[nostrebored]

Your dentist is not an expert in this — that’s like saying the guy implementing your frontend is an expert in design. Yes, they’re working in the space, but their job isn’t understanding the whole system.

If you’re this deep on the appeal to authority train, the NIH released a report in the last year linking fluoride exposure to moderate drops in IQ with moderate confidence.

It’s probably not the worst thing in the world, but is definitely not inert.

[jandrewrogers]

I am competent on this particular subject matter, I have worked in fluorine chemistry and am familiar with the biology and medical literature of fluorine toxicity. The report made much weaker claims than people seem to think.

There is a very serious mechanism of action problem. Fluorine poisoning is a thing that happens. The observed effects and empirical evidence, as well as the mechanisms of action that cause them, are incompatible with any mechanism of action that supports the hypothesis that it causes brain damage. Basically, it would invalidate the entire history of actual fluoride exposure.

The other serious problem is that people are exposed to far more fluorine through what they eat than through water. What is special about trace levels in municipal water? And many parts of the world have far higher natural fluoride levels in their water than any municipal water supply with no evidence of adverse consequences. This has been studied many times in many countries! In fact, the only consistent correlation with naturally high fluoride levels is better cardiovascular health (for which there is a known mechanism of action).

This notion that trace levels of fluoride in some municipal water is adversely impacting IQ based on thin evidence from the developing world is just the public health version of “faster than light neutrinos”. Someone thinks they measured it but it contradicts everything we know about the subject. The rational approach isn’t to discard everything we know without a hell of a lot more evidence.

I don’t think adding fluoride to municipal water does much these days but it also isn’t harming anyone.

[hayst4ck]

It also seems to mirror the rhyme with the vaccine "debate."

That debate is framed around being vaccinated vs the scare of "vaccine caused autism" (or myocarditis), but that frame is missing the risk of things like measles.

Likewise tooth decay is not only expensive, but it can have dreadful health consequences if left unaddressed. Missing teeth is also socially costly. Being poor or "ugly" or poor looking is a serious adverse health consequence. Imagine parents barely making ends meet or working multiple jobs. It's easy to imagine disadvantaged kids missing out on dental care.

I also explicitly remember reading multiple reports of poor tooth health correlating with dementia development. I've also read that serious infections of any sort can harm IQ.

[kelnos]

Sure, but we need to look at this from the other side, too. Does fluoridating water provide benefits? I think it's safe to say it did way back when we started doing it. But we didn't have fluoride toothpaste back then. Putting fluoride in the water is presumably more costly than not doing it. If it's actually providing benefits, and the risk of harm is below some very low threshold, then sure, let's keep doing it. But is it actually providing benefits?

[noodletheworld]

Dentists have to spend 8 years at school right? …and do various annual training to stay licensed?

I’d say that’s a reasonable sign of someone qualified to have an opinion.

I think you’re getting confused with a dental technician.

[jandrewrogers]

I would be really surprised if dentists had much expertise on the impact of fluorine on physiology or the mechanisms of action for its toxicity. They know what it does to your teeth, and maybe that it is known to have positive effects for cardiovascular health, but that is about the extent of it. The systematic effects on the rest of your body are outside their domain.

Chemists who work in fluorine chemistry on the other hand have to become experts on the biological effects of fluorine exposure. Small and seemingly innocuous exposures can do a lot of damage and kill you, though not in a way that lends any support to the idea that municipal fluoridation will harm you. If you do understand how it kills you (basically by being exceptionally narrowly focused on making free calcium ions and to a lesser extent magnesium ions biologically unavailable), it is hard to describe a chemically plausible scenario that somehow avoids this basic fact of chemistry. Fluoride behaves the same way outside the body.

Municipal water exposure is far below the noise floor for fluoride. Food has far higher levels of fluoride than municipal water and the body has ample excess calcium and magnesium to absorb the loss of bioavailability of a microscopic amount of those minerals. Humans consume calcium measured in grams per day, multiple orders of magnitude more than can be lost via municipal fluoridation. Natural dietary variation will have a far larger effect.

[petesergeant]

You don’t seem to understand the difference between public and private health.

Your dentist is well qualified to have an opinion on the effects of fluoride on your teeth.

They are poorly qualified to have an opinion on whether it should be added to the water supply at source.