Claim: Fluoride is a poison (HHS Secretary RFK Jr.)

[Mendel]

Be cautious, please, in assuming motivations. Unless you are one of them mind readers!

I'm not sure Joel understands why I disagree.

 

[joel_yancey]

You started this thread with a meta-study that claimed most of the rearch on this issue is biased.

I don't have a dog in this fight. I am looking at evidence objectively. In my view the 2025 meta-analysis was not at all compelling.

I told you exactly why you are wrong, and how you misunderstood the "conclusions" section.

And I told you how you misunderstood it.

I do not think it'd be a good idea for government to not have health experts whose knowledge informs health regulations.

Of course we should have those. That's why we're talking about this quack RFK Jr. who is not a health expert.

 

[Mendel]

I don't have a dog in this fight. I am looking at evidence objectively. In my view the 2025 meta-analysis was not at all compelling.

At this point, I usually recommend that people re-read the thread, but they never do, and the discussion spirals down the drain.

My point was that most of the research is at high risk of bias.
2023 Italian paper, from the OP: "the overall RoB was "high" in 11 studies, "moderate" in 19 studies, and "low" in 3 studies. "
@joel_yancey , OP, paraphrasing 2023 paper: "the vast majority of studies on this topic have high likelihood of bias."
2025 NIEH paper (JAMA): "Fifty-two studies were rated high risk of bias and 22 were rated low risk of bias."

Now, I do not understand why you reply to my statement "most of the rearch on this issue is biased" with "the 2025 meta-analysis was not at all compelling", when you agree with it (and me) on this point.

And I told you how you misunderstood it.

I do not see substantive replies from you on my posts #32 and #37 .

What we have here is a number of studies that show an inverse correlation between two different fluoride exposure measures and IQ scores. I want an explanation for this well documented effect. It seems foolish to not consider that long-term fluoride exposure may be neurotoxic.

Your counter-arguments are
• there may be a common cause for both fluoride exposure and IQ scores
• the markers used to assess fluoride exposure are unsuitable
• IQ scores are unsuitable to assess neurotoxicity

The thread has not provided evidence for any of these arguments, I see only speculation. And with respect to the measures for fluoride exposure and neurotoxicity, I don't see better suggestions; and in their absence, the only choice we have is to use them or to ignore the issue.

JAMA provides two editorial comments with the 2025 paper:

Article:

Time to Reassess Systemic Fluoride Exposure, Again

Caution Needed in Interpreting the Evidence Base on Fluoride and IQ

Source: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2828425

JAMA requires a (free) account to read them.

If I wanted to critique the methods in depth, I'd probably focus on the Canadian studies (and maybe the Danish one), if they're rated at "low risk of bias".

 

[Ann K]

Children, children, go to your rooms if you can't play nicely!

OT, but - In today's news, another familiar medical [snip] enters the arena:

Ron DeSantis believes Dr. Joseph Ladapo would be a "fantastic selection" to helm the Centers for Disease Control and Prevention. The recommendation is timely, as former Congressman Dave Weldon did not move forward in the process due to insufficient support from Senate Republicans.

If this feels familiar, it's because DeSantis has done this before. He pushed for Ladapo's nomination for the head of the Department of Health and Human Services before Robert Kennedy Jr. was nominated.

In turn, Ladapo campaigned for DeSantis during the last presidential race, and strongly suggested he wants First Lady Casey DeSantis to be Governor more recently.

Ladapo, who is the second Surgeon General under the DeSantis administration and is also a Professor of Medicine at the University of Florida, has been vocal about vaccines and their side effects, among other issues, since he took over for Scott Rivkees during the pandemic.

In addition to repeatedly making the case against mRNA vaccines for COVID-19, Ladapo more recently has offered cautions about flu and measles shots.

https://floridapolitics.com/archives/726420-ron-desantis-wants-joseph-ladapo-at-cdc/
On "X":
@BillyCorben
·
Ladapo touted hydroxychloroquine w/Stella "Demon Semen" Immanuel who says gynecological issues are caused by women having sex in dreams with demons, scientists make vaccines to stop religion & gov't is run by aliens. Twitter, Google, Fbook removed their video for misinformation.

 

[Mendel]

Ladapo touted hydroxychloroquine w/Stella "Demon Semen" Immanuel who says gynecological issues are caused by women having sex in dreams with demons, scientists make vaccines to stop religion & gov't is run by aliens.

Dunno, doesn't he look like a DEI hire to you?
I'll show myself out....

 

[joel_yancey]

I am 31 years old and I have never had a cavity in my life. I attribute that in large part to a well-fluoridated water-supply, because science shows that is true. It is healthy to have confidence in your smile. RFK Jr. is a quack. he is a conspiracy-peddling attorney masquerading as a health professional. Next I would like to examine his claim, that WiFi causes cancer.

 

[Nemon]

I am 31 years old and I have never had a cavity in my life

This is an n=1 anecdote, if true at all, (strictly speaking, it is irrelevant here because it is not verifiable for us) while the next statement leads to generality:

I attribute that in large part to a well-fluoridated water-supply

If your logic is correct, no one should have cavities in their teeth who had the same exposure to fluoride. Correct me if I am mistaken here.
And that one is a bold statement - in terms of understanding science and even more so in view of the fact that fluorides are actually toxic:

because science shows that is true.

