Why anti-fluoride conspiracy theories have persisted for over 70 years

There are some conspiracy theories that defy traditional ideological classification, and the anti-fluoride theories are among the oldest that still have currency. Though it is well-established that fluoridated water supplies improve dental hygiene, and that communities with fluoridated water are healthier in this regard, fluoride-phobia still runs rampant. 

Disgraced right-wing broadcaster Alex Jones, during his heyday, would famously and frequently trumpet his fear of fluoride, specifically saying it had caused his IQ to drop. Scan the conspiracy theory pages on Facebook and Reddit and one will stumble upon innumerable anti-fluoride conversations, large and small. They can be inspired by practically anything, from a grassroots movement in Portland, Ore. to a single post about a 2012 Harvard meta-analysis linking fluoridation to neurological disease (by the researchers' own admission, it relied on studies of varied quality). During the Cold War, anti-fluoride citizens' movements often claimed, falsely, that water fluoridation was a Soviet plot.

There are real-world consequences to these beliefs. Studies from Sweden to the United States have consistently found that fluoride helps prevent dental cavities and tooth decay. The Centers for Disease Control and Prevention (CDC) named community fluoridation one of the great American achievements of the 20th century because of the significant role that it played in leading to mass reduction in cavity rates among children and adults. Cohort studies consistently show that fluoridated water reduces the risk of tooth decay, cavities and tooth loss in both adults and children. However, only 63.4 percent of Americans receive fluoridated water, according to 2018 Centers for Disease Control and Prevention (CDC) data.

Yet fluoridation is not without its drawbacks: There are risks associated with too much fluoride being put in water supplies, with a 2019 study in Mexico and Canada that focused on possible links between fluoridation and brain development issues concluding that "neurotoxicity appeared to be dose-dependent." The study warned that safe levels of fluoride concentration in drinking water are likely to actually be lower than the commonly accepted and recommended amounts. The Environmental Protection Agency (EPA) mandates as a "current enforceable drinking water standard" that fluoride amounts should not exceed "4.0 mg/L," but the Sierra Club argues that this standard is much too high.

When all is said and done, however, fluoridation has overall been a net gain for public health, even if in certain regions the execution has been faulty. Nicole Johnson, an associate director at the CDC who works in their Division of Oral Health, told Salon by email that fluoridation "has made substantial contributions to narrowing oral health disparities and is a practical, cost-effective, and equitable measure that communities can take to prevent tooth decay and improve residents' oral health."

Want more health and science stories in your inbox? Subscribe to Salon's weekly newsletter The Vulgar Scientist.

Given that community fluoridation is such a public health triumph, why do conspiracy theorists still target it? Part of the problem is that the internet is a fertile breeding ground for every type of misinformation out there, with anti-fluoride conspiracy theories being no different.

"Regardless of the topic, vetting and validating online information is important," explained Dr. Corey H. Basch, chair of the Department of Public Health at William Patterson University and an expert in analyzing health-related YouTube information. "Misinformation and disinformation are rampant problems that have a range of ramifications from confusing the public to fueling violence and hatred. If online information is presented in a way that promotes dialogue and respect, this can be beneficial, but unfortunately this is often not the case."

Basch later added, "Based on the research I have conducted, misinformation about fluoride persists on-line and it is typically embedded in a larger debate about community water fluoridation."

In addition to benefiting from the intellectual anarchy of the internet, anti-fluoride conspiracy theories are also propped up by a long history. Indeed, anti-fluoridation conspiracy theories even managed to precede the actual dawn of fluoridation itself. When Grand Rapids, Mich. became the first American community to put fluoride in its water supply in 1945, the city leaders already knew there would be backlash because it had managed to materialize prematurely. Citizens who mistakenly thought the fluoride had been added weeks earlier were already complaining of sore gums and chipped tooth enamel, blaming a fluoridation program that had not yet been implemented.

Not surprisingly, once fluoridation was widespread, some figured out how to make their complaints seem plausible. A conservative Democratic congressman, James J. Delaney, held a series of hearings in 1952 where seemingly "gotcha" questions were asked of scientists to discredit the practice of fluoridation. Conservative political activist and FBI agent Dan Smoot asserted in 1959 that fluoride had been introduced to the water supply after leftist authoritarians had asked themselves, "How could ruling authorities ever manage to give drugs to an entire population?" The John Birch Society, a popular far right conspiracy theory group at the time, endorsed Smoot's views.

Yet as evidence rolled in that fluoridation had improved community dental health, more communities began to implement fluoridation programs. By 1960, 41 million Americans out of a population of nearly 180 million drank from fluoridated water supplies. By 2008, that number had grown to 72 percent of the total population. Throughout that period there has been considerable pushback, but today any American can find out if their community is fluoridated through the CDC's My Water's Fluoride link. It includes information through 2018  — as of that year, the CDC estimates that 207,426,536 Americans (out of roughly 326.8 million) drank from fluoridated water supplies (the 2020 data is expected to be released in the fall).

Today anti-fluoride conspiracy theories are still prevalent, but nowhere near their mid-20th century peak.

"As far as fluoride, I would not be as worried as I would be in the early 1960s when the John Birch Society was in its heyday, and fluoride was not as ubiquitous in our society," Dr. Ted Miller, a history professor at Northeastern University, told Salon by email. He argued that the advantages of fluoridation are widely perceived; and, as such, "I don't think we are going to abandon the salubrious benefits of fluoride overnight."

Basch observed that the argument over fluoridation today often fixates on communal water sources, and has similarities with other public health fracases. "What fuels the debate about community water fluoridation is the argument about the right to make an informed decisions about if and how one wants to receive fluoride," Basch noted. "The political and emotional nature of the debate is accompanied by misinformation and disinformation, which mirrors what we have seen in current debates on vaccination in general and COVID-19 vaccination more specifically."

While scientists continue to monitor the effects of fluoridation, even those who advise caution — such as Dr. Junhewk Kim, author of a 2021 paper on fluoridation — still note that overall community fluoridation has advantages.

"I do not think there is any general risk, if the procedure for administering fluoride to the water supply is properly managed," Kim told Salon by email. "However, there may be locations where fluoride is overutilized. If the water fluoridation policy is combined in areas where high-fluoride toothpaste and fluoride gels and varnishes use in dental clinics are common, there is a possibility that a weak level of fluorosis will occur, in children especially." Fluorosis is a cosmetic condition in which one's teeth appear to have small speckles on them. 

Kim added, "However, when we ask which poses a greater oral health risk to children between mild fluorosis versus dental caries [tooth decay], of course the latter has significant bad impact to oral health. Therefore, I think mild fluorosis is a tolerable risk."