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Jeff Sutherland

Twice the Energy with Half the Stress

Pseudoscience: ADA Spokesperson Makes False Statements About NRC Study of Thyroid

Politics trumps science anytime money is involved. As new scientific journal articles continue to roll out on brain damage, tooth damage, thyroid damage, and other negative side effects of a toxic carcinogen like flouride, the so-called scientific proponents of flouride distort or ignore the findings. And our so-called health sites like WebMD promote the disinformation. Fortunately, some of the scientists doing the real studies are starting to complain about the nonsense inflicted on the American public.

See flouridealert.org for more complete documentation:

A spokesperson for the American Dental Association made an inaccurate statement in the media recently while criticizing the latest study showing hypothyroidism’s link to fluoridation.   
Dr. Edmond Hewlett, ADA spokesman and a professor at the UCLA School of Dentistry has been quoted by numerous publications discounting the study, stating that other studies have not uncovered a link between fluoridated water and thyroid problems, saying: 

“the 2006 report by the U.S. National Research Council (NRC) found no adverse effects on the thyroid even at levels more than four times greater than that used in fluoridation.”

The quote appeared in a number of articles including those by the Chicago Tribune,HealthDay, and WebMD.  It’s an absolutely false statement, as FAN’s NRC Thyroid webpage makes very clear.  What isn’t clear is whether Dr. Hewlett intentionally lied when making the statement, or if he just lacked the knowledge to make an accurate statement on the matter. 

Kathleen Thiessen, Ph.D., who was one of the authors of the 2006 NRC report on fluoride, responded to the inaccurate statement with the following letter to the author of the HealthDay article that quoted Dr. Hewlett:

Regarding a recent HealthDay article by Alan Mozes, which has been used by the Chicago Tribune, WebMD, and probably others: 

The article on fluoride and underactive thyroid, reporting on a recent publication by Stephen Peckham et al., quotes a representative of the American Dental Association as saying that “the 2006 report by the U.S. National Research Council found no adverse effects on the thyroid even at levels more than four times greater than that used in fluoridation.”  This statement by the ADA spokesman is demonstrably inaccurate.  

From the NRC report 
pp. 262-263: Fluoride exposure in humans is associated with elevated TSH concentrations, increased goiter prevalence, and altered T4 and T3 concentrations. . .  In humans, effects on thyroid function were associated with fluoride exposures of 0.05-0.13 mg/kg/day when iodine intake was adequate and 0.01-0.03 mg/kg/day when iodine intake was inadequate.  
p. 260: The major endocrine effects of fluoride exposures reported in humans include elevated TSH with altered concentrations of T3 and T4. . . .  These effects are summarized in Tables 8-1 and 8-2, together with the approximate intakes or physiological fluoride concentrations that have been typically associated with them thus far.  Table 8-2 shows that several of the effects are associated with average or typical fluoride intakes of 0.05-0.1 mg/kg/day (0.03 with iodine deficiency). . . . A comparison with Chapter 2 (Tables 2-13, 2-14, and 2-15) will show that the 0.03-0.1 mg/kg/day range will be reached by persons with average exposures at fluoride concentrations of 1-4 mg/L in drinking water, especially the children.  The highest intakes (>0.1 mg/kg/d) will be reached by some individuals with high water intakes at 1 mg/L. . . . 
also
p. 266:  Fluoride is therefore an endocrine disruptor.
p. 234:  Thus, several lines of information indicate an effect of fluoride exposure on thyroid function.
(Note:  I was one of the authors of the 2006 NRC report.  The NRC report is available at http://www.nap.edu/catalog/11571/fluoride-in-drinking-water-a-scientific-review-of-epas-standards)
Kathleen Thiessen, Ph.D.

Oak Ridge Center for Risk Analysis, Inc. 

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Harvard IQ Researchers Respond to Pro-Fluoridation Criticism
The authors of the 2012 Harvard Meta-analysis that highlighted fluoride’s role as a developmental neurotoxin, Philippe Grandjean, MD, PhD, and Anna Choi, ScD, have written a letter responding to pro-fluoridation criticism of their work by Dr. Jonathan Broadbent.  Broadbent’s counter-study and Grandjean’s letter in response were both published in the American Journal of Public Health.  In his response Grandjean states,
“We are therefore concerned that the safety of elevated fluoride exposure is being exaggerated in ways similar to those employed by vested interests to misconstrue the scientific evidence of other neurotoxicants, such as lead, mercury, and certain pesticides.  Firm dismissal of fluoride as a potential neurotoxic hazard would seem premature.”
This isn’t the first time Grandjean has responded to pro-fluoridation efforts to downplay the impact fluoride has on IQ.  In December, he challenged the spin being used by fluoridation promoters.  Grandjean’s commentary (Mottled fluoride debate) appears on his website (Chemical Brain Drain) and is printed in full below. Grandjean explained that for the children tested, 
“Their lifetime exposures to fluoride from drinking water covered the full range allowed in the US. Among the findings, children with fluoride-induced mottling of their teeth – even the mildest forms that appears as whitish specks on the enamel – showed lower performance on some neuropsychological tests. This observation runs contrary to popular wisdom that the enamel effects represent a cosmetic problem only and not a sign of toxicity. At least one of five American children has some degree of mottling of their teeth.”