 

[FatPhil]

If your logic is correct, no one should have cavities in their teeth who had the same exposure to fluoride. Correct me if I am mistaken here.
And that one is a bold statement - in terms of understanding science and even more so in view of the fact that fluorides are actually toxic:

You're mistaken. His logic would make you expect fewer cavities amongst those who have had the same exposure to fluoride than in an otherwise-equivalent sample of people with lower exposure to fluoride. You have committed the fallacy of presuming the thing that is better must be perfect, which isn't the case, and fortunately hasn't been claimed.

And on your final point, fluorides are only toxic when retained in excess of quantities which are considered non-toxic. However, that statement can be applied to anything.

 

[Nemon]

@FatPhil
I cannot accept this criticism in this form. Now we can haggle over the logic of various statements. I don't intend to do that. But you can't leave it the way he wrote it. That's obvious.

Fluorides are fundamentally toxic, of course gradually and dose-dependent. In which doses they can be held responsible for which benefits and which damage cannot be determined with any degree of certainty, I would assume. Or are the undisputed results of many years of experimental studies with humans available? Is there any real evidence for the benefit to tooth enamel after weighing up all the risk factors of fluoride? All guidelines in this regard can only be based on estimates and are nothing more than opinions expressed by consensus panels. This means that we are now in the field of politics (with all the problems regarding independence, conflicts of interest etc.) and no longer science. Therefore, the argument here was very ill-considered, not only with personal anecdotal evidence, but also in combination with "science" as a whole, and the statement with the smile is also irrelevant. I merely advocate arguing prudently and stringently and with a more rigorous standpoint on science.

 

[Ann K]

@FatPhil
I cannot accept this criticism in this form. Now we can haggle over the logic of various statements. I don't intend to do that. But you can't leave it the way he wrote it. That's obvious.

Fluorides are fundamentally toxic, of course gradually and dose-dependent. In which doses they can be held responsible for which benefits and which damage cannot be determined with any degree of certainty, I would assume. Or are the undisputed results of many years of experimental studies with humans available? Is there any real evidence for the benefit to tooth enamel after weighing up all the risk factors of fluoride? All guidelines in this regard can only be based on estimates and are nothing more than opinions expressed by consensus panels. This means that we are now in the field of politics (with all the problems regarding independence, conflicts of interest etc.) and no longer science. Therefore, the argument here was very ill-considered, not only with personal anecdotal evidence, but also in combination with "science" as a whole, and the statement with the smile is also irrelevant. I merely advocate arguing prudently and stringently and with a more rigorous standpoint on science.

Of course there are grey areas. Fluoride in the water does not equate to fluoride ingested by any individual, nor does it take into account the various levels of dental hygiene of individuals. But you seem to demand precise statistical values for the good it has done, while hand-waving away similar statistics for any adverse effects it might have had.

 

[Mendel]

Is there any real evidence for the benefit to tooth enamel after weighing up all the risk factors of fluoride?

Good question.

Source: https://fluoridealert.org/studies/caries01/

sBut you seem to demand precise statistical values for the good it has done, while hand-waving away similar statistics for any adverse effects it might have had.

After reading that fluoride-critical page, I'll take any statistics.

 

[Mendel]

And on your final point, fluorides are only toxic when retained in excess of quantities which are considered non-toxic.

Please read https://www.metabunk.org/threads/claim-fluoride-is-a-poison-hhs-secretary-rfk-jr.14073/post-339258 , it has sources.

Your logic amounts to "a knife is only sharp when you use to cut something".

 

[Mauro]

@FatPhil
I cannot accept this criticism in this form. Now we can haggle over the logic of various statements. I don't intend to do that. But you can't leave it the way he wrote it. That's obvious.

But the first test an argument needs to pass is to be logical: if its logic is faulty it automatically fails. This is what @FatPhil pointed out: your statement in post #47 uses a faulty logic, so it's wrong, so it's useless in advancing your cause. No haggling here, just a basic sanity check.

Fluorides are fundamentally toxic, of course gradually and dose-dependent.

Too much fluoride is poisonous (https://en.wikipedia.org/wiki/Fluoride_toxicity) or even quickly lethal, but fluoride is also an essential micronutrient which is needed by the human body to work properly, so too little fluoride is dangerous too, for instance resulting in a greater incidence of dental cavities (which are not only a painful and costly nuisance, but with some bad luck they can become a dangerous-to-lethal source of infections). So there is an optimal level of exposure to fluorine, not too much, nor too little, and if the natural sources of fluorine are not enough it makes sense to fluorinate water, as it makes sense to remove fluorine from water if it's too high.

Being toxic both at high and low levels is true for many other substances, just for example Vitamin D is dangerous when it's too high (Vitamin D toxicity) and when it's too low (Vitamin D deficiency)

In which doses they can be held responsible for which benefits and which damage cannot be determined with any degree of certainty, I would assume. Or are the undisputed results of many years of experimental studies with humans available? Is there any real evidence for the benefit to tooth enamel after weighing up all the risk factors of fluoride?

