Fluoridation Facts

I stole the above title from a newly released American Dental Association (ADA) pamphlet on the controversy about fluoridation of public drinking water. This is another area where people with little understanding of science have spread falsehoods leading to some resistance to a beneficial practice. A brief review of the executive summary makes it quite clear; fluoride prevents cavities.

Although I have never had doubts about the safety of adding fluoride to drinking water, twice a year I am faced with the question of whether to pay an extra $35 at the dentist for a fluoride treatment. I know there is evidence that these treatments, along with the fluoridation of drinking water and toothpaste, are beneficial for children’s teeth, but I wondered about the effectiveness for adults. 

The fact that my insurance company doesn’t pay for it raises some suspicion. Coverage decisions may be based on cost factors, but one cost factor they must consider is higher future dental bills. Normally they would prefer to pay for prevention than to pay more later.

I began my research on the effectiveness of fluoride treatment for adults at a site billing itself as “the top magazine for dental hygiene professionals.” One hygienist, whose boss wants her to push the treatment to increase business, asks directly whether every patient needs fluoride.

The answer goes to an ADA publication from 2007. (The advisor didn’t know of any more recent updates.) A patient whose risk is low “may not receive additional benefit from professional topical fluoride application.” Low risk is defined as "No incipient or cavitated primary or secondary carious lesions during the last three years and no factors that may increase caries risk." It goes on to say there are other factors to consider, but generally “blanket mandates of fluoride for everyone are not appropriate.”

Consumer Reports gives basically the same answer (with less dentist jargon). “Extra fluoride may be helpful if you’re at increased risk of developing cavities, indicated by frequent tooth decay in recent years, dry mouth caused by medications or disease, or gum recession that exposes the vulnerable tooth roots.” 

They go on to say that home treatments are not effective, and that those in the low risk category should do fine by brushing twice a day with fluoride toothpaste “especially if your water is fluoridated.”

The National Center for Biotechnology Information site reviews a compilation of research on the “effectiveness of fluoride in preventing caries in adults.” They believe that the authors' conclusions favoring the use of fluoride treatments for adults “appear to follow from the results presented, although the paucity of more recent studies and poor quality of the included studies limit their reliability and relevance to current populations.” This vague recommendation (also from 2007) is not very compelling.

A Healthline.com page from 2018 asks: “What Are the Benefits, Side Effects, and Recommendations for Fluoride Treatment?” Again the emphasis was on children and adolescents with some discussions of minor side effects of treatments and real dangers of fluoride supplements. A little new information was that it was “best to get fluoride both topically [gel or toothpaste] and systemically [ingested]” from drinking water.

With several references to the 2007 ADA advice, I went there next. In addition to brushing twice a day, flossing and regular dental examinations, a “key to good oral health is fluoride.” Maximum benefit “is achieved when fluoride is available both topically and systemically.” Treatments from a dentist are recommended for adults with high risk factors such as poor oral hygiene, active caries, eating disorders, drug or alcohol abuse, lack of regular professional dental care, high levels of bacteria in the mouth, exposed root surfaces” and a few others.

In my case it seems I have been correct in saving $35 per visit. I eat most of my meals at home, so I am able to brush three times a day. We use fluoridated tap water for cooking food and drinking. (Bottled water is non-existent in the house.) I have not had a cavity in at least ten years. (Knock on wood.) Nor do I have any of the other critical factors or habits.

It’s interesting what a little research – a factor in critical thinking – can do to help with everyday decisions. 

Social Media vs. Reality

Given the choice to believe information passed around by friends, family and Facebook or the often-contradictory information passed around by doctors and experts based on scientific research, why do so many people go with the former?  Some of this effect may be blamed on the prevalence of what used to be called old wives’ tales and later urban legend, but are now sometimes referred to as a "psycho fact" – defined as a belief in the truth of an assertion based only on constant repetition.  A textbook example of a psycho fact is the myth that we use only 10% of our brain, an assumption easily disproved by MRI or other imaging technology as well as some common sense reasoning.

Now the formula for Diet Pepsi is being changed, not for any scientific or health-related reasons, but because of the public belief that aspartame currently used as a sweetener is unhealthy.  The company attributes a 5% reduction in sales to this widespread misinformation, so they have no choice but to succumb to public opinion and loudly advertise that they are changing.

In most articles, the press reports this fairly and emphasizes the fact that aspartame is, according to the FDA, “one of the most exhaustively studied substances in the human food supply, with more than 100 studies supporting its safety."  As reported in the Guardian from the UK, “the decision is a canny marketing move to allay the fears of US consumers, rather than one based on science; aspartame will still be used in Diet Pepsi for the rest of the world.”  As with many other substances, when taken in high enough doses, the individual ingredients can be dangerous; but as I have pointed out several times before, even water can be fatal if too much is consumed.

This LA Times report explains how wrong these rumors of danger are and how often they have been debunked.  For example, a 1996 paper purported to link exposure to it to a rise in brain tumors, but the increase in tumors was shown to began in 1973, “eight years before the introduction of aspartame, and mostly to affect people 70 and older -- not a major market for diet drinks. A team from the National Cancer Institute in 2006 found ‘no support’ for the hypothesis that the chemical posed a risk to humans.”  Nevertheless, the fear mongers persist, often quoting each other’s warnings and supposed research as proof of their point.

