50-year-old data used for invalid cost-benefit analysis of fluoridation

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KEY POINTS –

• Paper by Choi & Simon in JAMA Health Forum misrepresents the current science to produce grossly unreliable and invalid results, warranting its retraction and a warning notice for readers.

• The paper uses 50-year-old evidence while claiming to cite the latest evidence on fluoridation benefits and harms.

• Stopping fluoridation in the USA will NOT cause a large increase in cavities, according to the latest and most authoritative evidence.

• In glaring double standard, the paper dismisses the stronger evidence of fluoride neurotoxicity and its costs while relying on outdated, low-quality evidence of dental effectiveness.

• Fluoridation proponents are relying on evidence from their grandparents’ time.

A widely publicized cost-benefit analysis of the effect of stopping fluoridation in the US [Choi & Simon 2025], claiming increased tooth decay and economic costs would result, has been challenged by scientific and dental experts calling for its retraction because of serious errors. The experts say Choi & Simon misrepresented evidence and based their analysis on outdated studies that are contradicted by the latest studies. In a letter sent to the editors and publisher of the journal JAMA Health Forum, the experts provided detailed reasons why the errors not only produce wildly overstated dental benefits for fluoridation but also grossly devalue the countervailing neurotoxic risks and the costs of dental fluorosis. The net result if Choi & Simon had followed the latest scientific evidence is that stopping fluoridation would actually produce the opposite of their conclusion. Tooth decay would not meaningfully increase, while the risk of lowered IQ would be eliminated, and the cost of objectionable dental fluorosis would be avoided. The net economic benefit of stopping fluoridation would be $100 billion per year from avoided child IQ loss, and $3 billion per year for the cost of repairing objectionable dental fluorosis. In contrast, a corrected estimate of the cost of any increase in tooth decay, which is of low certainty to begin with, is only $0.6 billion per year. Even if the 50-year old estimate of fluoridation’s effectiveness were used, it would only be saving $2 billion per year, much less than the economic cost of fluoridation’s harms. The experts also pointed out that:

An increase of $0.6 billion, when considered in the larger perspective of all dental spending in the US of $174 billion per year, represents only 0.3% of the total cost [ADA 2024]. Fluoridation is not playing a significant role in controlling the cost of dental care in the US.

The Choi & Simon paper uses 50-year-old evidence while claiming to cite the latest evidence on fluoridation benefits and harms.

They have grossly misrepresented what was found in their cited references: the 2024 Cochrane systematic review on fluoridation’s current (in)effectiveness [Cochrane 2024], and the 2024 National Toxicology Program systematic review on fluoride’s neurotoxicity [NTP 2024, Taylor 2025]. A cost-benefit analysis using the actual results of these systematic reviews shows that the dental benefits of fluoridation today are far smaller than 50 years ago and are greatly outweighed by health and economic harms from neurotoxicity and dental fluorosis—producing a huge net economic loss. The experts signing the letter argue this is the opposite of Choi & Simon’s conclusions and invalidates their paper, warranting its retraction.

While it may be difficult for long-time fluoridation advocates to believe, the fact is that water fluoridation today produces very little reduction in tooth decay. According to the Cochrane 2024 review, the widespread adoption of fluoridated toothpaste – a much more effective and targeted method of getting fluoride onto tooth surfaces – has made fluoridated water an anachronism. Water fluoridation might have helped in our grandparent’s time, but today offers little meaningful benefit.

The diminishing returns of fluoridation over the past 50 years, to a point where its benefit is so small as to be almost meaningless, is illustrated by these graphs that were included in the letter calling for the Choi & Simon paper’s retraction:

Figure 1. Greatly diminished effectiveness against caries is illustrated by plots showing diminishing difference between caries rates in non-fluoridated areas compared to those in fluoridated areas over the past 50 years. (A) Primary teeth (dmft), exponential trendline; for 21 studies in the United Kingdom at age 5 years; graph created from data extracted from Fig. 5 of Cochrane 2024 review. (B) Permanent teeth (DMFT), exponential trendline; for 7 studies in the United Kingdom at ages 11-15 years; graph created from data extracted from Fig. 6 of Cochrane 2024 review.

