New Evidence of Harm from Fluoridation

Story at-a-glance

  • New research links public water fluoridation to significant increases in ADHD in the US and hypothyroidism in the UK
  • New study shows link between dental fluorosis and IQ damage in children. There are now over 100 animal studies and over 43 human studies proving fluoride’s neurotoxicity
  • Evidence has been uncovered showing government agencies trying to hide disproportionate harm to minority communities caused by fluoridation


This is an older article that may not reflect Dr. Mercola’s current view on this topic. Use our search engine to find Dr. Mercola’s latest position on any health topic.

By Stuart Cooper
Campaign Manager, Fluoride Action Network (FAN)

Just when you thought the evidence against fluoridation couldn’t get any more damning, several new studies and reviews have been published so far in just the past five months that ought to condemn fluoridation to the history books once and for all.   

The video above features a brief overview by Dr. Paul Connett, director of the Fluoride Action Network (FAN),  about the health risks of water fluoridation you may have not been aware of.

Water Fluoridation Linked to Higher Prevalence of ADHD

A new study links water fluoridation to attention deficit hyperactivity disorder (ADHD) in the United States. The study,1 entitled: “Exposure to fluoridated water and attention deficit hyperactivity disorder prevalence among children and adolescents in the United States: an ecological association,” was published in the journal Environmental Health in February.

According to the authors:

“State prevalence of artificial water fluoridation in 1992 significantly positively predicted state prevalence of ADHD in 2003, 2007 and 2011, even after controlling for socioeconomic status.

A multivariate regression analysis showed that after socioeconomic status was controlled each 1 percent increase in artificial fluoridation prevalence in 1992 was associated with approximately 67,000 to 131,000 additional ADHD diagnoses from 2003 to 2011.

Overall state water fluoridation prevalence (not distinguishing between fluoridation types) was also significantly positively correlated with state prevalence of ADHD for all but one year examined.

Conclusions: Parents reported higher rates of medically-diagnosed ADHD in their children in states in which a greater proportion of people receive fluoridated water from public water supplies."

Elevated Hypothyroidism Rates Linked to Fluoride Consumption in the UK

Also in February, a major fluoridation study was published in the Journal of Epidemiology and Community Health--a British Medical Journal (BMJ) publication—and it’s already getting major media attention.2

The study3,4,5 is a large observational evaluation of GP practice data and fluoride levels in drinking water. It’s the first study to ever look at fluoridation and hypothyroidism in a large population, in this case, England.

It found a relatively strong and statistically significant effect, with General Practice (GP) areas being 62 percent more likely to have high rates of diagnosed hypothyroidism if their drinking water fluoride levels were above 0.7ppm compared to areas with fluoride levels below 0.3ppm.

This was after researchers had accounted for key confounders, which are other factors that influence hypothyroid rates.

An additional comparison was performed of two large metropolitan regions, one that is artificially fluoridated at a level of about 1.0 ppm (greater Birmingham area), and the other which is nearby and similar demographics but is not artificially fluoridated (greater Manchester),

The study found a 94 percent greater probability that GPs in fluoridated Birmingham would have high hypothyroidism rates compared to Manchester. For all of England, the prevalence rate of hypothyroidism was almost 10 percent greater in those GPs with higher fluoride levels compared to those with lowest levels.

The findings led to the researchers calling for a “rethink of public health policy to fluoridate the water supply,” adding “consideration needs to be given to reducing fluoride exposure, and public dental health interventions should stop [those] reliant on ingested fluoride and switch to topical fluoride-based and non-fluoride-based interventions.”

Fluoride Is an Endocrine Disruptor

According to FAN’s Science Director, Chris Neurath:

“Scientific and medical research stretching back to the 1920s has shown that fluoride can affect the thyroid. The levels of fluoride exposure known to lower thyroid function overlap with the levels of exposure known to occur in some people drinking artificially fluoridated water.

Hypothyroidism is a very common disorder in the US. It can have serious adverse health effects. Reduced thyroid function in pregnant women is linked to reduced IQ in their children.

There is accumulating evidence that fluoride, at levels within the range fluoridated populations are exposed to, is associated with lowered IQ. Fluoride's effect on thyroid function might be the mechanism by which it lowers IQ.”

The article notes that "thyroid dysfunction is a common endocrine disorder..." The first time fluoride was labeled an endocrine disrupter was in the 2006 report6 of the National Resource Council of the National Academies.

According to the National Institutes of Health,7 “Research shows that endocrine disruptors may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming.”

As far as we know, promoters pushing fluoridation have never referred to this ominous label. FAN’s study tracker8 also contains a number of previous studies showing fluoride has a detrimental effect on thyroid health.

New IQ Study Links Fluorosis to Neurotoxicity

There are over 100 animal experiments linking fluoride consumption to a decrease in IQ. Thirty-one animal experiments out of 33 that investigated animal behavior also showed learning and memory problems associated with fluoride consumption, and 43 out of 50 human studies have shown that modest levels of fluoride negatively affect IQ. The video below features Michael Connett of the Fluoride Action Network giving a presentation on the mounting evidence that fluoride reduces IQ in children.

Twenty-seven of these studies were recently reviewed by a team from Harvard School of Public Health. Twenty-six of these studies showed a decrease in IQ (an average drop of 7 points), and the average fluoride level in the water for 20 of these studies was only 3.52 ppm, which is lower than the current safe drinking standard in the US for fluoride of 4.0ppm. 

Knowing this, it should come as no surprise that a new study on fluoride’s impact on IQ further proves the neurotoxicity of the drinking water additive. This new pilot study9 in China looked at lifetime exposure to fluoride and cognitive functions in Chinese children. It was carried out at fluoride levels that overlap levels used in US fluoridation programs. They didn’t measure IQ specifically in this study, but reported the results of a very simple test: the child’s ability to repeat a sequence of numbers both forwards and backwards.

Total Video Length: 26:25

Even children with very mild dental fluorosis performed less well on this specific mental development test, compared to children without fluorosis. One of the experts involved in this study was Dr. David Bellenger who is world famous for his studies on lead’s neurotoxicity. Another co-author was Dr. Philippe Grandjean, and in an editorial on his website Chemical Brain Drain10 he used this study to counteract the claim from proponents that the IQ findings were not relevant to the fluoride levels used in water fluoridation. Grandjean writes:

“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… Prevention of chemical brain drain should be considered at least as important as protection against caries.”

HHS Admits Overexposing Americans to Fluoride

In April, the U.S. Department of Health & Human Services (HHS) admitted that the fluoride levels, which they promoted and encouraged as safe, has damaged children’s teeth.11,12,13 Because of the major increase in dental fluorosis (white spotted, yellow, brown and/or pitted teeth) on the teeth of 41 percent of teenagers,14 HHS says that water fluoride levels should be lowered to 0.7 mg/L (formerly most communities used 1 mg/L while the guideline was 0.7 – 1.2 mg/L) and in 10 years they’ll check children’s teeth to see if they were right about this new level.

In January 2011 when the HSS first announced this recommendation, the US Environmental Protection Agency’s Office of Water released documents to substantiate the safety of continuing water fluoridation. However, the EPA has not yet responded to the many substantive comments they received (eg, FAN’s submissions: Dose-Response Analysis for Non-Cancer Effects and Exposure and Relative Source Contribution Analysis).

So while HSS has finalized the guideline for the level of fluoride in fluoridation schemes, the safety of the issue has not yet been addressed. The HSS response to these concerns was to whitewash them. HHS ignored hundreds of animal studies that reported adverse health effects from fluoride and the 43 studies linking fluoride to children’s lowered IQ. When fluoridation began, officials had no idea that fluoride could affect cognitive functions. 

Nor did HHS comment on two well-publicized studies released this year linking fluoridation with ADHD15 (attention deficit hyperactivity disorder) and underactive thyroid. HSS did not address the fact that infants who receive formula made with fluoridated water at the new guideline level will receive 175 times more fluoride than breast-fed infants. David Kennedy DDS, a member of FAN’s Board of Directors, noted: “The HHS continues its long term support for a policy that grossly overdoses bottle-fed infants and others in our communities with fluoride.”

HSS also stated in its press release that a report16 on the toxicology of fluoride by the National Research Council of the National Academies “found no evidence substantial enough to support effects other than severe dental fluorosis at these levels.” What HSS failed to state is that the NRC report of 2006 stated for the first time that fluoride is an “endocrine disruptor,”17 which means it has the potential to wreak havoc with the biology and fate of humans. This is far more significant than severe dental fluorosis. Yet severe dental fluorosis is the only endpoint of concern that HSS considers as an adverse effect of fluoride exposure.

According to the HSS, the good news is that “the new recommendation will lead to a reduction of approximately 25 percent (range: 12 percent–42 percent) in fluoride intake from drinking water alone and a reduction of approximately 14 percent (range: 5 percent–29 percent) in total fluoride intake.” HSS says at least 96 percent of the 19,300 comments they received were opposed to adding fluoride to drinking water.

They mentioned Fluoride Action Network indirectly when they said that 18,500 comments came from “an organization opposing community water fluoridation.” None of the concerns that Fluoride Action Network submitted18 to HSS in 2011 were adequately responded to in HSS documents released on . These concerns included:

  1. Using the water supply to mass medicate the population is unethical.
  2. The benefit and safety of ingested fluoride has never been proved by accepted medical standards.
  3. Any benefits of fluoride are primarily topical, not systemic.
  4. Americans will still be over-exposed to fluoride at 0.7 ppm.
  5. Infants will not be protected.
  6. African-American children and low-income children will not be protected.
  7. HHS has failed to consider fluoride as an endocrine disruptor.
  8. HHS has failed to consider or investigate current rates of skeletal fluorosis in the US.

Fluoridegate: New Evidence of Government Cover-up

Using the Freedom of Information Act, Daniel Stockin of the Lilie Center in Georgia  obtained all the un-redacted correspondence19 among  individuals at the CDC, ADA, and Pew involved in the attempt in May-June of 2011 to “put the lid on” concerns from Civil Rights leaders in Atlanta (former UN Ambassador Andrew Young; the Rev Durley and the niece and daughter of Martin Luther King, Jr.) about the disproportionate harm fluoridation is causing Black and Hispanic communities in the US, and the failure of the CDC to warn these communities of their extra vulnerabilities to fluoride (“FluorideGate”).20,21, 22,23,24

These statements from Civil Rights leaders were of huge concern to fluoridation promoters. According to Dr. Leon Stanislav (who was sent by the ADA to the meeting discussed below): “This is becoming a very large picture with a movement through the black ministries and, possibly, even as high as the administration.” (p.260)

Having read through the 320 pages of documentation25 provided by FOIA, it is clear that much of the information has been redacted—80 pages were blanked out, and another 45 pages were partially blanked out. It is puzzling that so much of the discussion on this public health practice is deemed so confidential it has to be kept hidden from the public. Usually, there are very serious reasons (e.g. national security) why FOIA pages are redacted. However, in this case national security would not apply. So when it comes to the defense of a public health practice the redaction of so much material would seem to fly in the face of the spirit of the Freedom of Information Act.

The Morehouse College Meeting

The key event at the heart of the “fluoridation fortress (CDC, ADA, Pew)” response to the Civil Rights’ leaders was a meeting held at Morehouse College in Atlanta on June 1, 2011. The meeting was organized behind the scenes by the PEW Charitable Trusts, but they had no representative at the meeting (p.259).

Involved in the discussions before the meeting was Dr. William Maas, former Oral Health Director of the CDC who in 2011 was working for Pew as a consultant.  In one of his emails (dated May 6 to Dr. William Bailey the current Oral Health Director at the CDC) he is clearly worried about the ramifications of the number of studies indicating fluoride damages the brains of both animal and humans.

He writes:

"Bill, you may recall that I suggested some time ago, perhaps even before you were CDO, that we ought to find someone who is 'the Gary Whitford of brain change or IQ studies.' If my recollection is correct, some of the very first studies associating fluoride with IQ were refuted by a review of David Locker. Of course his death has ended that source of ongoing rebuttal. I thought it best that we find out the types of people that other divisions of the CDC would use to answer questions about whether substances cause brain alteration.

Of course our biases may be entirely different that [sic] other divisions. They may be looking for the slightest evidence that something in the environment is bad for brains, whereas we are only interested in compelling evidence that our favorite substance causes brain changes, and want to minimize the credibility of poorly conducted studies or well-conducted studies that are not relevant.

While I don't want to completely dismiss the possibility that fluoride in water at levels provided to the public in the US (that would be 4mg/L or less) causes brain changes, IQ changes, etc, I suspect that all of these 130 studies that were mentioned share some common flaws that someone who studies IQ and brain changes for a living would be able to identify and summarize for us, (much as we've used Gary Whitford to help us understand the flaws in studies purporting changes to kidney functions, etc.)..."

One notices with this comment a common feature in the activities of the CDC, ADA, and Pew. The emphasis is on finding ways to deny harm rather than a genuine effort to find out if harm is being caused by this practice. It is 20 years since the first animal studies on fluoride’s neurotoxicity (Mullenix et al, 1995) and subsequent IQ studies were published. Why has so little effort been put into research on this issue in the US and other fluoridated countries? As Dan Stockin concludes in his media release,26 “Fluoridegate is about officials being more concerned to protect water fluoridation at all costs than protecting the health of the people they serve.”


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