Effect of fluoridated water on intelligence in 10-12-year-old school children | Hacker News Reader

Effect of fluoridated water on intelligence in 10-12-year-old school children

ncbi.nlm.nih.gov

16 pointsunobatbayar8 comments

I used to worry a lot about the implications of studies like for people drinking fluoridated water, but at least in the SFBA, water is fluoridated to 0.7ppm, below the top threshold of the “low fluoride” group in this study

I admit that I am not expert in statistics, but the data they present seem to suggest that the highest scoring test group was in the medium exposure group? Also, something is not right with graph 2?

I came here because of that. I suspect it's mislabeled, since it looks like it would match the numbers if the labels at the bottom went low, mid, high instead of low, high, mid. But even more than that, I think the numbers demonstrate that some fluoride is better than none. And the low groups average is likely skewed by a single outlier, way at the top of the graph.

Poor study all around.

Important to note that many municipalities in Canada use hydrofluorosalicic acid to "fluoridate" their water supplies. Far more dangerous a substance, and fully legal under the Supreme Court of Canada's redefining of what "fluoridation" means in this country.

I don’t see why it needs to be added to the water at all instead of only in toothpaste. I’d rather have lots of people with rotting teeth than lots of low IQ people. It really makes no sense why it’s been pushed so hard and mandated.

“Water was collected from initially identified endemic fluoride regions according to the geological research of Government of India. “

Wonder why those areas were so fluoride endemic? First thought is factory waste running off into rivers?

In some areas fluoride is in the rocks and dissolves into the underground water. This is pumped up via wells.

Surface water, AKA rivers, starts with low fluoride in the mountains and it slowly accumulates as it flows down to the sea. Surface water almost always has less fluoride then well water though.

Some places naturally have water high in fluoride, due to the nature of the rocks and the water table.

That's how fluoride protection of teeth was discovered in the first place. People living in some parts of Colorado had mottled teeth from too much fluoride in the water. (It's now called "fluorosis".) Dentists noticed that such people also didn't get many cavities, and eventually tracked it to the composition of the water.

Turns out you can add enough fluoride to protect teeth without causing stains. Some places have way too much fluoride in the water. The staining appears to be the only problem.

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