Understanding the Scientific Consensus that Community Water Fluoridation is a Safe and Effective Public Health Measure

Because the scientific evidence –– as evaluated by relevant experts worldwide –– overwhelmingly supports fluoridation, the World Health Organization and over 100 other major science and health organizations worldwide (and their hundreds of thousands of members) continue to publicly support fluoridation as a safe and effective public health measure to reduce dental decay –– and NO major science/health organizations support the opinions of fluoridation opponents. In fact, fluoridation opposition only comes from: a very small minority of those with relevant science/health training/experience, a handful of alternative 'health' organizations like the IAOMT, alternative-health marketing proponents like Joseph Mercola, vocal activist groups like FAN and the CHD (with an anti-vax agenda) and a number of conspiracy theory proponents like Alex Jones [INFOWARS], David Icke [Son of the Godhead] and Mike Adams [Natural News]

Fluoridation opponents (FOs) and other anti-science activists frequently state that there is no consensus among relevant scientists and health professionals that community water fluoridation (CWF) is a safe and effective public health measure.  They provide references to studies they claim prove fluoridation causes a number of serious health effects or quote opinions from individual scientists or health professionals who disagree with the consensus.  They claim their selection of alleged "evidence" they believe demonstrates ineffectiveness or harm from drinking optimally fluoridated water is proof the scientific consensus does not support fluoridation. 

One of the most important characteristics of any scientific consensus is that it is provisional - always open to change if new, legitimate, relevant, reproducible evidence is presented that challenges a given consensus.  In fact, scientific knowledge can't progress unless current conclusions are challenged by those who disagree with a given consensus and are able to present strong supporting evidence.

It is critical for non-scientists trying to understand how to sort out facts from fiction in the fluoridation discussion (and in other science-based controversial issues) to understand the concept of scientific consensus.  For any complex scientific issue, whether it is related to health, geology, chemistry, physics, astronomy, electronics, climate, or any other scientific topic, there are hundreds to thousands of potentially relevant scientific studies which have been conducted over years to decades.  Those studies have been performed in an effort to understand specific aspects (the cause and effect relationships) found in the natural world

Like all human endeavors, the studies will have various limitations that can impact the significance and quality of the studies and any conclusions presented.  The scientific consensus " is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity." wikipedia  The scientific consensus is the best interpretation of all available scientific evidence at any given period of time, and it is subject to constant review and revision as new legitimate scientific evidence is discovered and presented.  The fact that no scientific consensus is fixed, and every scientific consensus can be challenged at any time, is the only reason scientists have formulated any any new theories about how the natural universe behaves.  That process of expert evaluation is the only reason any scientific conclusions (consensus, theories or laws) can be trusted as they relate to specific health issues or any other human endeavor based on natural cause and effect relationships which can be tested and understood as based on scientific processes.

It can be very difficult for non-scientists to understand the concept of a scientific consensus since there is nothing remotely like it outside of the sciences.  In all other NotScience fields of human endeavor (philosophy, arts, religion, law, ethics, etc) a consensus of opinions is determined by, and justified entirely on, personal beliefs.  There is no way to prove a belief or moral position is true in the same way scientists can demonstrate a cause and effect relationship in the natural world.  A personal opinion on whether Beethoven was a better (or worse) composer than Rachmaninoff, or whether birth control methods are moral or immoral, for example, can't be proven true or false by science.  Personal beliefs in natural, physical phenomena, however like "the earth is flat", "the earth and universe are about 6,000 years old", "ingesting fluoridated drinking water causes cancer (or other harm)", "vaccination causes more harm than good" etc. are, in fact, natural claims that can be (and have been) tested and evaluated by the scientific method. 


When any new potential scientific evidence is presented to the scientific community, the design, protocols and conclusions of the study are carefully evaluated by relevant experts for significance, validity and any potential bias.  Those studies determined to be relevant, valid and reasonably unbiased are compared with the entire body of previous evidence that supports the current scientific consensus.  An established consensus is only modified when the majority of experts determine the new evidence is of sufficient quality to consider a reevaluation of the consensus, and before any final decisions are made, the new conclusions must be replicated by additional independent studies.  This process of rigorous, continual evaluation based on multiple lines of verifiable, reproducible evidence is the only thing that keeps any given scientific consensus from the complete chaos which would result from accepting all conclusions from all sources as equally relevant and legitimate.


