Paul Connett “updates” NZ MPs about fluoride?

Data from Bashash et al., (2017). Despite a statistically significant relationship of child IQ with mothers prenatal urinary fluoride, this explains only about 3% of the huge scatter in the data.

I haven’t followed the latest speaking tour of Paul Connett – organised by the local Fluoride Free NZ organisation. But I watched a TV interview with him this morning and came away thinking he is skating on very thin ice – scientifically. He has put all his eggs in one basket – promoting a Mexican study as the be-all and end-all of scientific research which should lead to the immediate ceasing of community water fluoridation.

Paul is a leader of the anti-fluoride activist group the Fluoride Action Network and appears to love visiting New Zealand during our summer (and his winter). Local campaigners seem to idolise him – and rely heavily on him as a self-declared  “world expert on fluoridation.” But this idol has feet of clay (don’t they all?).

In fact, Paul has no original research on fluoride and is simply presenting a biased picture of the scientific literature on the subject., He relies heavily on his academic status and qualifications to give his biased views respectability.

But back to the Mexican study. Paul is referring to this paper:

Bashash, M., Thomas, D., Hu, H., Martinez-mier, E. A., Sanchez, B. N., Basu, N., … Hernández-avila, M. (2016). Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6 – 12 Years of Age in Mexico.Environmental Health Perspectives, 1, 1–12.

I have written about this study in some detail in my articles:

Here I will simply return to the poor explanatory power of fluoride for the children’s IQ measured in the study.

The graph above is a plot of the data from the paper – child IQ compared with the pre-natal urinary fluoride levels of the mothers.

Now, Paul describes this study as “rigorous” and relies heavily on it. But despite a statistically significant relationship, the huge scatter in the data really stands out.

In fact, this relationship explains only about 3% of this scatter! It probably only appears because the researchers did not include any proper risk-modifying factors in their regression analysis.

Well, Paul is making a big thing of speaking to New Zealand MPs tonight to “update” them on this latest research. Rather smug because it implies the research is his – when it isn’t.

But this research does not “prove” what Connett implies. It is not as rigorous as he claims. And it is certainly not an argument to stop community water fluoridation in New Zealand.

Note: Paul Connett and I had a scientific exchange on the fluoridation issue four years ago. Interested readers can download the full text from Researchgate –  The fluoride debate.

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13 responses to “Paul Connett “updates” NZ MPs about fluoride?

  1. Just the latest of Connett’s delusionary “end all” for fluoridation. He really should find a toilet, quickly. He’s brimming over with BS. His naive opinion notwithstanding, let’s see what one of the primary researchers of the Bashash study has to say:

    In a September, 2017 email to Dr. Johnny Johnson, Jr, Dr. Angeles Mier Martinez, one of the lead researchers in the recent Bashash, et al. Mexican study, relayed:

    1. “As an individual, I am happy to go on the record to say that I continue to support water fluoridation”

    2. “If I were pregnant today I would consume fluoridated water, and that if I lived in Mexico I would limit my salt intake.”

    3. “I am involved in this research because I am committed to contribute to the science to ensure fluoridation is safe for all.”

    E. Angeles Martinez Mier, DDS, MSD, PhD
    Cariology, Operative Dentistry and Dental Public Health
    Indiana University School of Dentistry
    415 Lansing Street
    Indianapolis IN 46202

    Steven D. Slott, DDS


  2. Another paper that has been grabbed by the anti fluoride lot with both hands and touted as the best reason since the invention of the wheel, to stop Community Water Fluoridation.
    Following the Grandjean paper that was supposed to list CWF as a neurotoxin, that didnt, Followed shortly afterwards by the I.Q claim done by Grandjean again, that was done in countries with high fluoride levels and has no impact on N.Z or USA levels. But lets not let the facts get in the way of a good scaremonger. Connett will dine out on this for as long as the next shady research, meets their agenda


  3. Steve Slott quote a Bashash collaborator: “If I were pregnant today I would consume fluoridated water, and that if I lived in Mexico I would limit my salt intake.”
    Why does he attach the word “fluoridated” to water but not say, “I would limit my fluoridated salt intake.”? Otherwise it gives the casual reader the impression salt is to blame, not fluoridation of water, when actually it is fluoridation of salt being suspected.

    Need to go through various calculations.

