Why fluoride fears are mostly overblown

Decades of research and public health data consistently show that water fluoridation is an effective way to prevent tooth decay across populations, and communities with fluoridated water generally have lower rates of cavities compared to those without fluoridation.

According to the CDC, community water fluoridation safely and inexpensively reduced cavities in children by 40 to 70% and tooth loss in adults by 40 to 60 percent between 1945 and 1999.

Moreover, the cost of water fluoridation is minimal—typically less than $1 per person per year in the United States, and the return on that investment is substantial, with studies estimating that every $1 spent on water fluoridation saves about $20 to $50 in dental treatment costs. Fluoridation decreases the need for fillings, extractions, and other dental procedures, which are far more expensive than preventive measures.

That said, a lot has changed since community water fluoridation was first introduced.

With other improvements in oral health—including the availability of fluoridated toothpaste and school-based oral health programs—studies show that fluoride is no longer the silver bullet that it may have been when it was first introduced.

A Cochrane report released in the fall found that people in areas with fluoridated water had on average fewer decayed, missing, or filled teeth than those in non-fluoridated areas, but the reduction is less dramatic after the widespread introduction of fluoridated toothpastes in the mid-1970s.

Another recent analysis—published in JAMA Pediatrics earlier this month and first released last year by the National Toxicology Program—focused on fluoride and neurodevelopment. It showed a link between exposure to high levels of fluoride and lower IQ in children. It’s important to note that the fluoride levels in the studies analyzed, which were all conducted overseas, was at or above 1.5 milligrams per liter, more than double the amount in US water systems. While the research on lower levels of fluoride and neurodevelopment is more limited, recent studies out of the US and Australia show that fluoride at the levels found in US water systems is not associated with lower IQ in kids, and more research is underway.

When we take everything into account, we can conclude that current fluoride levels in US water supplies are safe, but that the dramatic impact of water fluoridation on cavity incidence and prevalence has gone down. While it’s not as effective, it’s still effective.

We should continue to evaluate emerging research and refine guidelines to ensure safety. The regulation of fluoride concentrations at 0.7 milligrams per liter—the current standard—ensures the population benefits from cavity prevention without exposure to levels associated with cognitive or neurodevelopmental risks.