[lukan]

But flakes of gold are not associated with a lower IQ in children.

"The NTP monograph concluded, with moderate confidence, that higher levels of fluoride exposure, such as drinking water containing more than 1.5 milligrams of fluoride per liter, are associated with lower IQ in children."

https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/...

So it is also not clear, if the lower concentration typically found also has this effect.

"It is important to note that there were insufficient data to determine if the low fluoride level of 0.7 mg/L currently recommended for U.S. community water supplies has a negative effect on children’s IQ."

But the solution of just using (cheap) Fluor in toothpaste to apply the Flour where it should go - to the teeth and not the stomach, sounds smarter to me.

[kelnos]

So in other words, 0.7mg/L fluoridated water is also not associated with lower IQ in children. That study did not prove it safe, but it did prove it unsafe, either.

[lukan]

That study did prove, that too much flouride is not good for intelligence.

And there are other sources besides water from the tap, so I don't think it is intelligent to raise the base level, when the option of local applying exists. What is wrong with toothpaste?