They should? We’re not so sure about that.
Now, to be fair, Dr. Bicuspid didn’t come up with that message on its own. It came from the authors of a new study in JADA which looked at whether drinking fluoridated water leads to a lower risk of cavities for kids — at least among privately insured Massachusetts children.
We’re pretty sure you can guess what they found.
For Massachusetts municipalities deliberating fluoridation policies, our study results support the continued investment in fluoridation and are likely generalizable to other states. Policy makers can recognize fluoridation as a cost-effective preventive strategy with meaningful cumulative benefits across economic strata, particularly for teenagers. Dental care practitioners can confidently advise communities and patients about fluoridation’s ongoing value, even with widespread access to dental products. Our findings suggest that discontinuing fluoridation could result in increased restorative oral health care demands, elevating public and private health expenditures.
To explore the impact of community water fluoridation (CWF) on children’s dental health, the researchers analyzed private dental insurance claims for more than 35,000 Massachusetts children from 2016 through 2019. They identified whether the kids lived in fluoridated communities or not, and compared the number of restorations they received relative to the number of dental exams they had.
They also accounted for factors that might influence the results, including age, sex, household income, dental sealants, and professionally applied topical fluoride.
The results were pretty straightforward: The authors found that kids with fluoridated water had fewer fillings relative to how many dental exams they’d had. The association was stronger among kids who were at least 13 years old when they entered the study.
And that’s fine, so far as the findings go. Still, it’s a head-scratcher, figuring out how the authors got from “kids in fluoridated communities had fewer fillings” to “water should be fluoridated for everybody.”
The most obvious issue is that this was a study of children. Not adults. Not whole communities. Just children. Ages 1 through 16. Who had private dental insurance.
And that last detail matters. In at least one important respect, it was a relatively privileged group. The kids had private dental insurance and were using it. The authors themselves call attention to this fact, noting that most research has focused on publicly insured or otherwise disadvantaged populations. By studying privately insured children, they could see whether the apparent benefits of fluoridation extended to children with greater access to dental care and other preventive resources.
According to their findings, they did. But it still tells us only about kids — even as children today may be getting less benefit from fluoridated water than previous generations, according to a 2024 Cochrane review. That same review found no eligible studies that addressed decay outcomes in adults.
Yet the thing about CwF is that everyone who drinks it is exposed to fluoride, regardless of age or cavity risk, whether or not they may benefit, whether or not they want it. .
Also notable is the fact that tooth decay wasn’t directly measured in the current study. It measured dental work as recorded in insurance claims. Fewer fillings may certainly reflect less decay, but the two aren’t interchangeable. A cavity is a disease finding. A filling is a treatment decision.
Then, of course, there’s the fluoride itself. Although the research team knew which participants had professional fluoride treatments — the insurance records showed as much — they had no way of knowing how much fluoridated water an individual child actually drank or how much fluoride they got from toothpaste and other everyday sources.
Yet the authors still conclude that dentists can confidently recommend fluoridation for its “ongoing value, even with widespread access to dental products.” Nowhere are any of the potential risks of ingesting fluoride mentioned.
Since the September 2024 federal court ruling ordering the EPA to address fluoride risk, there’s been something of a parade of new studies and analyses like this one, all involving children and fluoridation. Often they’re treated as if they provide fresh evidence for the continued value of community water fluoridation, and we’ve explored a good number of them on our blog — here and here and here and here, for instance.
In each case, once you look more closely at what the researchers actually studied and found, the evidence doesn’t seem to carry quite as far as the conclusions drawn from it, whether those conclusions come from the researchers themselves or from the way their work gets translated for the public.
It’s not that these are necessarily bad studies. The problem is the leap from what they found to what we’re told those findings mean.
