Link: https://twin-cities.umn.edu/news-events/fluoride-drinking-water-does-not-harm-childrens-iq

Study.

The study, published in PNAS, examined Wisconsin state testing records, archival information about when Wisconsin cities began to fluoridate their water, and data from the Wisconsin Longitudinal Study, which has followed a random sample of 10,317 high school seniors from 1957 through 2026. Key findings include:

• There is no evidence supporting a connection between community water fluoridation and children’s IQ.
• There is also no evidence supporting a connection between community water fluoridation and cognitive functioning at various points later in life.
• Findings confirm evidence published in previous research which also used a national sample, but considered school achievement test scores instead of actual IQ scores.

I'm going to post this again, because everyone needs to fucking understand that science is studying results and a process:

What about autoimmune diseases and inflammation? It looks like there might be a link, but they haven't studied it enough.

Based on the body surface area of humans and animals, and considering the metabolism and absorption of fluoride in rats, according to calculations, the WHO’s safety threshold for fluoride intake from drinking water (1.5 mg/L) corresponds to a fluoride concentration of 10 mg/L in the drinking water of rats. After 1 week of acclimatization, the 150 rats were randomly assigned to 5 groups (n = 30) and provided with drinking water containing 0, 10, 25, 50, or 100 mg/L of fluoride. Although 50 and 100 mg/L are not equivalent to the doses humans are exposed to in natural environments, they are commonly used in animal models of fluorosis and have been widely demonstrated to be robust in rat models of fluorosis [35,36,37]. According to the exposure mode and time of fluoride, it can be divided into three modes: fluoride treatment for 12 weeks (12 w), fluoride treatment for 24 weeks (24 w), and fluoride treatment for 12 weeks and 12 weeks of improve water(12 w12 wi) (Table S1). Rats were euthanized with isoflurane anesthesia at the end of the breeding period.

https://www.mdpi.com/2305-6304/13/2/95

That doesn't clearly communicate the levels of fluoride necessary to show such a response.

That's the part where they need to study it more.

Or they could have just shared that information from the study.

But shouldn't it? That's what is claimed. But I'm certain enough there's a large enough populace that doesn't drink tap water to confound results.

Huh? It's there for cavity prevention.

Read any scientific literature?

Yes, regularly.

Are you having a stroke?

Damn it. I was gonna come in here and be like, "Ah, that's what big fluoride wants you to think, sheeple!"

You know, like a crazy person.

But it turns out the actual crazy people who truly believe that stupid shit are already out in full force.

"We gave rats 6.66 times more than humans are exposed to and bad stuff happened."

That's really not a good methodology.

I'll accept the null answer.

🍞🔥

Obligatory

No one is mentioning that it calcifies the pineal gland which prevents natural secretion of DMT as well as the ability to use our minds to travel.

The usefulness of fluoride is pretty well established at this point. If you have new data, please share it.

This comment section is so bonkers, I can't tell if you're being sarcastic or not.

Not at all. It’s why I switched to a zero water filter. Drinking water with fluoride messes with our ability to reach our full potential, and at a time when that’s the most possible thanks to knowledge of the most effective techniques to do so.

Dammit. Why have I been drinking all this water then?

Damn I’ll have to find something else to blame

Yeah. Flouride consumption isn't an issue, but fearing flouride despite the studies, that's a red flag.

For you information, that "zero water" filter is not that great for your health. It removes all the minerals and other bits in the water, and water without those minerals is not as good for you. Ultrapure water can absorb some of the minerals in your body, which obviously isn't a very good thing.

Also, fluoride in the water is the opposite of bad, it's good for your teeth. It's in toothpaste for a reason! There is no reasonable evidence that fluoride causes any major health problems, in fact, the fluoridation of water is dubbed as one of the largest public health accomplishments in a while. In addition, the fluoride added to water is miniscule, tiny, far far too low in concentration to be toxic. It also occurs in plenty of foods naturally too (fruits, seafood, spinach, etc.)

Some more information of fluoride:

https://my.clevelandclinic.org/health/treatments/11195-fluoride

https://www.cdc.gov/oral-health/prevention/about-fluoride.html

https://www.sciencedirect.com/science/article/abs/pii/S000291652334718X

copying my answer from a different comment relating to fluoride:

Fluoride in the water is the opposite of bad, it's good for your teeth. It's in toothpaste for a reason! There is no reasonable evidence that fluoride causes any major health problems, in fact, the fluoridation of water is dubbed as one of the largest public health accomplishments in a while. In addition, the fluoride added to water is miniscule, tiny, far far too low in concentration to be toxic. It also occurs in plenty of foods naturally too (fruits, seafood, spinach, etc.)

Some more information of fluoride:

https://my.clevelandclinic.org/health/treatments/11195-fluoride

https://www.cdc.gov/oral-health/prevention/about-fluoride.html

https://www.sciencedirect.com/science/article/abs/pii/S000291652334718X

Water filters are still important*, just get a regular one that focuses on removing the bad stuff (lead, arsenic, that sort) rather than removing EVERYTHING

*if your tap water is unsafe to drink

copying my answer about fluoride, again:

Fluoride in the water is the opposite of bad, it's good for your teeth. It's in toothpaste for a reason! There is no reasonable evidence that fluoride causes any major health problems, in fact, the fluoridation of water is dubbed as one of the largest public health accomplishments in a while. In addition, the fluoride added to water is miniscule, tiny, far far too low in concentration to be toxic. It also occurs in plenty of foods naturally too (fruits, seafood, spinach, etc.)

