If you look at any tube of toothpaste with the American Dental Association’s Seal of Acceptance, you’ll see fluoride listed as the active ingredient.
Trace amounts of fluoride are also added to the drinking water in many communities to further promote strong and healthy teeth. But what is fluoride and how does it work?
First, let’s take a look back at the fascinating history of this mineral. It all starts in Colorado Springs at the turn of the 20th century. Dentists in the town encountered numerous cases of “Colorado brown stain” — tooth discoloration that, bizarrely, was connected to a lower rate of cavities. Today, we call that fluorosis. Eventually, they traced it back to the water supply and discovered naturally occurring fluoride to be the cause.
Dentists were curious to see whether it was possible to keep the cavity prevention without any of the staining by lowering the level of fluoride, and they were right! When fluoride was first added to the public water supply in Grand Rapids, Michigan, it reduced the rate of childhood dental caries by a whopping 60 percent, with no adverse effects except for occasional cases of mild fluorosis.
Today, more than half of the U.S. population lives in communities with fluoridated water, and the CDC considers community water fluoridation “1 of 10 great public health achievements of the 20th century,” benefiting young and old, rich and poor alike. It’s similar to drinking milk with vitamin D, baking with enriched flour, or even using iodized salt.
So how does fluoride actually protect teeth? It does it by helping to remineralize weakened tooth enamel and reverse the early signs of tooth decay. Brushing your teeth with fluoride toothpaste gives a topical benefit, while fluoride from foods and drinks serves as an ongoing benefit by becoming part of your saliva, where it can provide continual remineralization.
As was the case in Colorado Springs a hundred years ago, it’s definitely possible to have too much fluoride. This is why it’s important to spit after brushing with a fluoride toothpaste instead of swallowing and only use tiny amounts of toothpaste when brushing the teeth of babies and small children, if any. It’s also why fluoridated water supplies maintain the level at a very low 0.7-1.2 parts per million. Using more fluoride than the recommended amounts won’t increase the positive effects, but avoiding it entirely will make it harder to prevent cavities.
There’s a lot of information out there about fluoride, and not all of it is from credible sources like the ADA and CDC. If you have any questions, feel free to ask! We want to make sure our patients are confident and informed about the tools they have to keep their teeth healthy and strong!
Top image used under CC0 Public Domain license. Image cropped and modified from original.