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Critiques and Reviews of Research and Publications

Latest critique (updated 27 September 2014)

Health Effects of Water Fluoridation: a Review of the Scientific Evidence
A report on behalf of the Royal Society of NZ and the Office of the Prime Minister's Chief Scinece Advisor.(August 2014)

This review does not meet the standards of robust scientific analysis. It cherry-picks studies that support fluoridation, as has become the norm for fluoridationists. We consider it unscientific and intellectually dishonest.

Documents obtained under the Official Information Act reveal that this is NOT a review of the scientific evidence, but is the product of the views of the pro-fluoridation panel members.

The report was prepared in secret, to meet a political timeframe.

We sent this report out for review by five independent international experts. The first of three critiques can be viewed here (opens in a new window).

The fifth reviewer is finalizing a more detailed review of the neurotoxicity question, which is an area of current focus for him. That review will be added in due course.

A third review is currently in draft, and will be added once finalized.

Dr Beck has authorized publication of his following comment:

"This report is a clear example of cherry picking, where only select studies that support the 'safe and effective' viewpoint were cited. It is far from a REALLY critical review of the literature. It is NOT a meta analysis."

We will post more detail about this ignominious 'review' once we have obtained the further official information we have requested.

Investing in professional advocacy: a case study of a successful fluoridation campaign in rural New South Wales, Australia. Sivaneswaran & Chong (2011). Community Dental Health, 28(3), pp 243-247.

This case study describes strategies employed in the implementation of fluoridation in two rural towns in New South Wales, Australia. Water fluoridation had been hindered by organised and vocal opposition.
These included:

  • 100% subsidy on capital costs
  • building relationships with the local media
  • public forums
  • wide dissemination of fluoridation information kits
  • use of contemporary local data that highlighted dental health disparity (presumably ignoring the difference in rural-urban socio-economic status that is the true cause of the disparity)
  • use endorsements by numerous national and international scientific and health organizations (instead of scientific evidence)
  • community consultation conducted by an independent research organisation on randomly selected households

These tactics are amongst those used since the 1940s. It seems unlikely they will change significantly.

Scientific Research

Association of vascular fluoride uptake with vascular calcification and coronary artery disease
Li, Yuxin; Berenji, Gholam R.; Shaba, Wisam F.; Tafti, Bashir; Yevdayev, Ella; Dadparvar, Simin
Nuclear Medicine Communications: January 2012, Volume 33, Issue 1; p 14-20

The purpose of this study was to assess fluoride uptake of vascular calcification in various major arteries, including coronary arteries, to determine whether fluoride positron emission could be used as a diagnostic tool.


"There was significant correlation between history of cardiovascular events and presence of fluoride uptake in coronary arteries. The coronary fluoride uptake value in patients with cardiovascular events was significantly higher than in patients without cardiovascular events."

"Conclusion: sodium [18F]fluoride PET/CT might be useful in the evaluation of the atherosclerotic process in major arteries, including coronary arteries. An increased fluoride uptake in coronary arteries may be associated with an increased cardiovascular risk."

The research appears well conducted, and confirms the findings of a large and wide-ranging body of research showing a link between heart disease and fluoride exposure at levels experienced in fluoridated communities.

Effects of Fluoride on the Central Nervous System
Valdez-Jiménez et al, 2010

This is a literature review, not a study in the sense of research. Such a review cannot prove or disprove neurotoxic harm from fluoride.

The review is helpful in canvassing literature on fluoride’s neurotoxicity. The review’s focus is on water fluoride levels higher than that used in water fluoridation. However the issue with fluoride toxicity is not the level in water but the total daily intake. Levels at which fluoride neurotoxicity is shown by the research canvassed in this review are reached by some members of communities fluoridated at 0.7 to 1 ppm. The studies do not address the proportion of the population with heightened sensitivity to fluoride toxicity.

The review identifies the following research findings:

  • "Various studies, both clinical and experimental, have reported that Fluoride causes alterations on the morphology and biochemistry brain, affecting neurological development of individuals and, therefore, functions related to cognitive processes, such as learning and memory. "
  • "Fluoride is capable of crossing the blood-brain barrier, which may cause biochemical and functional changes in the nervous system during pregnancy. Since the Fluoride accumulates in brain tissue before birth it has been reported that exposure of the embryo to Fluoride during pregnancy is associated with impaired learning."
  • Research results suggest that the accumulation of Fluoride in the tissue can disrupt brain neurotransmitters synthesis and nerve cell receptors, have a specific effect on protein synthesis in the brain, leading degenerative changes in neurons and changes in the cerebellar cortex. These changes indicate that Fluoride can slow growth and cell division in the cortex, and that the smaller number of mitochondria, microtubules and synaptic vesicles in the terminal may decrease efficacy between the neural connections, produce abnormal operation, and influence synaptic development during postnatal life.

