FDA updates fluoride supplement guidance for children. Here's what you should know.

In todays Health Alert, the FDA is updating guidance on fluoride supplements for children. This update comes after the agency released a new analysis that raised questions about their safety and effectiveness.

The FDA says fluoride supplements should no longer be used in children under three, and in older children who are at low or moderate risk for tooth decay. Previously, babies as young as six months could be prescribed them.

Fluoride is a naturally occurring mineral. It helps prevent cavities by strengthening tooth enamel. Thats the hard, outer layer that can wear down from acids produced by bacteria, plaque, and sugars in the mouth.

Now, many Americans live in areas where fluoride is added to public water systems. That started back in 1945. But in communities without fluoridated wa