brushing teeth

A child brushing teeth with an older family member (Photo by Mikhail Nilov from Pexels)

KUOPIO, Finland — An international study finds that people with poor dental hygiene are 21 percent more likely to develop Alzheimer’s disease later in life.

Those with bad teeth or failing oral health are also 23 percent more likely to develop cognitive decline, which often leads to the devastating, memory-robbing condition. Scientists pooled data from 47 studies around the world. The results underline the importance of regular brushing and flossing, particularly during middle age.

Lead author Dr. Sam Asher from the University of Eastern Finland adds that tooth loss independently increases the risk of both cognitive decline (23%) and dementia (13%). The findings have clinical implications, as regular visits to the dentist may help prevent dementia, according to the researchers.

Globally, the number of dementia cases will triple to more than 150 million by 2050, estimates show. With no cure in sight, there is an increasing focus on lifestyle changes that keep the mind sharp.

“Periodontitis is the inflammation of tooth-supporting tissues which in severe cases leads to tooth loss. It affects about 10%–15% of the world’s adult population,” study authors write in the Journal of the American Geriatrics Society.

Gum disease can lead to problems throughout the body

Previous studies have linked gum disease to diabetes and cardiovascular illnesses. It can even lead to chronic systemic inflammation, Dr. Asher says.

Tooth loss may lead to people eating a less nutritious diet. Moreover, chewing boosts blood and oxygen flow to the brain. The analysis is among the biggest of its kind. It involved more than one million participants, many followed for over a decade.

“The findings of this review might indicate the involvement of multiple mechanisms in the association between periodontal and cognitive health,” researchers write.

Gum disease is believed to kill neurons by increasing the number of inflammatory chemicals in the blood.

Systemic inflammation per se is an independent determinant of cognitive deterioration and links other risk factors including diabetes, high blood pressure and cholesterol and even ageing to cognitive deterioration.”

Tooth loss may also impair brainpower by reducing jaw strength, leading to loss of grey matter. Dr. Asher says dentists are well placed to track and intervene in early changes in gum health and oral self-care. However, services need to remain consistent over time, while patients also maintain their own dental health at home when dentists discover a problem.

“From a clinical perspective, our findings emphasize the importance of monitoring and management of periodontal health in the context of dementia prevention, although available evidence is not yet sufficient to point out clear ways for early identification of at-risk individuals, and the most efficient measures to prevent cognitive deterioration,” the authors conclude in a media release.

South West News Service writer Mark Waghorn contributed to this report.

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  1. DF43566 says:

    Another spurious correlation, not likely replicated.

  2. John Barnett says:

    Such BS. Writing articles like this is simply called job security, and lying.

  3. Joe Bob says:

    Common sense, and also pretty much a given for some time now. The question of causality should be brought up, however, to play devil’s advocate in this matter. More clearly, a series of double blind, long term experiments would need to be conducted. Moreover, all other factors [age, income, location, gender, education, etc.] would need to be identified and eliminated as potential influencers.

    To put a finer point on it, could it not be argued that neglecting one’s oral hygiene could be a potential indicator of long-term dementia?

  4. Mj says:

    As has been stated in other comments. The content of these studies indicate that the are correlation in nature. While correlations studies provide information about an association between variables, they do not prove causality. The result of both variables could be the result of another unidentified variable such as general self-neglect or poor dietary habits. In addition each variable could a different causal variable . For example, watching TV incessantly and snacking in sugar laden foods and drinks.