Paul Connett and Vyvyan Howard have, through the local Fluoride Free New Zealand activist group, published an open letter addressed to NZ scientists and educators (see An Open Letter To NZ Scientists And Educators). It is strange to encourage scientific exchanges through press releases but if they are seriously interested in an exchange of informed scientific opinion on the research they mention I am all for it.
In fact, I renew my offer to Paul Connett for a new exchange on the new relevant research along the lines of the highly successful scientific exchange we had in 2013/2014 summarised in Conett & Perrott (2014) The Fluoride Debate.
Connett and Howard say they felt “let down” by the reception they received in their 2018 visit. But they should realise this sort of ridicule is inevitable when a supposedly scientific message is promoted by activist fringe groups with known funding by big business (in this case the “natural”/alternative health industry). The science should be treated more respectably and discussed in a proper scientific forum or via a proper scientific exchange rather than political style activist meetings.
It is this sort of respectable, informed and open scientific exchange I am offering to Paul Connett and Vyvyan Hoard.
Connett and Howard argue that there has recently been “a dramatic change in the quality of these [fluoride] studies.” I agree that new research occurs all the time and there is plenty of scope upgrading of the scientific exchange we had in 2013/2014 to cover that new research. Consideration of the new research requires the objective, critical and intelligent consideration scientists are well used to and this is not helped by activist propaganda meetings. So I encourage Connett and Howard to accept my offer. after all, if they are confident in their own analysis of this research what do they have to lose?
Inaccuracies in “open letter”
One can see an “Open letter” as displaying a willingness to enter into a proper scientific exchange. However, Connett and Vivyan’s open letter includes inaccuracies and misinformation on the new research which simply demonstrates that a one-sided presentation cannot present the research findings properly.
For example, they misrepresent the 2014 New Zealand fluoridation review of Eason et al (2014). Health effects of water fluoridation: A review of the scientific evidence. Even to the extent of mistaking the authors (not Gluckman & Skegg as they claim) and misrepresenting the small mistake made in the summary which was later corrected. That attitude does not bode well for the proper consideration of the research.
Connett and Howard concentrate on new research relating child IQ to fluoride intake but they ignore completely the fact that all the research comparing IQ in fluoridated and unfluoridated areas show absolutely no effect. I have summarised the results for the three papers involve in this table.
Instead, they concentrated on a few extremely weak relationships reported in a few papers. But even here they get this wrong – for example, they say there is “a loss of about 4 IQ points in offspring for a range of 1 mg/liter of fluoride in mother’s urine.” The paper they refer to (Green et al 2019) actually found no statistically significant relationship between child IQ and maternal urinary fluoride for all children considered. The relationship Connett and Howard mention was actually for male children (no relationship for female children or for all children) and was very weak. These sort of weak relationships are commonly found in epidemiological research and are usually meaningless. In this case, Connett and Howard have simply cherry-picked one value and misrepresented it as applying to all children.
Both the Green et al (2019) and Till et al (2020) papers Connett and Howard refer to suffer from selecting a few weak statistically significant relationships and ignoring the larger number of non-significant relationships they found for the data they investigated. Connett and Howard also completely ignored the new studies that don’t fit their claims. For example that of Santa-Marina et al (2019). Fluorinated water consumption in pregnancy and neuropsychological development of children at 14 months and 4 years of age. which showed an opposite positive relationship of child IQ with maternal urinary fluoride. Similar they ignored the large Swedish study of Aggeborn & Öhman (2020). The Effects of Fluoride in the Drinking Water showing no effect of fluoride on IQ but positive effects on oral health and employment possibilities in later life.
In conclusion, I reiterate that genuine open scientific exchanges do not take place via press release and activist meetings. However, the fact that Connett and Howard have issued an “Open Letter” could be interpreted as inviting others to participate in a proper exchange. I endorse that concept and offer Connett and Howard space for a free and open exchange on the new research at this blog site.