Many U.S. cities adjust the fluoride in their public water to help prevent tooth decay. Fluoridation has also become a subject of public debate and policy change in recent years. This guide explains what community water fluoridation is, what the American Dental Association (ADA) says about it, and how to find out what’s in your own water.
What community water fluoridation means
Fluoride is naturally present in water sources such as rivers, lakes, groundwater and oceans. The ADA describes fluoridation as adjusting that naturally occurring fluoride to an optimal level for preventing tooth decay. It compares this to fortifying milk with vitamin D, salt with iodine and bread with folic acid.
How much fluoride
The ADA says the recommended level for community water systems is 0.7 milligrams per liter. To put that in perspective, the ADA compares it to one inch in 23 miles, or one cent in $14,000.
How many people have it
According to the ADA, citing the latest CDC data, 72.3% of the U.S. population on public water systems (209 million people) had access to optimally fluoridated water in 2022.
What the ADA says about benefits
- Fewer cavities. The ADA says studies show fluoride in community water prevents at least 25 percent of tooth decay in children and adults, even with fluoride toothpaste widely available.
- Stronger enamel. Fluoride protects against decay by making tooth enamel stronger.
- Cost. The ADA says the average lifetime cost per person to fluoridate a water supply is less than the cost of one dental filling. For most municipalities, it says every $1 invested saves $38 in dental treatment costs.
- Endorsements. The ADA notes the CDC named fluoridation one of 10 great public health achievements of the 20th century. More than 100 health organizations, including the CDC, the American Medical Association, the World Health Organization and the American Academy of Pediatrics, have joined the ADA in recognizing its benefits.
Is it safe?
The ADA says fluoride at the recommended level is not toxic according to the best available scientific evidence. Toxicity depends on dose, and like salt, iron or vitamins, fluoride can be harmful only in massive amounts. The ADA “unreservedly endorses” fluoridation as safe, effective and necessary.
Fluorosis
Too much fluoride while children’s teeth are forming can cause dental fluorosis, usually faint white marks. The ADA says public water systems must notify customers if natural fluoride exceeds 2.0 mg/L. Families with young children above that level should consider other water sources.
The policy debate
Fluoridation policy is changing in some places. The ADA’s own fluoride page tracks news including a state fluoridation ban in Utah, a court order directing the EPA to address fluoride in drinking water, and FDA action on ingestible fluoride prescription products. Rules where you live may change, so check current local information rather than assuming.
How to check your water
- Public water: the ADA points to the CDC’s “My Water’s Fluoride” tool to see if your system is fluoridated. Your water utility’s annual water quality report is another place to look.
- Private well: the ADA notes the EPA recommends testing private well water once a year, and suggests checking fluoride yearly, especially with young children,.
- Bottled or filtered water: ask your dentist whether your family needs other fluoride sources.
Other ways to get fluoride
Fluoride toothpaste, and professional fluoride treatments at the dentist, also help prevent decay. See our fluoride treatments guide, how to choose a toothpaste and tooth decay guide. The ADA suggests asking your dentist, pediatrician or physician about your family’s fluoride needs.
Frequently asked questions
What level of fluoride is recommended?
The ADA says 0.7 milligrams per liter for community water systems.
Do I still need fluoride toothpaste if my water is fluoridated?
The ADA says water fluoridation prevents at least 25 percent of decay even with widespread fluoride toothpaste use. The two work together. Ask your dentist what’s right for you.
How do I know if my water has fluoride?
Check the CDC’s My Water’s Fluoride tool or your utility’s water quality report. Test private wells yearly.
Sources
- ADA MouthHealthy: Fluoride in Water
- American Dental Association: Fluoride in Water
- ADA MouthHealthy: Fluorosis
By the Dentist Review Editorial Team.
This article is for general information only and is not medical advice. Talk to a licensed dentist about your own situation. See our disclaimer.
Featured image: “Person fills glass with water at kitchen sink closeup” by Shixart1985, via Wikimedia Commons, licensed CC BY 2.0. Resized and compressed for the web.
Our guides are written and reviewed by the Dentist Review editorial team. We research each topic using public, authoritative sources such as the CDC, the National Institutes of Health (NIH/NIDCR), the American Dental Association (ADA) and CMS, and we update guides when guidance changes. Guides are for general information only and are not dental or medical advice; please read our disclaimer and learn more about us.