The Chemistry of Fluoridated Water


Yes, there are chemicals in your drinking water. But there are also chemicals in your deodorant; and your organic, locally grown kale salad; and your dog. The word “chemicals” doesn’t mean that something is artificial or toxic; it just means “a substance produced by a chemical process.” The fluoride in your drinking water is a chemical, too. But what’s it doing in there?

Well, if it’s doing its job, that fluoride is reducing your risk of cavities. As you’ll see in the video above, from Reactions, fluoride can react with your tooth enamel at a molecular level, strengthening the barrier so that holes—cavities—can’t form.

Fluoride’s tooth-empowering abilities were first discovered in the early 1900s, by doctors who noticed lower rates of tooth decay in areas with naturally fluoridated water.

They collected evidence and conducted tests for decades, and in 1945, Grand Rapids, Michigan, became the first city to add fluoride to its public water supply. Other cities soon followed, and today, more than 200 million Americans drink fluoridated tap water. 

Like any public health project, fluoridated water is not without its detractors. Fluoridation conspiracy theories abound. Still, scientific studies have shown that, in reasonable doses, fluoride presents no health risks to the human body. It’s true that the teeth of people who consume too much fluoride may turn yellow or pitted, and that in high enough quantities, fluoride can be lethal, but so can, you know, apples and oxygen. Public health departments know of these risks and are careful to keep fluoride levels within a safe range. 

While fluoridated water is definitely safe, its efficacy is still up for debate. A 2015 literature review of 20 studies by an independent panel of doctors and researchers found that we just don’t have enough research to prove that fluoridated water improves public health, especially among adults. (The protection it provided against tooth decay for children was more evident.) But keep in mind that most of these studies were conducted before 1975, and three-fourths looked at areas with naturally occurring fluoridated water, not where fluoride had been added to the water supply. 

The bottom line: It might help, and it won’t hurt. And if you want to make sure your teeth stay healthy and strong, you can’t go wrong with boring old brushing and flossing.

Header image from YouTube // Reactions

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