To date, despite alleged "evidence" presented by vocal opponents, the current scientific consensus in the topics listed above would be "the earth is not flat, but an irregularly shaped ellipsoid", "the universe is about 13.8 billion years old and the earth is much younger at about 4.5 billion years", "fluoridated drinking water has not been shown to cause cancer (or other harm)" and "the benefits of vaccination far outweigh any alleged harm".


It is very important to understand the difference between legitimate, reputable scientists and health care providers who legitimately challenge an accepted scientific consensus and anti-science activists who irresponsibly challenge an accepted consensus.  Legitimate scientists and health care providers do not morph into anti-science activists just because they disagree with a scientific consensus.


As described above, legitimate scientists work within the scientific community.  They present evidence that conflicts with a consensus and argue their case with relevant experts in the field.  If their evidence is not sufficient to change the consensus - or is not validated by other independent studies - they go back to the drawing board and try to obtain more compelling, reproducible evidence to support their beliefs - or they accept the consensus and go on to study something different.

There is also a minority of scientists (outliers) who have very strong beliefs, and a strong agenda to try and overturn a scientific consensus they disagree with.  These scientists can be found constantly challenging the effectiveness and policies of major science-based conclusions supported by the overwhelming majority of relevant experts - like the importance, safety and effectiveness of vaccines and fluoridation, the reality and consequences of climate change, even the age of the universe and the concept of evolution.  It is important to understand that these outlier scientists have been unable to provide any evidence to change the scientific consensus on vaccination, fluoridation and evolution despite decades of trying.  Often, these scientists try a bit of manipulation to try and reach a study outcome that matches their beliefs (Green reference below).  However, they usually publish their study conclusions as finding a "possible association or correlation" which does not even imply a cause and effect relationship (referenced below).  Examine any study published by fluoridation opponents (Associations reference below), and you will find every conclusions is only a "possible association or correlation" between drinking optimally fluoridated water and any harm they are trying to establish - the association or correlation is almost always very small.  That fact is precisely why the outliers have not been able to change the relevant scientific consensus and why they remain outliers.  Unfortunately, members of the public who have extremely strong beliefs and are against a science-based consensus (like vaccination, fluoridation, climate change, evolution) and are not trained and experienced scientists or health professionals will reference the outlier studies as providing conclusive proof that the studies support their beliefs that vaccines and fluoridation are harmful, there are no climate change issues of concern, and the earth is about 6.000 years old.
Correlation does not imply causation - Wikipedia

Some of the scientists or health care providers morph into Anti-Science Activists when:

  • They have extremely strong, inflexible philosophical, political, ethical &/or spiritual beliefs (or business goals) which conflict with a specific scientific consensus.

  • The evidence they claim to have in support of their beliefs is not of convincing quality, has been misrepresented &/or is not reproducible. Consequently, they are unable to convince other relevant scientists to consider changing the consensus.

  • These scientists then choose to abandon working within the scientific community to produce additional substantial, high-quality supporting evidence.

  • They choose not to work with other scientists to better explain their evidence and perhaps convince the scientific community their evidence and interpretations are valid.

  • They choose not to assist other scientists to successfully reproduce and confirm their experimental or observational results.

  • They then choose to take their beliefs and their interpretation of the evidence directly to the public in a deliberate effort to bypass the science and hijack the democratic process.

  • They adjust and present their “evidence” in a manner (often employing disingenuous, false fear-mongering tactics) that is most likely to sway public opinion and cause well-meaning individuals who don't have relevant scientific training or experience to join their cause.

  • They don't correct members of the public who further distort the available "evidence" as they originally presented it or those who even completely fabricate claims.

  • They argue to the public that their interpretation of their “evidence” is more legitimate than the interpretation of the vast majority of evidence by the overwhelming majority of scientists who they disagree with.

  • They promote the idea that mainstream scientists who disagree with their beliefs should not be trusted because they are part of some vaguely defined (and completely unproven) conspiracy.

At that point the scientists or health care providers have have abandoned the legitimate practices of science and become anti-science activists.  Unfortunately, since many members of the public hold similar, very strong beliefs about the same science-based issues, even though they don't have the training or experience to personally evaluate decades of complex scientific evidence, the anti-science activists can frequently find uncritical public support for their opinions.


Back to the discussion on CWF:  There are four significant pieces of evidence that confirm the scientific consensus that CWF is safe and effective:

  1. Major scientific reviews/studies over the past few years, described here, conclude that community water fluoridation is effective and/or safe and confirm the fact that the scientific consensus on fluoridation is not under dispute – except by a relative few professionals and a far greater number of non-professionals who have believed them.
  2. Virtually all major science and health organizations worldwide publically recommend fluoridation as a safe and effective public health measure (many since the 1950s and 60s).

