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Gluckman Review downplays risk to IQ from fluoridation

New Health NZ Inc

Media Statement

26 February 2015

Gluckman Review downplays risk to IQ from fluoridation

The panel convened in 2014 to review water fluoridation has been forced to quietly amend an error in its report about the effects of fluoridation on IQ following international peer review. In an open letter to co-commissioners of the report, Sir Peter Gluckman and Sir David Skegg, New Health NZ Inc calls on the panel to explain why they consider the significantly more negative impact of fluoride on IQ to be insignificant.

The 2014 Report, entitled “Health Effects of Water Fluoridation: a Review of the Scientific Evidence” incorrectly stated that the adverse impact of fluoride exposure on IQ was less than one IQ point, but has now been amended to recognise that the established scientific evidence supports a reduction of seven IQ points. However, the Report fails to explain the implications of such a shift and appears to dismiss it as trivial.

New Health NZ Inc Chairman David Sloan says the potential impact of losing seven IQ points on a population basis is worrying, especially given that the scientific research that the Report selectively cites (Choi et al) concludes that “a shift to the left of IQ distributions in a population will have substantial impacts, especially among those in the high and low ranges of IQ distribution.”

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“In other words, the potential impact is significantly fewer geniuses in society and significantly more people who have low IQ with all the associated macro impacts of that in terms of economic and social development,” says Mr Sloan.

The scientific evidence, while it acknowledges some remaining uncertainty, is sufficiently robust now to conclude that increased fluoride intake reduces IQ. While it is not known what the impact is on IQ at current levels of fluoridation in New Zealand, there is enough uncertainty about the risks to mean that fluoridation must be revisited.

“Given the scientific uncertainty and the irreversibility of IQ loss, we need to take a precautionary approach and people deserve to be properly informed about the real benefits and risks of fluoridation,” says Mr Sloan.

Dr Paul Connett, advisor to New Health NZ Inc and lead author of “The Case Against Fluoride”, who is currently touring New Zealand, says “There is a terrible irony here. The last children who need to lose IQ points are children from low-income families and they are precisely the children being targeted by fluoridation programmes. This is a classic case of good intentions gone awry.”

From parents’ perspective and from a public policy perspective, the question is whether the purported benefit of mass water fluoridation – on average saving children half a filling at the age of 12-13 – outweighs the risks of reduced IQ.

Dr William Hirzy, former senior scientist at the US Environmental Protection Agency, and touring New Zealand with Dr Connett, says “A major study published two days ago in the UK adds even greater urgency to this issue. Women have been found to have a 30% greater chance of succumbing to hypothyroidism (underactive thyroid gland) in communities with fluoride levels above 0.3 parts per million (ppm) (the average fluoride levels in fluoridated areas in New Zealand are 0.85 ppm).

“It is well known that women who have lowered thyroid function give birth to babies with neurotoxic deficits which translates into lowered IQ when measured in childhood. In China, in areas with low iodine intake children were found to have lowered IQ with fluoride levels in the water as low as 0.88 ppm fluoride (Lin et al, 1991).”

New Health NZ Inc Chairman David Sloan added, “We need to take a more intelligent approach to public health. Let’s focus on the real cause of tooth decay which is poor diet and poor oral hygiene. Educating kids and parents about diet and toothbrushing is the answer together with other targeted oral treatments.

“Mass medication with a highly toxic industrial waste product that may be contaminated with arsenic, mercury and lead, and potentially reduces IQ across a population, is not a civilised response.

“Protecting the health of citizens is far more important than protecting the government’s fluoridation policy,” says Mr Sloan.


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