Fluoride plays a key role in preventing and controlling tooth decay from infancy through old age. In fact, community water fluoridation has been identified by the Centers for Disease Control as one of 10 great public health achievements of the 20th century. Still, too much of a good thing can have negative effects. It is important to be aware of how much fluoride young children are taking in.

Some young children can develop changes within the outer surface of the tooth called enamel fluorosis, if exposed to too much fluoride. Enamel fluorosis appears as faint white markings on the surface of the teeth but does not affect the function of the teeth. Enamel fluorosis can occur on baby and permanent teeth while they are forming under the gums. Once the teeth come into the mouth they are no longer able to develop this condition. Typically, very mild or mild fluorosis is barely noticeable.

Infants and young children are exposed to fluoride from a variety of sources such as commercially available baby food, fruit juices, toothpaste and fluoridated water. Most water districts in King County fluoridate water. Naturally occurring fluoride is frequently present in drinking water systems in Washington State. In Washington State the fluoride levels in public water systems are maintained at 0.8 to 1.3 mg/L which meets CDC guidelines.

It now appears that the amount of fluoride contained in the water, when used for mixing concentrated infant formula (either powdered or liquid), may influence a child’s risk for developing mild enamel fluorosis, particularly if this is the child’s sole source of nutrition. If tap water is fluoridated or has substantial natural fluoride (0.7mg/L or higher), parents may want to consider using a low-fluoride alternative water source.

The bottom line is that it is important to have fluoridated water. However infants less than one year old need less fluoride than everyone else because they are so small. If you have questions about the fluoride level in your water supply, contact your local public utility district.