    These organizations include: The World Health Organization which represents 191 countries, the British Dental Association (around 22,000 members), the British Medical Association (over 156,000 members), the Irish Dental Association (over 1,800 members), the American Dental Association (over 114,000 members), the American Medical Association (over 200,000 members), the American Academy of Pediatrics (around 64,000 members), the Canadian Dental Association (over 16,000 members), the Canadian Medical Association (80,000 members), The Australian Dental Association (over 11,000 members), the Australian Medical Association (over 28,000 members), the New Zealand Dental Association (2,026 members), and around 100 other organizations and their members.

  3. The hundreds of thousands of members of those organizations have not rebelled.  FOs have provided no rational explanations for why, if the "evidence" they claim actually proves CWF is ineffective and harmful, a significant number of members representing the organizations have not stepped forward to publically
  4. No such reputable science or health organizations support the anti-F opinions.

Additional resources for understanding the benefits and risks of drinking water fluoridation.

FOs apparently have no idea of what constitutes a scientific consensus, how to recognize one or even how to try and refute one.  

All FOs would have to do to support their claim that “there is no consensus fluoridation is safe or effective. There never has been” (Rick North, Lund Report Opinion)  is to list a majority of reputable science and health organizations that accept the anti-F opinions as legitimate. 

However the fact is, according to the most comprehensive list I have seen posted by FOs, support for their opinions consists of 6 alternative health organizations and about 11 advocacy, environmental, marketing, spiritual and cultural organizations and a number of of conspiracy theory fanatics like Alex Jones [INFOWARS], David Icke [Son of the Godhead] and Mike Adams [Natural News]..

Groups and Organizations Publically Opposed to Fluoridation include:

  • INFOWARS, Alex Jones
  • Natural News, Mike Adams
  • AAEM: American Academy of Environmental Medicine
  • ICIM: International College of Integrative Medicine
  • IABDM: International Academy of Biological Dentists and Medicine
  • IAOMT: International Academy of Oral Medicine and Toxicology
  • ICA: International Chiropractors Association
  • HDA: Holistic Dental Association
  • EWG: Environmental Working Group
  • CHEJ: Center for Health, Environment & Justice
  • Children's Health Defense: Anti-vaccination organization, Robert F. Kennedy, Jr
  • Sierra Club: Environmentalists
  • OCA: Organic Consumers Association
  • FWW: Food & Water Watch
  • CAAP: Coalition of African American Pastors
  • LULAC: League of United Latin American Citizens
  • Mercola.com: "Alternative Health" products
  • David Icke [Son of the Godhead]

Below are some critiques of a few high profile anti-fluoridation, anti-science individual supporters and groups. Obviously, if you accept the beliefs and positions of these individuals and organizations you will dismiss these critiques.  However, if you have any interest in understanding legitimate scientific and health positions based on an impartial evaluation of scientific evidence, it is worth examining the overall context of anti-science propaganda of all types as described below

Fluoride Action Network & Paul Connett, New York State Coalition Opposed to Fluoridation and other ant-F organizations and activists:

Mike Adams (the “Health Ranger”) and Natural News:

Alex Jones and Infowars:

Joseph Mercola and his alternative health empire:

David Icke and his conspiracy theories:
"David Icke is a human singularity of insanity best known for his "reptoid" conspiracy theory. He came to fame as an English footballer and sports commentator and used to be a spokesman for the Green Party of England and Wales, but since 1991 has devoted his life to informing the world that it's actually secretly controlled by evil shape-shifting lizard-people from the 4th dimension."
"In 1990 Ickesays, a psychic told him he had been placed on earth for a purpose and would begin to receive messages from the spirit world.[9] The following year he announced that he was a 'Son of the Godhead' and that the world would soon be devastated by tidal waves and earthquakes, a prediction he repeated on the BBC's primetime show Wogan. The show turned him from a respected household name into someone who received widespread public ridicule. ... Incidents and issues Icke attributes to the Illuminati, or 'Global Elite', include the Oklahoma City bombing, Dunblane, Columbine, 9/11 (which Icke believes was an 'inside job' to provide an excuse to advance an agenda of regime change across the world), 7/7, global warming, chemtrails, water fluoridation, the death of Princess Diana, the assassination of John F. Kennedy and Agenda 21"

Additional References and highlights of tactics used by fluoridation opponents: