(Disclaimer: This transcript is auto-generated and may contain mistakes.)

There is no known use of fluoride in the body. They've never been able to demonstrate a sickness which has occurred because of lack of fluoride. They've never demonstrated biochemically that there's any process in the body that needs fluoride. The only place where it seems that fluoride has some kind of possible role is in hardening the enamel, but it's a topical effect. It doesn't work through the gums into the teeth and it works on the outside of the teeth. In fact, once the enamel is formed, it's essentially dead tissue. So we're talking about a chemical interaction with dead tissue, hardening it. Once the fluoride is exchanged with the hydroxide ion, it makes the enamel harder, more resistant to acid attack and the acids come from the breakdown of sugars by bacteria in the mouth. .