As a natural cavity fighter, fluoride is important in maintaining oral health. Fluoride is even added to some countries’ public water supplies, including the United States, to help citizens maintain good oral health. What is fluoride? It is a naturally occurring mineral that is found in the environment. Teeth receive and lose minerals everyday through the enamel coating. Acid attacks the enamel when minerals are lost. Fluoride works to protect the enamel by making the surface of the teeth resistant to harm done by acidic foods and drinks.