Some more information of fluoride:

https://my.clevelandclinic.org/health/treatments/11195-fluoride

https://www.cdc.gov/oral-health/prevention/about-fluoride.html

https://www.sciencedirect.com/science/article/abs/pii/S000291652334718X

According to Wikipedia (I know, not the most accurate source. I just needed a quick statistic) the U.S. has a fluoride level of 0.7 mg / L since 2015. Poking around for other countries, it looks like 0.7-1.2 mg / L is the range that most countries add to their water supply.

For reference, the WHO recommends 1.5 mg / L as the upper limit. Additionally, in many places, the groundwater has fluoride levels a bit higher than that.

I mean, its fine - but it just isn't overly meaningful for how we make decisions as individuals. But to design a scenario where we would absolutely see an effect is valuable to see if we should invest more money into larger studies.

as well as the ability to use our minds to travel.

This comment has big "teleport to Waffle House" energy.

I’ve survived over half a century without a water filter? For half of that, I was on a well.

Water filters are good when they filter out something you know is in the water that shouldn’t be.

Better teef

Our ability to reach our full potential.

Now I know you are just memeing.

Fuck Utah

You appear to be referencing this study. You would need to drink 21.5L/day of fluorinated water (standard 0.7 mg/L of fluoride) for this to apply to you.

Oh, and you’d also need to be a duck.

Unfortunately, I've long since reached my full potential.

Proud Flint resident right here ^

Got it, I edited my comment

They're also good when they filter out something you don't know is in the water but shouldn't be. You ever get that well water tested? Did that test include PFAS?

That well water got tested on a regular basis. It didn’t include PFAS because nobody tested for PFAS back then.

However, most filters today don’t filter PFAS. A good reverse osmosis filter will, or distillation. Problem with distillation is that it filters out all the good stuff too, so then you have to fortify your water.

Also, they’re pretty useless when they filter out beneficial minerals but miss the thing you didn’t know about that’ll kill you.

Eh the first major study in fluoride, the Grand Rapids study would never hold up to today’s standards. It was not a blind study and cavity detection is subjective.

Also drinking water is a poor way to deliver fluoride. The mechanism of action requires physical contact with your teeth to work. Toothpaste and mouthwash would be a better option and reduce consumption. To my knowledge, there hasn’t been a modern large scale study conducted looking into different delivery methods. We do have some evidence comparing countries that don’t fluoridate but still have low cavity rates.

And while rare, fluoride allergies do exist.

It can also be difficult to dose.

Ok?

Seems about 20 people, including you, didn't get it.

So here's what I was thinking earlier:

If you feed a pig sweets. What happens?

Their teeth rot. Same for humans.

If an animals teeth are rotting, oh boy. Guess what? I mean science will greet you with many associations (I'm sure some are causal)... Including heart disease, cognitive impairments, chronic inflammation, infection, carries, abcesses, etc.

Long story short, you really don't want to eat that animal. And I imagine you really don't want to be that animal.

Really short: shit breath often leads to a shit head.

So.... if fluoride is so great... Apparently. So why doesn't this show up, if it's so great?

I would expect a positive association, based on the hype. This says it found none.

So what's the benefit then?

Bad oral hygiene is associated with IQ decline. So if fluoride is helping alleviate that, where's that data?

This study disagrees with you.

No significant difference.

You might wanna double check those p-values.

Wooosh

Fluoride doesn’t impact your IQ.

Whatever you’re on … does.

That is all.

Other studies disagree with that conclusion.

I mean... I can take any IQ test against you and I can tell you what I'm going to get... 98th percentile. That's 130-140. Not perfect. But certainly above average.

Will you even break a hundred?

the first major study in fluoride, the Grand Rapids study would never hold up to today’s standards. It was not a blind study and cavity detection is subjective.

There has been many more studies on fluoride, none of which have shown that that the low concentrations of fluoride added to drinking water has any negative health effect. Not just the one, always check multiple sources!

Also drinking water is a poor way to deliver fluoride

It depends on the area you're dealing with. In some countries, it's more cost effective to put fluoride in the water supply, while in others, fluoride toothpastes are more effective. In Germany, they put fluoride in iodized salt!

So what's the benefit then?

Protection against tooth decay? I'm not sure I understand your point. That is a pretty big health benefit, I think, not sure why you think it's not a positive effect. There are plenty of studies as to how fluoride (in the water or as toothpaste) can protect against cavities.

I will reiterate my point that fluoride levels in water is too low to be dangerous, as the WHO recommends a maximum of 1.5 mg / L for fluoridation of water, while most countries that implement it use a concentration of 0.7-1.2 mg / L. Additionally, fluoride is also naturally present in many fruits, seafood, etc. as well as many groundwater sources that are perfectly safe to consume.

edit: I think I understand what you are talking about. Yes, fluoride does not increase nor decrease IQ levels. Its main job is to protect against tooth decay. But that is still a public health benefit, no?

I guess I'll reiterate. Many studies from early studies, after fluoridation became more common versus before, have found numerous benefits. Across the globe....

I think this study is more absence of evidence rather than evidence of absence.

Like.. Shit. Say a kid has a cavity do you think he's going to be focusing on his homework or his tooth hurting?