Topical fluoride use not proven to cause dementia

March 15, 2023 GMT

CLAIM: Dental products containing fluoride are unsafe because the substance has been directly linked to dementia and Alzheimer’s.

AP’S ASSESSMENT: False. Experts say there is no research showing that topical products containing fluoride — such as toothpaste and mouthwash — cause dementia or Alzheimer’s. Fluoride is naturally present in water and also added to some public water supplies to promote oral health. But consuming high levels of fluoride isn’t without health risks, such as brittle bones, and some studies have suggested too much fluoride in young children may be related to IQ or neurodevelopmental issues.

THE FACTS: A video shared on Instagram is cautioning users against going to dentists while baselessly asserting that dental products containing fluoride are unsafe. In the video, a man calls dentists “one of the biggest scams I’ve ever seen.”

“A dentist who’s telling me to brush with toothpaste that has fluoride, they’re trying to get me to rinse my mouth with fluoride,” he claims, later adding: “They don’t know that fluoride is a neurotoxin that’s been directly linked to dementia and Alzheimer’s.”

But experts say there is no research proving that topical fluoride products — in other words, products not intended for digestion, such as toothpaste and mouthwash — cause dementia or Alzheimer’s.

Christine Till, a neuropsychologist and professor at York University in Canada who has researched fluoride, said she was not aware of studies linking topical fluoride use to those conditions.

And the Centers for Disease Control and Prevention’s Division of Oral Health told The Associated Press in a statement that the agency “is not aware of any study that purports to link use of topical fluoride products, when used appropriately, to any systemic health risk.”

“CDC carefully and continuously monitors emerging research about fluoride so that recommendations can maximize benefits and minimize any potential risks,” it added.

Fluoride is a naturally occuring mineral that’s found in water but also used in toothpaste and dental products to strengthen teeth; it can also be found in foods and beverages. For decades it has also been added to many public water supplies as an oral health measure, the CDC explains. But excessive levels of consumption can present health risks such as brittle bones.

The U.S. in 2015 lowered the recommended amount of fluoride in drinking water because some kids were getting too much, causing white splotches on their teeth.

Fluoride consumption has continued to stir controversy and scientists say there is evidence that consuming fluoride in high levels may pose further risks, particularly for young children.

“I’m quite convinced that in utero or infantile exposure to fluoride ingestion is not a good thing for the developing brain of children,” said Linda Birnbaum, a former director of the National Institute of Environmental Health Sciences, part of the National Institutes of Health, and of the National Toxicology Program.

The National Toxicology Program has been continuing to evaluate the issue. In a September 2022 working draft of a report posted Wednesday the program said there is “a large body of evidence on IQ effects in children” and more limited evidence suggesting “other neurodevelopmental and cognitive effects in children.” The strongest evidence available is associated with levels higher than the currently recommended levels in drinking water in the U.S. An NTP spokesperson emphasized the report is not final.

Jennifer Sass, a senior scientist at Natural Resources Defense Council, said the legitimate concerns in the scientific community about fluoride consumption don’t justify avoiding the dentist because of topical fluoride use.

“Having poor teeth is one of the biggest health problems in America,” she said. Poor oral health is associated with other chronic diseases.

The CDC advises that children less than age 2 only use toothpaste with fluoride if recommended by a dentist or doctor.


This is part of AP’s effort to address widely shared misinformation, including work with outside companies and organizations to add factual context to misleading content that is circulating online. Learn more about fact-checking at AP.