Fluoride is a mineral that naturally exists in all bodies of water — lakes, rivers, groundwater, and even oceans. In some areas of Idaho, the natural level of fluoride in water is enough to reduce the risk of tooth decay (cavities). Other areas need to add a little more fluoride or take some out to reach the scientifically-determined best (optimal) amount of 0.7 mg/L (milligrams of fluoride per liter). The process of adding fluoride to public water systems is called community water fluoridation. When drinking water contains the optimal level of fluoride, it helps to prevent cavities in teeth, lowers the need for dental work for children and adults, and helps create health equity. 

Water with the right amount of fluoride strengthens the outer layer of teeth called enamel. Fluoride makes the enamel more resistant to damage that can lead to a cavity. Fluoride works best when small amounts are present inside the mouth throughout the day. Besides drinking water, adults, children, and pregnant women can enjoy the benefits of fluoride from consuming other foods and beverages made with fluoridated water and by using toothpaste with fluoride.

Tap water is widely accessible and inexpensive. Optimally fluoridated drinking water is a good way to provide a layer of prevention to everyone, regardless of their age or income level. A report by the National Institutes of Health praises the impact of fluoridation because it “not only benefits the entire population but disproportionally benefits economically vulnerable groups” within a community. Community water fluoridation in America has been around for 79 years!

Both fluoridated water and fluoride toothpaste are proven to reduce the rate of tooth decay. But neither one is a replacement for the other. The CDC concludes that fluoride in the water and toothpaste “provide important and complimentary benefits.”

  • The U.S. Task force on Community Prevention Services examined 21 studies and concluded in its 2000 report that fluoridated water reduces tooth decay by a median rate of 29% among children ages 4 to 17.
  • Studies have shown that towns with fluoridated water have tooth decay rates that are 45% lower than towns without community water fluoridation.
  • The American Journal of Public Health found that the fluoridated water consumed as a young child makes the loss of teeth (due to decay) less likely once that child becomes a middle-aged adult.
  • Having fluoridated community water saves money because stronger teeth mean fewer treatment costs. In 2003, the state of Colorado estimates that it saved nearly $149 million by avoiding unnecessary treatment costs.
  • Health experts and scientists report that fluoridation reduces cavities by 25%. Keeping our teeth healthy means we can eat, speak, and smile with confidence.

Common Questions about Fluoride

Answered by the American Academy of Pediatrics/Campaign for Dental Health

Is Fluoride Safe?

Yes! Decades of research, experience, and the support of the world’s leading health, dental, and medical organizations have confirmed the safety of fluoride.
Are there health risks associated with fluoride?

No. There is no credible scientific evidence that fluoriated water or dental products can cause illness or disease.
Are the fluoride additives used to fluoridate drinking water safe?

Yes! The fluoride added to public water meets strict safety standards and complies with the Safe Drinking Water Act. But remember, in Idaho, no public water systems (except Mountain Home Air Force Base) add fluoride to reach optimal levels.
Is bottled water fluoridated?

Most bottled water is not fluoridated. If it is, it will say so on the label.
What is fluoriosis and how to prevent it?

Dental fluorosis is a slight change in the look of the teeth, usually in the form of very faint white markings. It is caused by consuming too much fluoride before the age of 8, while permanent teeth are still forming. To prevent fluorosis, follow dentist guidelines on how much toothpaste to use for children of different ages, make sure children spit toothpaste out after brushing, and do not use fluoride mouth rinses for children under six unless advised to do so by a dentist or other health professional.
Do refrigerator filters or water pitcher filters take out fluoride?

No. Only specialized reverse osmosis filter systems can remove fluoride.

What about the water in your house?

Finding the answer depends on where your family gets your drinking water. To explore the fluoride level in your community water system, visit My Water’s Fluoride, a national website managed by the CDC (Centers for Disease Control and Prevention).

  • Public water: If a community water system serves your home, ask to see your system’s water quality report to find out. This report should be available online from the entity that manages your water system or visit My Water’s Fluoride.
  • Private well water: Private wells are not regulated, so if you get your drinking water from a private source, it is important to test your water so you know how much fluoride is present. Water testing can also tell you whether arsenic, lead, or other contaminants may be present.
    Resource: What to know about Idaho Well Water

What can you do if your household water doesn’t have enough fluoride?

Once you determine the naturally occurring fluoride level for your public or private water system, you can take steps to change or supplement the amount of fluoride your family gets each day to help strengthen teeth and protect from cavities.

You can:

  • Work with your dental and medical providers to prescribe fluoride supplements
  • Work with your public water system manager to advocate for community water fluoridation
  • Drink tap water instead of bottled water
  • Use toothpaste with fluoride
  • Take advantage of school-based fluoride varnish programs for your children
  • Take your infant to the dentist either at the eruption of their first tooth, whichever comes first

These experts include the American Dental Association, American Academy of Pediatrics, American Public Health Association, and the Centers for Disease Control and Prevention.

Training for Water Operators

CDC Fluoridation Learning Online

Idaho Division of Public Health Well Water Testing Flow Chart Booklet