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It is now accepted that fluoride is a neurotoxin

POSTED: 10 July 2018

It is now accepted that fluoride is a neurotoxin. What is not known is at what dose. Last year a landmark study, carried out by researchers from top universities such as Toronto, MaGill, Michigan and Harvard was published in Environmental Health Perspectives. This was a multi-million-dollar funded by the US Government. It found children exposed to fluoride in utero have lowered IQ. Should we be worried?

The study, Bashash et at, looked at the fluoride urine levels of pregnant Mexican women and then compared the IQ of their offspring. They found that for every 0.5 mg/L of fluoride, there was a subsequent reduction in the IQ of their child by around 2 to 3 IQ points. In Mexico the water is not fluoridated but they do have fluoridated salt. However, where this study provides a really safe platform to make judgement, is that it was looking at total fluoride exposure. It does not matter where fluoride comes from, as it is the total bodily load that is important.

The only study that has looked at the actual fluoride load experienced by New Zealanders, one of the few studies in the world, is a study carried out by researchers at Massey in Palmerston North. They also tested the fluoride urine levels of pregnant women and found just about exactly the same levels of fluoride. Median urinary fluoride concentration was 0.82 (0.62, 1.03) mg/L. Median urinary fluoride concentration of the Mexican women was 0.87 (0.82, 1.10) mg/L.

There are now a total of 59 human studies that have looked at fluoride and neurotoxicty. Of those, 53 have found fluoride to have an adverse effect. The only fluoride-IQ study carried out in New Zealand is the Broadbent study that was published in 2014. It found no difference between children growing up in fluoridated Dunedin compared to children growing up in nonfluoridated Mosgiel. This study was applauded because it used data from the world-renowned Dunedin Longitudinal study but it has also been severely criticised for a number of reasons. One being that there were very few participants not ingesting either fluoridated water or fluoride tablets, 56, compared to 973 on either fluoridated water or taking fluoride tablets.

In 2012 a Harvard meta-analysis of 27 fluoride-IQ studies was published in the Lancet. These studies were from China, India, Iran and Mexico where the fluoride levels in the water were mostly higher than we have in New Zealand. The meta-analysis found a difference of nearly half a standard deviation between the low and high fluoride areas. In IQ studies, a standard deviation is 15 IQ points, so this meta-analysis found a mean loss of 7 IQ points.

These studies were referred to in the 2014 New Zealand Report on Fluoridation by the Chief Science Advisor and the Royal Society of New Zealand. However, the authors Sir Peter Gluckman and Peter Skegg mistakenly thought the drop in IQ was less than one IQ point and therefore had concluded “Recently there have been a number of reports from China and other areas …that have claimed an association between high water fluoride levels and minimally reduced intelligence (measured as IQ) in children.…the claimed shift of less than one IQ point suggests that this is likely to be a measurement or statistical artifact of no functional significance”. Once this error was pointed out to them, they changed the statement to say “…the claimed shift of less than one standard deviation suggests that this is likely to be a measurement or statistical artifact of no functional significance.” The fact they did not change the conclusion has been heavily criticised by fluoridation opponents.

A drop of 5 IQ points will halve the number of geniuses and increase by 50% the number of mentally impaired.

There also hundreds of animal studies detailing fluoride’s adverse effect on the brain.

For more information please see the Fluoride Alert website.


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