Known About Fluoride
Upper Intake Level
Interferes with Brain
Pharmacy or Faucet?
Bogus Sales Pitch
FDA Fluoride Drugs
Why You Should Not Believe the Fluoridation Sales Pitch
Fluoridation promoters are obsessed with decayed teeth. They rarely mention healthy teeth, however, a major Australian survey did report the total number of teeth allowing us to deconstruct the ad nauseam claim that fluoridated water significantly reduces tooth decay.
Armfield JM, Slade GD, Spencer AJ. Water fluoridation and children's dental health. The Child Dental Health Survey, Australia 2002.
DMFT = decayed, missing, and filled teeth (i.e., past and present decay)
Fluoridated 12-year-olds averaged about 1.0 decayed teeth, and unfluoridated kids 1.5 a difference of 0.5 teeth. The authors said this was a relative difference of 50.6% more decay (p. 27). True, but relative percentages are irrelevant without the "absolute" numbers, which the total number of teeth can provide.
Out of a total of about 24 teeth, unfluoridated 12-year-olds averaged 22.5 healthy teeth and fluoridated kids averaged 23. That's only about 2% more healthy teeth a far cry from the 50% sales pitch.
Deconstructing US fluoridation claims:
The US government's biggest and best fluoridation study claimed:
Fluoridation Reduces Tooth Decay by 18%
Recent trends in dental caries in U.S. children
and the effect of water fluoridation
This 1990 study compared the number of unhealthy permanent teeth of 39,000 children aged 5-17 years. This was measured by DMFS: the number of decayed, missing, and filled tooth surfaces (i.e., past and present decay). Results by ages are reported in Table 6:
Nonfluoridated kids averaged 3.39
Fluoridated kids averaged 2.79
A difference of 0.6 decayed surfaces
The government dentists divided 0.6 by 3.39 to claim: "Children who had always been exposed to community water fluoridation had mean DMFS scores about 18% lower than those who had never lived in fluoridated communities."
Again, 18% is a misleading "relative" difference as becomes obvious for 5-year-olds where a tiny difference of seven-100th of a tooth surface = 70% less tooth decay!
Like most dental studies, unhealthy teeth are the focus on this study, as its title indicates: "Recent trends in dental caries..." The total number of tooth surfaces was not stated, but a tooth has 4 or 5 surfaces.
In the above Australian survey, 12-year-olds averaged 24 teeth so they have at least 100 tooth surfaces. When focusing on healthy teeth, the absolute numbers tell the accurate story:
Nonfluoridated 12-year-olds had approx. 97.0 healthy tooth surfaces.
Fluoridated kids had about 97.5 healthy tooth surfaces.
Using these absolute numbers, half of one tooth surface is a 1% difference in the number of healthy teeth of fluoridated vs unfluoridated 12-year-olds.
The Mouthwash Effect
Although less than the margin of error, a 1% difference could reflect
the topical effect of fluoride while fluoridated water is in the mouth.
FDA Confirms Ineffectiveness of Fluoridated Water
After reviewing the best available evidence,
FDA would only allow this very weak
Health Claim for Fluoridated Water:
"Drinking fluoridated water may reduce the risk of tooth decay."
OMG! The chance of getting a cavity might be reduced.
The same can be said for drinking clean water.
Consuming fluoridated water, however, certainly does increase the risk of dental fluorosis, visible evidence of an individual's susceptibility to fluoride's adverse systemic effects. The British Fluoridation Society says the prevalence of dental fluorosis is 15% in nonfluoridated areas and 48% in fluoridated areas.
Another Australian Study Revels Statistical Spin
In a 2010 study, Community effectiveness of public water fluoridation in reducing children's dental disease, Jason Armfield (one of the 3 authors of the above 2002 Australian survey) reported these results:
In the permanent teeth of 8- to 15-year-old children residing in areas with negligible fluoride and those residing in optimally fluoridated areas, "the absolute magnitude of difference" was 0.25 decayed teeth (0.79 vs 1.04), "and this represented a relative difference of 31.6%."
But in his abstract which is all that usually gets reported and promoted to the public Armfield only stated the misleading relative difference:
"Permanent caries experience was... 31.6% higher... in low-fluoride areas compared with optimally fluoridated areas."
To get that 31.6% benefit, Armfield divided 0.25 by 0.79. He could have divided 0.25 by 1.04 to claim: Permanent caries experience was 24% lower in optimally fluoridated areas compared with low-fluoride areas.
For 12-year-olds (Table 2), Armfield reported it as a "51 percent difference."
Again: when focusing on healthy teeth,
the absolute numbers tell the true story:
For 12-year-olds, low fluoridated kids averaged 1.31 decayed teeth. High fluoridated kids averaged 0.87 decayed teeth, an absolute difference of 0.44 teeth. Out of 24 teeth, that is a 2% difference in healthy teeth.
Despite this, Armfield's begins his abstract: "Water fluoridation is one of the most effective public health programs of the past century. However, efforts to extend water fluoridation into currently non-fluoridated areas are often thwarted. Despite considerable evidence regarding the effectiveness of water fluoridation..."
"The announced opinions and published papers favoring mechanical
fluoridation of public drinking water are especially rich in fallacies...
and afforded great amusement." Mathematics professor (1980)
Innumeracy in Medicine
The use of misleading statistics to promote drugs is a widespread form of fraudulence very much exploited by Pharma. "Innumeracy is rampant in medicine," says Ira L. Goodman, MD. For example:
"In a popular Lipitor study, the 'benefit' of a statin over 4 years was reported as 28% reduction in events. This number is clinically irrelevant without the absolute numbers, which showed only a 3% difference in events."
Even in a highly educated, extremely intelligent, and motivated group such as physicians, innumeracy in medicine is common, Goodman says. "How many have the time to read past the sales pitch (i.e., the abstract)?"
Deconstruct recent example:
Stopping statins increases stroke by 42%!
Sad but Amusing
It's amazing how otherwise-intelligent people fall for the fluoridation sales pitch, even though they claim to know better:
"Whenever you see a percent change in risk, the first question you need to ask is whether or not this is an absolute or relative risk." Steven Novella, head of Science-Based Medicine
Novella ignores his own advice in Antifluoridation Bad Science, when he says people "distort the evidence" if they argue that fluoridation is not effective.
Then he links to "the policy statement on fluoridation by the Institute for Science in Medicine" (that he is Board Chairman of):
"Scientific studies have established that CWF [Community water fluoridation] lowers the rate of tooth decay by 20-40% in children..."
Reference 9 is Brunelle & Carlos (1990). As discussed above, that huge study showed an insignificant 1% difference in undecayed tooth surfaces from fluoridation.
Don't Be Takin' Fluoride!
The next time you're tempted to buy
the bogus fluoridation sales pitch,
just say to yourself:
(like Jerry Seinfeld says "Newman!")
Fun with Numbers