In glaring double standard, Choi & Simon dismiss the stronger evidence of fluoride neurotoxicity and its costs while relying on outdated low-quality evidence of dental effectiveness.

The scientific evidence for the neurotoxic risks from fluoride, especially loss of child IQ, has been rapidly accumulating, especially in just the last 10 years, while 50 years ago neurotoxicity hadn’t even been considered [NTP 2024, Taylor 2025]. The experts calling for retraction of the paper said:

To justify excluding neurotoxicity from cost-benefit calculations, Choi & Simon argue exposures in fluoridated US communities “… are not definitively associated with worse neurobehavioral outcomes,” citing an editorial by a dentist defending fluoridation and misrepresenting the NTP’s systematic review findings. The NTP, in fact, found lower IQ in 18 of 19 high-quality studies. For other neurotoxic effects like ADHD, 8 of 9 high-quality studies had worse outcomes with higher fluoride [NTP 2024, p xviii]. Importantly, 9 of 12 high-quality studies finding significantly worse IQ or other outcomes were at fluoride levels (water, urine, or total intake) in the same ranges as found with artificial fluoridation in the US [Taylor 2025 Supplement 1; and Attachment to this Letter summarizing data compiled in Taylor 2025]. Thus, the NTP found great consistency of significant adverse effects even among studies with exposures directly applicable to artificial fluoridation.

Choi & Simon also grossly underestimated the costs to repair the dental fluorosis caused by fluoridation in the USA.

The expert’s calling for retraction pointed out another serious error in the economic assessment:

While greatly overstating fluoridation’s benefit for reducing caries, Choi & Simon low-balled fluoridation’s adverse effect of dental fluorosis. The ostensible source for their assumptions about dental fluorosis risk is again the Cochrane 2024 systematic review, yet their assumed values are nowhere to be found in that review and are in fact directly contradicted by it. Furthermore, after grossly underestimating the number of fluorosis cases that warrant treatment, they also assign greatly underestimated dollar values for the treatment needed to repair the damage from fluorosis.

The cost per person, for the 12% of US children with fluoridated water who are expected to develop fluorosis of aesthetic concern according to the Cochrane 2024 review, is $2.8 billion per year [Cochrane 2024 p. 2, Osmunson 2024]. That far outweighs the $0.6 billion per year cost for the slightly increased number of cavities that might result from stopping fluoridation.

Fluoridation proponents are relying on evidence from their grandparent’s time, a time when lead paint and leaded gasoline were still being defended.

Our grandparents lived at a time when lead paint and leaded gasoline were blanketing the world in lead contamination producing a generation that was recently estimated to have lost more than 5 IQ points on average [McFarland 2022]. And for some of the most lead-poisoned children, it caused severe cognitive and behavioral problems, including violent behavior that was largely responsible for the peak in violent crimes in America in the 1990’s [Drum/MotherJones 2013a, Drum/MotherJones 2013b].

Just as much of the dental establishment that has championed fluoridation for over 75 years is defending fluoridation today, the lead industry defended itself by denying the health harms and claiming lead was a huge benefit to society because it allowed less expensive gasoline and more “hygienic” paint [Kitman 2000]. The industry even got some doctors to claim lead was not a problem at “low exposure” levels.

In your grandparent’s day, advertisements touted “LEAD helps to guard your health!” Today, fluoridation promoters are stuck in that same era. Fluoride is the New Lead.

The Choi & Simon paper misrepresents the current science to produce grossly unreliable and invalid results, warranting its retraction and a warning notice for readers.

The experts’ complaint to the journal that published the Choi & Simon paper concluded:

Considering the COPE Guidelines [Committee on Publication Ethics] and the massive publicity that has broadcast these unreliable findings on a topic of great public health consequence, we believe retraction is warranted, and a correction would be insufficient. We also urge JAMA Health Forum to issue an immediate Expression of Concern because of the seriousness of the errors and the major public health policy implications that are currently being debated across the US and abroad.