A common technique of those arguing against fluoridation on the MSoF Facebook page is to dump large amounts of copypasta (from various sources) & tell us that if we’d only read it we’d see the rightness of their case. Or else, we get a lengthy list of references, & the same admonition. The problem is that if you pick a paper or two at random & do read them, you often find that they don’t say what’s claimed for them, or that they contain methodological errors that bring their findings into question.
For example: a study by Reddy et al (2011) is said to have found that fluoride accumulated at very high levels in rats’ brains. The researchers used 2 groups of male rats: one experimental group, one control. There were only 6 animals in each group, which is a very small sample size & means that the data could be skewed by a single abnormal result.
The control group supposedly received no fluoride, but then there was no information on fluoride levels in the tap water they drank or the rat chow they ate. This is a significant flaw & I’d have thought it should have been picked up by peer review.
The experimental rats apparently received 20ppm fluoride by nasogastric tube for 2 months. Actually, it’s not actually clear what dose they received: the abstract says 20ppm NaF, but the methods section says “20ppm concentration of fluoride”. These are 2 different things & again, peer review should have picked this up & required clarification. Either way the dose is about an order of magnitude higher than you’d find in fluoridated municipal water in New Zealand, which means that the paper didn’t support the commenter’s assertions of the harm done by fluoridation. Also, after those 2 months the researchers recorded 864 mg/kg F- in the rats’ brains: given that a large proportion of fluoride is normally excreted, and some of the rest fixed in apatites in bone, this figure looks extremely high & should surely have been questioned by the referees.
And in addition, both groups of rats lost a great deal of weight during the course of the study. While the average body weight of the animals was 180g (+/-20g), after 2 months the control animals weighed on average 111g, while the experimental group was down to 93g (both +/- 2g). This strongly suggests they were either ill, or not receiving adequate food; furthermore, starvation can cause inflammatory changes to tissues & so could itself explain the changes the researchers observed in the rats’ nervous systems.
Do people read these papers before they cite them?
Sources:
Reddy, P.Y., Reddy, K.P., Kumar, K.P. (2011) Neurodegenerative changes in different regions of brain, spinal cord and sciatic nerve of rats treated with sodium fluoride. J.Med.Allied Sci 1(1): 30-35
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