For earlier articles in this series see:
Paul Connett, director of the Fluoride Action Network (FAN), admits in his Fluoride Action Network (FAN) Bulletin from March 24, 2020: “You only have to read four studies…” that “Many of the earlier studies were in places with elevated natural fluoride levels.” Yes – they are overwhelmingly from areas of endemic fluorosis, mainly in China, where health problems are very common and obvious. They have no relevance to community water fluoridation (CWF) – but this did not stop Connett, FAN and the whole anti-fluoride movement using them in their propaganda opposing a safe, effective and economic health policy known to reduce child tooth decay.
But he now claims “You only have to read four studies…” to come to the conclusion that community water fluoridation (CWF) is bad for your health. As I said in the first article in this series that is simply bad science. One should not ignore all the other relevant studies – and anyway, these four studies do not say what Connett claims.
Oh, but what about Santa-marina et al (2019)
In this article, I discuss a study Connett purposely ignored. The whole anti-fluoride activist movement has avoided discussing this study. It’s citation is:
Santa-Marina, L., Jimenez-Zabala, A., Molinuevo, A., Lopez-Espinosa, M., Villanueva, C., Riano, I., … Ibarluzea, J. (2019). Fluorinated water consumption in pregnancy and neuropsychological development of children at 14 months and 4 years of age. Environmental Epidemiology, 3.
Of course they ignore it, pretending it doesn’t even exist because it doesn’t confirm their bias!
As Table 7 below shows, Santa-marina et al (2019) reported statistically significant POSITIVE relationships of child cognitive measures with drinking water-fluoride. The red triangle indicates the relationship was statistically significant and the bars represent the 95% confidence interval
I have already commented on the likelihood that this study suffers from many of the same weaknesses as the other studies discussed in this series – the four studies Paul Connett is actively promoting. The large confidence intervals indicate that the reported relationships will explain only a small percentage of the variance in cognitive measurements.
But, the point is this is another study that has as much right to be considered as the ones used by Connett. And there are others. Connett and other anti-fluoride campaigners purposely exclude studies they cannot use to support their anti-fluoride bias. Studies like those of Broadbent et al (2015), Aggeborn & Öhman (2016), Barberio et al (2017) and Perrott (2018).
The important thing is that the results reported in all the four studies promoted by Connett are contradictory. They lack consistency. Different measures of cognitive ability and fluoride exposure are required to find significant relationships. All the reported associations are weak and there are many statically non-significant associations Connett, and the authors themselves, just don’t discuss.
The critical and intelligent reader needs to take these factors into account instead of cherry-picking results which fit their agenda.
One does not make changes to health policy based on such weak evidence.
Taking in each other’s laundry
Tomorrow I will discuss the links between the four papers Connett is promoting to show that they are not independent. These authors also tend to act as journal reviewers for each other’s papers. To a large extent, the researchers involved are taking in each other’s laundry. See Anti-fluoridation propaganda now relies on only four studies. 6: Incestuous relationship of these studies.
- The anti-fluoride brigade won’t be erecting billboards about this study
- What are the recent fluoride-IQ studies really saying about community water fluoridation?
- Anti-fluoridationists put faith in new “strong” studies to provide evidence missing in draft NTP review