SO WHAT IS THIS ABOUT, EXACTLY?

[ I recently read a bunch of papers showing that trigger warnings are, as I always suspected, at best useless or otherwise actually harmful. ( 1, 2, 3 ) That being so, here’s your trigger warning: The following is about one potential consequence of the recent US election. ]

To my mind, among the funnier moral panics of the last week or so has been around some of RFK Jr's interests. The thing the late night and newsroom class are currently wetting their pants about is water fluoridation and the fact that Kennedy, a Trump team insider, announced he’d like to see the practice end.

So why do I find this so funny? Well, largely because folks who know nothing about the matter are pretending, as ever, they’re experts or at least have an informed opinion (or maybe they just know what the popular consensus is) and are reflexively claiming that artificial fluoridation of the water supply is like water itself: essential to life. Unanimously, they tell us water fluoridation is “one of the greatest public health achievements of all time.” The only reason you have teeth, and thus are capable of eating, according to some of these folks, is because infinitesimal amounts of this substance is added to your drinking water by municipal authorities. And they seem so certain of this, seemingly, only because Kennedy is saying the opposite.

They assure themselves and the world by asserting “He’s not an expert! He’s not a doctor! He's not a dentist!” They do so in their mocking tone to imply he’s nothing but a crank and a fool. They say this, of course, while being ignorant of or denying the research Kennedy himself cites along with all the evidence on offer by the very experts they would go to if they actually cared to understand the issue: local and federal health authorities, schools and institutes of public health, international medical review organizations, and others.

FLUORIDATION RATES

Okay, so what do we know? According to the US CDC, only around 63% of the American population has access to fluoridated water. And, like so many things, the situation varies dramatically from state to state. In Hawaii, for example, only 8% of the population is on community water systems that amend their water with fluoride while in New Jersey the rate is only about twice that. At the other end of the spectrum you have places like Kentucky, West Virginia, and Ohio where the rate is above 90%. Right. Given the present rhetoric, is any of that (either the fluoridation rates or the places with those rates) what you would have assumed? If not, what else are you missing?

Now to get a sense for what this means and how the US compares to a peer nation with similar standard of living, water supply, and dental practices, we might look at her neighbour, Canada. Water fluoridation is actually far less common here than in the US. According to the Public Health Agency of Canada, as of 2022, only “38.8% of the population has access to fluoridated water.” Most folks in Ontario and Manitoba (roughly 70%) have treated water. In Alberta and Saskatchewan rates of fluoridation are closer to 40%. And in Quebec and British Columbia virtually no one (around 1%) has water that is fluoridated.

So Canada doesn't really fluoridate the water supply. And, anecdotally, it just doesn't seem to me like British Columbians, with the lowest fluoridation rate, have been suffering from chronic tooth decay for many decades; certainly not obviously so or well beyond what you would see in places who do treat their water. And so if all of the US dropped their water fluoridation rate by half over night they would only find themselves about where Canada is at with fluoridation. And, of course, eliminating the practice entirely would land them pretty close to the situation found in British Columbia and Quebec. Does that sound catastrophic to you? To me it sounds more like something's not right with this narrative I'm hearing at the moment that tells me water fluoridation is essential to oral health (as well as human wellbeing and even survival).

THE EVIDENCE

On the situation here in BC specifically, there’s a good little summary document from the provincial government covering fluoride and water quality. There they offer some relevant background, such as that fluoride is among the most abundant substances in the earth’s crust and is detectable in virtually all minerals. You'll also learn that not only do volcanic eruptions gift us fluoride from deep inside the planet but the weathering of many rock types results in the natural fluoridation of effectively all our sources of fresh- and saltwater. Fluoride, they explain, even comes down in the rain. In fact, as a result, so ubiquitous is fluoride that it actually shows up in all (not some of most) of our food. This provincial fluoride document even explains how there can be so much fluoride in food and other consumables that you can pretty easily exceed public health authorities' daily intake recommendations. They tell us:

Two cups of tea made from the highest fluoride level tea leaves would exceed the recommended daily fluoride intake. The use of fluoridated water supplies in food preparation can double the level of fluoride in prepared foods. Vitamins, toothpaste and pharmaceuticals also add to the daily fluoride dose.

Relating to testing the benefits or harms and particularly whether fluoride is essential to humans, the report also explains that, “Due to the ubiquitous nature of fluoride it is very difficult to prepare fluoride-free diets to test the hypothesis that fluorine is an essential element … If it is essential only very low levels are required.”

Though this document is full of interesting details of this sort, mostly citing work from the '50s through '70s, it suffers from a lack of current research. And it turns out that's a real problem. A much more recent review published by the Harvard School of Public Health (appeal to authority much?) highlights an analysis of 20 key studies investigating water fluoridation. They point to the finding that most of the studies of water fluoridation were conducted prior to 1975 (when toothpaste with fluoride became far more ubiquitous) and that many of those were also plagued with deeply flawed methods and reporting. To help spell all that out they point to the fact that countries who fluoridated their water (like the US, UK, and Australia) saw the same decline in rates of tooth decay in the five decades since then as countries who did not (such as Finland, the Netherlands, and Germany.) Interesting, right? So something beyond the fluoridation of the water supply has to have occurred. And, as such, it looks like people ("proper scientists" interpreting "the science") are confusing correlation with causation. Right. So, in light of this simple fact, of a more universal decline in tooth decay, I would think the whole discussion should be put to bed once and for all.

