After officials in Grand Rapids, Michigan, began adding small amounts of fluoride to the city’s water in 1945, the number of tooth cavities dropped by an astonishing sixty percent . Since then, water fluoridation has become a standard practice all across the country. Despite the evidence that fluoride prevents tooth decay, many arguments against its benefits have surfaced over the years , and have prompted some communities to stop adding the mineral to their water.
In 2007, residents in Juneau, Alaska, voted to stop putting fluoride in their drinking water . It had been a topic of debate in the city for years, and residents were concerned about the potential harms fluoride might be causing them .
“I’m not against applying fluoride topically as needed,” said Emily Kane, a Juneau-based naturopathic physician and fluoridation critic. “But I didn’t think it was good judgment to medicate the entire population.” 
The research on water fluoridation and the prevention of cavities is plentiful, but not much work has been done to study the opposite side of the argument. In other words, what happens when a population stops putting fluoride in their water?
Jennifer Meyer from the University of Alaska Anchorage saw this as a perfect opportunity. Meyer and her team assessed medical and dental claim records of patients under the age of eighteen in 2003, which was before fluoridation was stopped, and compared them with the claims made in 2012, five years after the anti-fluoride bill was passed .
The results of the study found that after fluoride was taken out of the water, the number of tooth caries increased by an average of one per child per year. The difference was even more notable for children who were less than seven years old.
The Argument Against Fluoride
If water fluoridation is so closely linked to a decrease in cavities, why are there so many people who argue against it? There are many myths that have surfaced one way or another surrounding fluoride that have persisted despite dental professionals’ warnings.
- Fluoride isn’t natural. Many people believe that fluoride is some kind of man-made chemical that isn’t good for us. The reality is that fluoride is a naturally occurring substance found in rocks. It leaches from the rocks into the water, and the levels of fluoride in the water depend on whether it is groundwater or surface water, and on what type of rocks and minerals it comes into contact with.
- Fluoridated water cause cancer. Studies that have shown adverse health effects due to fluoridated water were conducted in areas that had naturally occurring fluoride levels that are up to ten times greater than the optimum levels required to maintain dental health . There is reliable evidence from the World Health Organization that has shown, however, that optimal levels of fluoridation (0.6-1.1 parts per million) were not associated with cancer or any other health complications . This statement has been backed up by other organizations like the World Dental Federation , the Australian Dental Association , and the Center for Disease Control and Prevention (CDC) .
- Fluoridated water is not safe to use in baby formula. Infants are at greater risk for dental fluorosis (weakened teeth due to excess fluoride), which has caused some people to be concerned. The CDC has confirmed, however, that it is safe to use fluoridated water for infant formula, but if you are very concerned, you could mix this water with low-fluoride bottled water .
- Fluoridated water doesn’t work. This argument has persisted because up until now there have been very few opportunities to study what happens when fluoride is not added to water . The work done by Meyer, however, is now demonstrating the negative impact it can have .
The High Cost of No Fluoride
While one extra cavity per child per year doesn’t seem like much, when you consider that the average cost of a cavity-filling procedure is three hundred dollars, it really begins to add up .
“The cost to have a fluoride management program, to actually fluoridate the water, is pennies by comparison to what it costs to treat a cavity,” Meyer told KTOO” .
There are other options to prevent tooth decay, such as fluoride tablets from the pharmacy, but there is much more work involved.
“You gotta get the prescriptions filled, you gotta remember to give it, you’ve gotta make sure kids don’t take more than one – you know, there’s risks to that… It sets up a precedent for inequity,” Meyer explained .
The authors of the study hope that the results from their work will be enough to convince officials in other cities to keep adding fluoride to their water.