Defending Fluoride in Water in a Changing Environment

Most of the U.S. population (72.3% as of 2022) has fluoride in its public drinking water supply.

Since 1945, when Grand Rapids, Michigan, became the first U.S. city to add carefully controlled amounts of the mineral to its water, so many Americans have benefitted from this public health intervention, long hailed as one of the nation’s most successful.

Recently, however, fluoride in water has become the subject of increased controversy.

U.S. Health Secretary Robert F. Kennedy Jr. has announced his intent to tell the Centers for Disease Control (CDC) to reverse its long-standing recommendation for fluoridated water. The Environmental Protection Agency (EPA) is reviewing “new scientific information on potential health risks of fluoride in drinking water.” And in 2025, Utah and Florida banned public water fluoridation.

Proponents of rolling back or ending water fluoridation say they are motivated by public health concerns. Most scientists, dental health professionals, and public health advocates, however, claim the criticism of fluoridation stems from misinformation, anti-scientific bias, and unproven conspiracy theories.

When patients here at Penn Dental Family Practice (PDFP) ask us, “Is fluoride bad for you?” we confidently say, “No!” In appropriate amounts, fluoride in water has been proven to strengthen tooth enamel, reduce cavities, and improve oral health.

Fluoride Is Nature’s Defense Against Tooth Decay

Fluoride is a naturally occurring mineral found in rocks, soil, and virtually all water sources, including oceans and rivers.

Fluoride protects our teeth by integrating into our enamel, creating a stronger, more acid-resistant surface. It also promotes remineralization, the natural restoration of weakened enamel before cavities can form.

Public Water Fluoridation Saves Both Teeth and Money

Community water fluoridation is the process of adjusting the natural fluoride levels in drinking water to the optimal concentration for preventing cavities. Drinking fluoridated water provides frequent, low-dose topical exposure by bathing the teeth in fluoride. Among the young, it also incorporates fluoride into developing teeth.

Based on careful review of scientific evidence, the CDC recommends 0.7 mg/L as “the concentration that maximizes fluoride’s oral health benefits while minimizing potential harms.” This concentration is roughly equal to three drops of water in a 55-gallon barrel.

Extensive research confirms that, on average, communities that drink fluoride in their water experience 25% fewer cavities among both children and adults. Fewer cavities mean not only less dental pain and fillings but also better oral health, since cavity-free mouths are less susceptible to infection, tooth loss, and gum disease.

Fluoridated water saves public health dollars, too. Every dollar invested in water fluoridation saves communities an estimated $38 in dental treatment costs. It is the most cost-effective method for delivering cavity prevention to a large population and helps everyone, no matter their age or income.

“Water fluoridation is a crucial preventive measure for community oral health,” writes Dr. Joan Gluch, former Division Chief of Community Oral Health at Penn Dental Medicine. “It plays a vital role in improving the overall health of communities by preventing dental caries [cavities], reducing health care costs, and addressing oral health disparities.”

Separating Fluoride Facts From Fiction

Some recent conversations about fluoride in water are clouded by a mix of myths and misconceptions that can overshadow the well-established benefits community water fluoridation provides.

Is Water Fluoridation an Unethical “Mass Medication?”

Unlike medications prescribed for individual use, water fluoridation is a community-wide public health measure aimed at preventing the common and costly disease of cavities (dental caries).

Like other, generally noncontroversial public health interventions such as iodizing salt or fortifying milk with vitamin D, fluoridation is based on solid scientific evidence and involves no synthetic medicines. It is an ethical application of science for widespread welfare, with the added advantage of requiring minimal individual compliance or effort.

Does Fluoride Stain Teeth?

Fluoride itself does not stain teeth. But excessive exposure to it during the early years of tooth development can lead to a condition called dental fluorosis, which can cause changes in tooth enamel’s appearance ranging from mild white spots to more severe brown stains and surface irregularities.

Dental fluorosis typically occurs in children up to roughly 8 years old who consume too much fluoride because they are swallowing toothpaste or taking supplements while also drinking fluoridated water. It is easily prevented by monitoring the amount of toothpaste children use and ensuring they spit it out.

Purely a cosmetic issue, dental fluorosis is not painful and does not affect the teeth’s function.

Does Fluoride Damage Bones and the Skeleton?

People exposed to extremely high levels of fluoride over many years, far exceeding the levels found in optimally fluoridated water, may develop a painful bone condition known as skeletal fluorosis.

Skeletal fluorosis is rare in the U.S., where the EPA currently sets an enforceable fluoride drinking water standard of 4.0 mg/L, far higher than the optimal 0.7 mg/L concentration. The condition is most common in parts of India, China, and Africa where natural groundwater contains excessive concentrations of fluoride.

In addition, studies show no increased risk of bone fractures from drinking water with optimal fluoride levels.

Does Fluoride in Water Lower IQ?

Headlines about a link between fluoride and low IQ stem from an evaluation of studies that showed an association between lower children’s IQ scores and estimated total exposure to fluoride from all sources, not from drinking water alone.

However, an association does not prove causation, and the fluoride levels in question were higher than both the World Health Organization’s (WHO) safe limit of 1.5 mg/L and the CDC’s 0.7 mg/L concentration.

“Although these studies are important to identify safety concerns with excessive amounts of fluoride,” Dr. Gluch writes, “they do not apply to the conditions of US water fluoridation.”

Additionally, none of the studies evaluated came from the U.S., but from other countries, in some of which fluoride levels were “more than 5 times the level used for water fluoridation” here.

Let PDFP Help You Proactively Care for Your Teeth

Philadelphia has been fluoridating its drinking water since 1951. Not all of its suburbs do. But whether or not you have access to fluoride in your public water supply, PDFP can help you take action to achieve and maintain your best oral health.

Our expert dental professionals can help you make sure you’re doing all you can to keep your teeth and mouth clean and healthy.

Schedule your appointment online or call us at 215-898-PDFP (7337).