More than that, the same Harvard review goes on to discuss the evidence for potential harms caused by overexposure to fluoride. They note:

Perhaps most worrisome is preliminary research in laboratory animals suggesting that high levels of fluoride may be toxic to brain and nerve cells. And human epidemiological studies have identified possible links to learning, memory, and cognition deficits, though most of these studies have focused on populations with fluoride exposures higher than those typically provided by U.S. water supplies.

(You might notice the above is neither my own wacky interpretation of the evidence nor the uneducated opinion of the science writer publishing in Harvard Public Health Magazine...)

Seeking more information, I pulled up the publication cited in the Harvard review. It’s published by Cochrane (the independent international network of health professionals who examine health research: aka “the experts.”) The paper is titled Does adding fluoride to water supplies prevent tooth decay? Importantly, no studies aiming to determine the effectiveness of water fluoridation for preventing cavities in adults even met the review’s inclusion criteria. But they did look at 156 fluoride-related studies. Their key findings from this review were that:

• Due to the increased availability of fluoride in toothpaste, mouthwash, and dental treatments since 1975, it is unlikely that at present water fluoridation has any measurable impact on tooth decay.

• There is no evidence of any kind for increased tooth decay among a population when fluoride is removed from a water supply.

• Adding fluoride to water may lead to slightly less tooth decay in children’s baby teeth; but there was no evidence that doing so reduced tooth decay in children’s permanent teeth or decay on the surfaces of those teeth.

• Studies looking at the number of children who have no tooth decay at all, in either their baby teeth or permanent teeth, suggest that the fluoridation of water may have either a very slight impact or none at all.

More recent still is another report, another review of prior research, published this summer by the US National Toxicology Program, a branch of the US National Institutes of Health. This is the research that sparked Kennedy’s interest and was cited by him in various interviews and podcasts, that looked at the negative impacts of fluoride overexposure. That report suggests high levels of exposure — more than double the recommended water concentration of 0.7 milligrams per litre in places like Canada — are associated with a possibility of a slight diminishment of intelligence in children, like 1-4 IQ points, but with no such declines in adults. The review is also very clear when it states that we just don’t have good data on fluoride at this time and that “More research is needed to better understand if there are health risks associated with low fluoride exposures.”

So all of that does not appear to be a strong argument against fluoridation of the water supply, if you ask me; though, of course, none of it (that it doesn't seem to prevent cavities and is already in all our dental products and everything we consume and many places don't fluoridate and have no apparent tooth decay problem) amounts to an argument for fluoridating our water, of course. So what exactly are the strongest arguments for water fluoridation?

SUPPORTING ARGUMENTS

On this topic, I found an offering from McGill university, out of their Office for Science and Society, and published just a couple of weeks ago. It’s pretty unsatisfying. For example, they simply assert, just as most folks do, that:

The decision to supplement drinking water with fluoride in North America led to a dramatic reduction in cavities and tooth loss over the second half of the 20th century and was declared one of the 10 great public health achievements of the century by the U.S. Centers for Disease Control and Prevention.

As stated earlier, there’s just no evidence for any of that. That’s contrary to the above Harvard review pointing out that tooth decay declined with the introduction of fluoride but irrespective of water fluoridation programs around the world. So, at best, this opening remark is an assumption that confuses correlation with causation. A rough start, that. The strongest argument in support for water fluoridation they offer comes when they claim:

…we add fluoride to drinking water for the same reason we add iodine to salt and folic acid to grains: It is the most effective way to ensure all members of society have equal access to necessary medical care. It is easy to say “go buy toothpaste” when you have a comfortable income, but access to dental care is a luxury some cannot afford. Fluoride supplementation is not only the most cost-effective way of distributing fluoride to the population, it’s also the most equitable. 

Though that’s an emotionally appealing argument, I don't think it holds water and for a whole bunch of reasons. Firstly, as stated earlier, “we” don’t fluoridate our water. Secondly, the poorest among us, without access to toothpaste, are not sitting around bathing their teeth in tap water (the overwhelming majority of which is not fluoridated.) Lastly, popular stores all across the country and accessible to effectively everyone, offer a tube of fluoride-containing toothpaste for $0.84. If that’s so, then at two brushes per day a 60ml tube will last an individual almost four months, meaning their toothpaste budget will land around $0.23 per month or a little less than $0.06 per week). CAVEAT: I didn’t look for cheaper alternatives to a couple of bucks per annum but those may exist. And I didn’t look to see if you can buy this stuff in bulk for half the price, either... 

As such, this present panic over fluoridation looks to be about anything but public health or the existing evidence. So what is all of this noise about, exactly?

(Thank God I #DidMyOwnResearch and didn't wait around for Bill Maher or Stephen Colbert, the Atlantic or CBC to spell out the most basic details of what they insist is a health- or life-threatening policy decision with severe impacts for millions of people — all set to be implemented by a pack of fake politicians and faux-epidemiologists telling you they seek to save lives even as they do everything they possibly can to harm them. *Phew*)