Public water fluoridation — hailed by the Centers for Disease Control and Prevention as one of the top 10 public health achievements of the 20th century — is increasingly under scrutiny after Utah became the first state last week to ban its use. Now, other states are considering similar legislation.
The practice began after a 1945 study in Michigan demonstrated a 60% reduction in dental cavities among schoolchildren who consumed fluoridated water. Today, nearly three out of four Americans drink fluoridated public water. It has become the cornerstone for the prevention of tooth decay, one of the most common chronic diseases in children and adults.
Fluoride builds and strengthens tooth enamel against decay, serving as a protective barrier against cavities and an array of diseases that come from poor oral health. It is most effective when present in the saliva, continually bathing and protecting teeth. This is why water fluoridation is considered far more effective than fluoride toothpaste alone.
The U.S. Public Health Service recommends an optimal fluoride concentration in drinking water of 0.7 milligrams per liter (mg/L) of drinking water (lowered from 1.2 mg/L in 2015).
In New York, 71.7% of residents consume fluoridated water — a decision made at the municipal level. Many rural counties rely on residential wells as their source of drinking water, but the amount of naturally occurring fluoride from rocks and soil is too low to prevent tooth decay. For example, Poughkeepsie — which has unfluoridated water — reports a natural fluoride level of 0.06 mg/L,
Columbia County has no public water fluoridation; Ancram has no town water at all. An estimated 0.1% of Dutchess County municipalities add fluoride to their water (sections of Pleasant Valley). Pine Plains community water, used by 880 of the 2,200 residents, is unfluoridated. The towns of Stanford and Milan have no municipal water.
Low rates of fluoridation, the high cost of dental insurance, and a shortage of dentists are the primary reasons for the higher rates of untreated cavities and tooth loss in rural areas (up to a 51% incidence) vs urban (an average 38% incidence). Columbia County has been designated as a Health Professional Shortage Area for dental care.
Untreated tooth decay can cause gum disease, abscesses, and tooth loss, but is also linked to increased risk of systemic diseases, such as rheumatoid arthritis, Alzheimer disease — even head and neck cancer. A 30-year study published in the International Journal of Epidemiology in April 2022, found that adults with untreated decay and resulting lost permanent teeth had a significant increase in death from heart disease — the number one killer of American men and women.
Researchers have shown that public water fluoridation prevents at least 25% of tooth decay in children and adults through their lifespan. It is also cost-effective: Fewer cavities mean fewer dental treatments, saving an average of $32 per person annually — a total of $6.5 billion nationwide.
But recent studies have raised questions about the potential risks of drinking water with added fluoride. A review published by the National Toxicology Program in August 2024, concluded that higher levels of fluoride — more than double the amount in fluoridated public water — are linked to lower IQs in children. Excessive fluoridation has also been associated with skeletal fluorosis (brittle bones more susceptible to fracture), and thyroid dysfunction. No clear link has been found between water fluoridation and cancer.
Last September, U.S. District Judge Edward M. Chen rendered a verdict against the Environmental Protection Agency, responsible for setting the drinking water standards for fluoride. The court tasked the EPA to review and strengthen its fluoride regulations, citing “substantial and scientifically credible evidence establishing that fluoride poses a risk to human health” — without concluding that current public water fluoride levels are dangerous.
The EPA is appealing the decision to the U.S. Court of Appeals, supported by a coalition of 13 national medical and dental societies.
Last November, Secretary of Health and Human Services Robert F. Kennedy, Jr. promised that the current administration will “advise all U.S. water systems to remove fluoride from public water”, calling the additive “industrial waste”. Fluorosilicic acid, a by-product of fertilizer manufacturing, is the most common type of fluoride added to public water, and meets the safety standards of American Water Works Association.
Nebraska, South Carolina, Florida, Kentucky, Georgia, and Ohio have proposed legislation prohibiting fluoridation.
For those living in areas without fluoridated water, the CDC recommends brushing teeth twice a day with fluoride toothpaste, daily flossing, and if possible, dental checkups every six months — where in-office fluoride treatments may be considered.
Dr. Mary Jenkins, a contributor to the Herald and member of its board of directors, retired after nearly 40 years as a family practice physician in New York state.