@Mendel already answered you. Your assumption is bad: benefits and damages have been studied extensively and they are continuosly reviewed and updated. I'm surely no expert in water fluorination, but I checked Google Scholar (https://scholar.google.com), searched for 'water fluoridation' and found about 112K hits:

Then I tried Nature (https://www.nature.com/search?q=water+fluoridation&journal=) and found another trove of articles.

And what I learnt (let me summarize, hoping I got it right, just skimmed the surface) is that studies before 1975 found a consistent benefit in caries reduction which supported water fluoridation (in zones where fluoride content is not enough already), but now dental hygiene has improved and fluoride is being routinely added to toothpastes, so the incidence of caries has decreased overall (see also @Mendel's graph) and at the moment it's unclear if going on to fluoridate water is convenient or not (ie. see Has the decline of dental caries in English children made water fluoridation both unnecessary and uneconomic?).

But notice how these conclusions are reached: not by emotional appeals (fluorine is toxic! anathema!) or non-sequiturs (fluoride is toxic, then adding fluoride to water is always bad, even if just a little fluoride is not toxic and prevents caries) but through careful scientific study (the incidence of caries has declined and it might not be worth to go on with fluoride supplements to prevent them, expecially of one already uses a fluorinated toothpaste).

All guidelines in this regard can only be based on estimates

Of course, but as any other thing in this world: we can only rely on estimations (and probabilities). So this has no bearing on the debate: it is true both if fluoridation is good and if fluorination is bad.

and are nothing more than opinions expressed by consensus panels.

Not at all. They are (in the fluorination case) careful statistical studies made by competent (and competitive) people, who are never satisfied by the consensus (it's boring) but continuously question themselves and their (and their colleagues') results, and adapt (always in the fluorination case) to a changing world.

This means that we are now in the field of politics (with all the problems regarding independence, conflicts of interest etc.) and no longer science.

And here you're right: science is not politics, and vice-versa. When laws need to be enacted and funds allocated it's a job for politicians, not for scientists. Science can (and must) inform politics, and politicians would better heed what scientists say, because scientists get it right much more often than not. But science cannot substitute for politics, while politics should not, really not, interfere with science and/or nurture anti-scientific stances. It will be costly, a lot.

 

[Nemon]

so too little fluoride is dangerous too, for instance resulting in a greater incidence of dental cavities

I am opening up another aspect of the topic here: you have the wrong idea about certain things. The cause of tooth decay is first and foremost the intake of sugar/carbohydrates. For my part, I consume almost none of it, max. ~20g of carbs/day. In my opinion, this should be the message that the health system sends out: "Don't eat sugar!" Unfortunately, it doesn't fit in with the food pyramid as it was invented. But I don't want to go into that here, it would be OT.

@Mendel already answered you. Your assumption is bad

I don't see that in the graph he showed above.

As for the rest, thank you for your detailed response. But unfortunately I can't go into this any further these days due to time constraints. But I would have to do so in order to explain my point of view more clearly and in detail. That's why I have to bow out.

 

[FatPhil]

Please read https://www.metabunk.org/threads/claim-fluoride-is-a-poison-hhs-secretary-rfk-jr.14073/post-339258 , it has sources.

Your logic amounts to "a knife is only sharp when you use to cut something".

I find a tautology to be a more useful statement than one that implies that theoretical potential for harm is actualised harm, which is at best misleading. In particular when low exposure is known to be more beneficial than zero exposure, which is the case for fluoride.

We have a value for the LOAEL; stay in that regime - which most people can do because we're largely in control of what people are exposed to - and you're fine.
The toxicity guidelines are intended to be as guidance for people who do *not* have that exposure so regulated, such as people who work in labs or fabs with chemicals normies wouldn't ever typically encounter.

To stretch your ill-fitting analogy almost to breaking point, it matters not how sharp knives are when they're all locked away in the museum display cabinet.

 

[deirdre]

No haggling here, just a basic sanity check.

only disliking your comment due to the "sanity" attack. the rest was good.

I don't see that in the graph he showed above.

those two sentences dont really go together. The first part, 'Mendel already showed you' is only referring to your last question in the quote. ie, No, there seems to be no benefit today to fluorinating water. (and since like 1975).

https://www.researchgate.net/figure...-and-non-fluoridated-countries_fig2_230607918

 

[Mauro]

only disliking your comment due to the "sanity" attack.

I'm sorry, but I did not use 'sanity' in the sense of attaching (and attacking) it to any person, but in the technical sense of making the most basic and quick tests on something to see if works or not. Ie. when I write software I include 'sanity checks' (marked as such) to be sure everything is working properly:

Or, when I was working in engineering we did as many 'sanity checks' as possible on any idea we had, to avoid wasting time on things who could not possibly work.

Sorry for the misunderstanding, I see now how 'sanity check' can be interpreted negatively, but that was not the intention. Cheers!