Fluoride added to drinking water is safe and beneficial

Fearmongering about fluoride in the water is nothing new, dating to the 1950s, but now there’s a modern-day method for doing it: social media.

A viral Instagram post said two forms of fluoride in our drinking water "are so toxic that the CDC clearly labels these chemicals extremely toxic in both animals and humans." The post says, "It’s hard to see what’s going on when you’re still drinking fluoridated water."

The post was flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

Fluoride and other substances — including salt, iron, vitamin D and chlorine — are safe in small amounts but can be toxic in very large amounts, according to the Centers for Disease Control and Prevention. The amount of fluoride added to drinking water is not toxic.

How much is a toxic dose? At the recommended fluoride levels to prevent tooth decay, an adult male who weighs 155 pounds would have to drink about 1,900 eight-ounce glasses of water — nearly 120 gallons — in one sitting in order to reach a toxic level of consumption, according to the American Dental Association.

The CDC notes that "exposure to higher levels of fluoride may harm your health," and ingesting extremely large amounts can cause death.

Adding fluoride to the drinking water supply, sometimes called community water fluoridation, began in the U.S. in 1945 as a way of combating tooth decay, particularly in children. It’s considered to be a safe, cost-effective way to prevent cavities, and the CDC named community water fluoridation one of the 10 greatest public health achievements of the 20th century. 

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Fluoride is an element that occurs naturally in rivers, lakes, oceans, rocks and soil. Bodies of water in and around the U.S. have naturally occurring fluoride levels from 0.1 to 12 parts per million. The recommended level for preventing tooth decay is between 0.7 and 1.2 parts per million. 

The types of fluoride added to drinking water typically are extracted from phosphate rock, and after the extraction, the rock is used to create fertilizer. 

"Opponents use this message a lot, maybe because they want to create the false impression that fluoride comes from fertilizer," according to the Campaign for Dental Health, a program of the American Academy of Pediatrics. In fact, the Instagram post also makes the claim that the "two forms of fluoride that end up in our water...are by-products of the refining and fertilizer industries."

Another substance extracted from phosphate rock, phosphoric acid, is an ingredient in some Coca-Cola products.

An Instagram post said two forms of fluoride in our drinking water "are so toxic that the CDC clearly labels these chemicals extremely toxic in both animals and humans."

While fluoride can be toxic in massive amounts, the amount of fluoride added to drinking water is not toxic, and it would be impossible to drink enough of it to reach a toxic dose of fluoride.

We rate this claim about drinking water False.