulation of plaques in the gray matter of the brain and so-called "neurofibrillary tangles". These are the debris left by the collapse of the internal skeleton of a neuron. These occur when a protein can no longer fulfill its function of stabilizing the cell structure.

Brush your teeth

The latest research adds more evidence to the theory that gum disease can lead to Alzheimer's disease. But before starting to panic while brushing your teeth, it's important to keep in mind that not all people with gum disease develop Alzheimer's disease and that all people with Alzheimer's disease Alzheimer's do not have gum disease.

To determine who is "at risk", scientists now need to develop tests that allow the dentist to know who to target. Dental clinicians can then advise these people on how to reduce the risk of developing Alzheimer's disease through better management of their oral health. But until then, it is recommended to brush regularly and maintain good oral hygiene.

Sim K Singhrao is a senior researcher in the faculty of dentistry., Central Lancashire University. This article originally appeared in The conversation