These aspartame rumors are not an isolated example.  It is just one small example in a growing list of fears driven by a small group of presumably well intentioned, but ignorant people who use fear tactics to promote their agendas.  Consider the bad reputation and continued assault on other safe products and practices:  fears spread about the use of Deet in mosquito repellant; claims by anti-vaccines and anti-fluoridation of drinking water movements; irrational resistance to irradiation as a food purification method, bold lettering declaring problems with milk from rBGH-treated cows, misperceptions about the health effects to animals and children of radiation from electrical powerlines and far too many others to mention.

We are left with a choice.  We can spend our resources worrying about these fabricated dangers in the environment and the food supply, participating in protests, spreading unfounded rumors on social media, and spending money on more expensive products that have been forced to meet every artificial restriction and preference of a non-scientific public; or we can use some critical thinking to look for the real science behind these supposed fears.  Don’t we have enough problems without letting these scaremongers, who may be profiting from the rumors they spread, invent more for us?  And just as the housing boom/bust was not caused by the prudent homebuyer but affected everyone regardless of financial responsibility, this surge in anti-science misinformation on social media, on television and in casual conversation perpetuated by an increasingly gullible public will have long-lasting and unnecessarily detrimental effects on our economy and our lives.

Science Education

I see so many cases of scientific misinformation and errors on TV, in the press and in advertising that I think it would be a good idea for someone or some organization (perhaps a university or  Consumer Protection Agency) to provide high school science teachers with a set of weekly topics.  The thrust would be how to protect yourself against fraud and misinformation – how people will try to use your lack of understanding of science to mislead, trick and cheat you.  If you don't understand science, no one will help you.

Here is a shocking example from a newspaper report from earlier this year (May 7, 2013) showing how sloppy journalists can be about science.  Dateline Cape Canaveral, “Two robotic U.S. rovers are back in business on Mars after a month long solar blackout that blocked communications with engineers back on Earth [due to] a solar conjunction [when the] sun in early April moved into an orbit directly between Earth and Mars, interfering with communications between the planets."  [Emphasis added].  Really?  The sun moved into an orbit between the planets?  Didn’t the columnist or his editor know better?  This is scary - reporting based on 15th Century science.  With this in mind, how much other, more damaging, bad information is passed along through the sloppiness or ignorance of the press? 

Many subjects, some covered in these posts over the past two years, would be helpful to young adults to keep them from wasting their time and money or becoming unnecessarily panicked.  Suggested topics include:  the placebo effect, pros and cons of dietary supplements, what to look for in properly designed experiments or tests for effectiveness, genetic engineering of food, the pros and cons of organic farming, a brief history of diet scams, the truth about vaccines and autism, fluoride in drinking water, understanding irradiated food, and common scientific myths.  Without an understanding of these subjects along with training in critical thinking as part of a science education, future generations will be vulnerable to deceptive advertising and the pleas from advocates for every crackpot idea that comes along.

What will happen when they step into high school chemistry class and find out that everything in the universe is made of chemicals and that "chemical" is not a bad word, nor is it the opposite of natural or organic – ideas that seem contrary to what they've encountered from family and the media?  It has almost come to the point where science is being replaced by religion in the public mind, not a standard religion, but a new quasi-religion where the truth is based more on what you believe or believe in than what can be scientifically tested.  Unless this behavior changes Americans will continue to waste money and energy supporting products and services backed only by scientific-sounding arguments and celebrity endorsements.  Let's change it early, before another generation is taken in.

Fluoride in Drinking Water

Add this to my series of examples of the battle between public outcry and the scientific evidence.  Here is an anthology of 13 articles on the subject of fluoridated drinking water published by the Center for Fluoride Research Analysis.  They have gathered in a single document “the official policy statements and consumer information on fluoride from the nation’s leading scientific and advocacy organizations that support community water fluoridation.”  (Additional support can be found on the new ADA website.)

A nice summary appears in the AARP document:  “In spite of its well-documented effectiveness and safety, 100 million persons in the United States remained without fluoridated water at the beginning of the twenty-first century.” 

Why would this be?  Part can be attributed to water supplies from private wells, but part is due to negative public reaction to fluoridation.  Another group of well-meaning people stare scientific evidence in the face and stir up opposition based on their personal interpretation of the studies.  As the article from the American Council on Science and Health puts it:  “The combination of a scientifically unsophisticated public and the profusion of easily accessible crackpot information on the Internet is indeed a prescription for disaster.”  The American Cancer Society article reinforces this:  “A review of more than 50 population-based studies…does not support the hypothesis of an association between fluoride exposure and increased cancer risk in humans.”

If so many reputable organizations promote the addition of fluoride to drinking water, where does the opposition come from?  There are, of course, the conspiracy theorists who once characterized it as a communist plot, but many have sincere and well thought out arguments.  The questions we must always ask about such information are: what are the sources, what are their qualifications, and do they have an outside agenda or possible conflict of interests?

Above all we must resist the temptation to stampede into action or opposition without full and reliable information.  See other instances of potential damage from public outcry in such cases as  the “pink slime” (April 2, 2012) and mad cow disease (April 30, 2012) controversies.