The study recommends that people in communities with more than 0.7ppm fluoride in the water avoid all other sources of fluoride, including toothpaste. Even if all New Zealand adopted a maximum of 0.7ppm, this would allow ZERO margin of safety. Current official standards for "safe" fluoride exposure use a zero margin of safety on the (false) claim that dental fluorosis is only cosmetic. That argument cannot apply in the case of neurotoxicity, hence the usual safety margin of 10 would be appropriate (i.e. less than 0.1ppm).

Finally, this is not systematic review, hence the quality of research canvassed is not assessed. However, the research has been published in peer-reviewed journals of international standing, mostly since 2002, and all since 1992. Today's methodology is generally more sound than that of older studies.

Chinese research on fluoride and IQ

The following commentary should be considered in the context of the wider research base regarding water fluoridation. The York Review in 2000 rejected over 90% of studies, whether supporting fluoridation or not, as being of very poor methodology. Fluoridation promoters then complained that York was being too tough, and they should be allowed to continue to cite unsound studies, which they do.

Turning to the Chinese studies, although these are peer reviewed before publication, in general the standard of research methodology is not as high as we are used to in the West. Having research published in a Western Journal is seemingly considered more prestigious than publication in a Chinese journal.

Chris Neurath, director of American Environmental Health Studies Project, advises as follows:

"In terms of the Chinese studies of Fluoride and IQ, I've looked at all of them in detail. I helped edit the translations of a number of them. Many of them do use relatively weak epidemiological methods and do not report sufficient details to allow a decent assessment of their validity. They can therefore justifiably called $quot;weak$quot; or $quot;low quality$quot; studies. The Xiang studies are probably the strongest in that they address many of the issues. However they are still not as strong as would be desired."

Since there have been a great many studies now, almost all of which suggest Fluoride exposures not too much different than in artificial fluoridation areas may lower IQ, or have general neurotoxic effects (Mullinex 1995, Varner 1998, Guan 2004), these findings demand follow up with stronger studies, rather than being dismissed out of hand. Our Ministry of Health has a statutory duty to do so.

However, those who promote fluoridation do not seem inclined to do so; rather they seem focussed solely on criticising the Chinese studies as grounds for ignoring them. Given their continued reliance on extremely poor studies, rejected by the York Review, this seems a double standard. Either studies of this quality are acceptable or not – it does not depend on whether they support or challenge fluoridation policy. We note that even ESR adopted this double standard in its 2000 report on fluoridation.

Publications by the Ministry of Health etc.

Oral Health Survey, Ministry of Health 2010

This survey specifically excluded any scientific study on fluoridation, and states so (page 167). Claims that this Survey proves fluoridation reduces tooth decay are simply false.

The Survey briefly discusses, selectively, some studies claiming a benefit from fluoridation. In fact, some of those studies found no benefit, or conflicting results. It selectively omits studies that did not find any benefit, such as the Australian Armfield and Spencer study published in 2004.

Perhaps the only possibly valid information relevant to fluoridation is the macro-data from the Minsitry of Health showing that tooth decay has slightly INCREASED in FLUORIDATED areas and slightly DECREASED in UNFLUORIDATED areas since 2003. While the absolute values cannot be relied on, as they are not controlled for sociodemographic status or other possible factors, the trend in each group is not dependent on such control.

But overall, this report has no place in a scientific debate on fluoridation.

Publications of the National Fluoridation Information Service
- a Government-funded lobby group.

This lobby group was orignally to be named "The National Water Fluoridation Support and Coordination Service", but was re-branded" as an information service. Its contract for services makes its true purpose quite clear -to promote fluoridation.

On 15 March 2011 this lobby group funded by the Ministry of Health, and working out of Wellington Regional Public Health, circulated a document to all councillors and community board members in NZ. The group issued it under the name "National Fluoridation Information Service". The information was grossly inaccurate, and unsupported by any scientific references.
Open or download original document.

On 30 March 2011 NZFIS circulated an annotated version of this document, to ensure decision makers had accurate information.
Open or download our document.

Advisory on Delayed Tooth Eruption

The NFIS has released an "Advisory" on delayed tooth eruption.
Our full critique is available here.

This document seems more of a personal attack on Dr Connett than an objective scientific "advisory". This is hardly surprising, given NFIS’ preoccupation with countering Dr Connett’s 2011 speaking tour of NZ.
The report is filled with misinformation and mischaracterization of what Dr Connett said. Their criticisms of Dr Connett's comments on delayed eruption are essentially based on half-truths and overly strict interpretations.
The real bottom line is that very few studies have ever considered delayed eruption, just as the York Review pointed out. This NFIS critique is hardly sufficient to dismiss the concerns of the York Review.

Evidence-Based Clinical Recommendations Regarding Fluoride Intake From Reconstituted Infant Formula and Enamel
Fluorosis : A Report of the American Dental Association Council on Scientific Affairs

Joel Berg, Catherine Gerweck, Philippe P. Hujoel, Rebecca King, David M. Krol, Jayanth Kumar, Steven Levy, Howard Pollick, Gary M. Whitford, Sheila Strock, Krishna Aravamudhan, Julie Frantsve-Hawley and Daniel M. Meyer
JADA 2011;142;79-87

Recommendation: dentists should advise parents top keep using fluoridated water even when it can provide no benefit (up to age 6 months) in spite of the risk of dental flourosis, of which they should merely be "cognizant".