    Ken earlier pointed out in relation to the Malin and Till study altitude to be possibly more related to ADHD than fluoridation. Also have to take into account that water boils at a lower temperature with increasing altitude so food may be less cooked, ie more preserving of some vitamins and also giving more chewing of vegetables possibly affecting teeth. And Mexico has varying altitudes. It is also complicated by high pollution in the low altitude valleys.

    You guys in the main have two-valued thinking: you can only contemplate a pro- or anti-fluoridation approach, not someone like myself who is trying to learn. I am a bit slow but trying to get into funnel plots &c to detect publication bias.


  4. Brian – your self-declaration of wishing to learn rings false. You display all the characteristics of two-valued thinking. Simply wanting to accept every anti-fluoride argument and raise confusion about anything that doesn’t support your bais.

    Can you not see it is completely pointless to ask here “Why does he attach the word “fluoridated” to water . . .” You should be directing that question of the author making the statement. Instead, you criticise them being their back.

    And you completely misrepresent me. I have never ” pointed out in relation to the Malin and Till study altitude to be possibly more related to ADHD than fluoridation.” I have simply done the multiple regression with available data and confirmed the previously reported significant relationship between ADHD prevalence and altitude – and confirmed there is no relationship of ADHD with fluoridation incidence. There was no talk form me of a degree of relatedness

    Now, if you want to advance specific mechanisms underlying the relationship with altitude then you are welcome to. But pure speculation is completely useless. Find some data and test it.

    Hiding behind speculation to avoid the exposed falseness of the claimed relationship with fluoridation is simply avoidance. Your speculations have no worth. Data and facts are what is required.


  5. Ken that author won’t have the resources to read every email. It’s better if a group like this is a vehicle for discussion then the outcome can perhaps be used by one of us in a letter. Steve has pointed out how Angeles affirmed to the person who is actually the President of the American Fluoridation Society: “I am involved in this research because I am committed to contribute to the science to ensure fluoridation is safe for all.” In other words starting out with a bias. Not good science!!


  6. Ken I brought some speculation to the discussion for people to follow on if they wish where I might not have time. I add a point that Mexico is interesting since if fluoride comes through salt there will be less chance of variation in fluoride intake being related to altitude, since smaller higher altitude populations would be less likely to have fluoridated supplies.
    You seem to have accepted my funnel plot comment, or at least not commented.


  7. Don’t be silly, Brian. Authors often receive emails about their papers and respond to them. The comment to the President of the AFS is simply an example.

    You are not commenting in a group – you are commenting on a blog. The author will not see your comment and nobody else is interested in it.

    Please don’t flatter yourself.


  8. I do not see any motivation to “follow” your speculations. Hell, you claim you have not got the time. All you are saying is your speculations are worthless – and I agree.

    No, I do not accept any of your speculations. As I keep repeating, data, evidence and logic will interest me – unsupported speculations don’t.


  9. Ken, making hypotheses out of data runs the risk of building a hypothesis to confirm the data you have. Then something at p<0.05 can be fabricated.
    Supposed to form a hypothesis first then get the data to test it.


  10. What had the AFS president written to the article author to elicit that reply?
    That reply which said the author, though a bit embarassed by the outcome, sufficiently to warn pregnant mums off fluoridated salt, claims she is on the party line of pro-fluoridation.


  11. Brian, you cannot form a hypothesis unless you start with a basis. Speculation is not a basis. It can be nothing more than fantasy – thus bias.

    Of course, for the ideologically motivated speculation has lots of advantages because one does not have to concern oneself with facts and can pretend to be sciency.


  12. Ken sometimes a “basis” might be like, “now we’ve started on this road and invested a lot of time on it we have to stick to it,” instead of going back to the turn off point for a different direction attempt.

    OK every direction of signpost points to the antipodes, but some of the directions may follow very protracted paths.

    So go back to the turn off and look for hints.

    I had this recently. The water pressure was low at the end of the garden. I just thought of old pipe blocking. I had noticed some plants growing well a few meters from the entry point of the water on to the property, but it wasn’t till I was puzzled by a path nearby the entry point looking damp for too long after rain that I decided to investigate and found a leak which had been lowering the pressure.

    So data comes in various forms and offers a basis if we are awake. Not just digitised data if that be your requirement for something not to be speculation.


  13. Pingback: Paul Connett’s misrepresentation of maternal F exposure study debunked – The Science Page

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