One systematic review (conducted by the American Dental Association itself) and two clinical studies were considered in developing the recommendation. 20 pieces of published research were excluded.

This is a piece of PR spin commissioned by the ADA, using a panel of fluoridation promoters, to be cited as “evidence” that fluoridaters can ignore the risks to bottle-fed infants. The "review’s". sole apparent purpose is to perpetuate the ADA’s fluoridation policy.

September Newsletter

We have sent the following critique and communication to the NFIS co-ordinator, Emmeline Haymes. We will advise her response when available.

This newsletter contains an article entitled "the 'F' word". This article contains serious errors of fact, and deception by commission and omission.

Request for official information
1a) Who wrote this article
1b) Who peer reviewed this article
1c) Who authorized its publication?

The article states that fluoride is a nutrient.

Request for official information
2a) On what authority does the author rely in claiming that fluoride is a nutrient.
2b) What evidence does the author hold that this "authority" is more authoritative than any authority stating that fluoride is not a nutrient

Response: the author relies on the Nutrient Reference Values for Australia and NZ 2006.
We attach our critique.

The article states that "Ingestion of fluoride reduces dental caries in both the formation and retention of teeth".
It has been accepted since 1999 that ingestion of fluoride does not have any significant benefit in reducing tooth decay. Even Dr Robin Whyman only claims that fluoridated water provides topical benefit.

Request for official information:
3a) On what peer-reviewed research published since 31 December 2000 does the author rely in claiming benefit from ingestion of fluoride.
3b) What correspondence with the US Centers for Disease Control and Prevention or the American Dental Association, dated on or after 1 January 2001, does the author possess where the relevant organization confirms its position that benefit from fluoridation is not systemic (to any significant extent) is wrong?

The article states that the Oral Health Survey 2009 found no difference in dental fluorosis rates between fluoridated and unfluoridated communities. However the Survey states that it conducted no research into fluoridation. Conversely, the only two recent pieces of published peer-reviewed research on dental fluorosis in NZ (the standard required by the Ministry of Health) both found fluorosis rates doubled in fluoridated communities compared with unfluoridated communities. NFIS’ contract with the Ministry of health requires the provision d information. The NFIS itself states that his is it practice. How do you justify citing non-peer-reviewed non-research to make a claim refuted by peer-reviewed published research – how do you claim to be providing "objective balanced information" rather than promulgating misleading, biased, propaganda?

The article also states "The survey found that children and adults living in fluoridated areas had significantly lower lifetime dental decay experience than children and adults living in non-fluoridated areas. Although only a snapshot, these findings suggest that fluoridation of community water supplies continues to provide protection against dental decay in all age groups across the population".
To be objective, you would need to state that scientifically, no conclusion whatever could be drawn from these figures, since the fluoridated areas are also, on average, the high socio-demographic areas. You would also need to state that the most recent research in NZ found “no difference in the incidence or severity of tooth decay” between fluoridated and unfluoridated communities, and one of the best pieces of research – Armfield and Spencer 2004 – found no difference from age 12. Again, how can you honestly claim to be giving "balanced, objective advice" when selectively citing non-research to make claims not supported by published peer-reviewed research?

Book Reviews

Scientific Knowledge in Controversy – the Social Dynamics of the Fluoridation debate
Brian Martin, 1991.
Access e-book for download

This is an excellent sociological study, for those wanting to understand how the fluoridation battle has been fought. It gives valuable insight to the question "If the science is as poor as opponents of fluoridation claim, why do promoters keep pushing it?"

The author takes no position on the science of the issue. If he has a personal view on fluoridation, it is not apparent from this book.

The Case Against Fluoride: How Hazardous Waste Ended Up in Our Drinking Water and the Bad Science and Powerful Politics That Keep it There
Dr. Paul Connett; Dr James Beck; Dr Spedding Micklem; 2010.
See details on the publisher's web site.

This is a very readable, easy to follow, book for the non-technical person. The authors take a new look at the science behind water fluoridation and argue that just because the dental and medical establishments endorse a public health measure doesn't mean it's safe. The scientific studies are fully referenced.

Carl Hays (a Booklist Online reviewer) has applauded the book:

"On the eve of the new millennium, the Centers for Disease Control (CDC), listed water fluoridation as one of the twentieth-century’s 10 greatest public-health achievements. Yet according to the authors of this painstakingly researched expose of fluoridation’s overall ineffectiveness and toxicity, endorsements such as these from the CDC and other health organizations are motivated more by face-saving politics than credible research.
Fluoridation advocates who have previously branded detractors as conspiracy theorists and shills for junk science will be hard pressed to debunk the hundreds of peer-reviewed studies and sound scientific reasoning presented here."