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Linus and Simone (children)
My favorite flavor toothpaste is probably blue, raspberry, or bubblegum. I like watermelon, strawberry, cherry, mango.
Interviewer/Adult Questioner
What is the worst flavor of toothpaste
Linus and Simone (children)
but
Interviewer/Adult Questioner
boogies, those are not flavors of toothpaste.
Thomas Goetz (Host/Narrator)
This is producer Rachel Swaby with her two kiddos.
Dr. Esther Machen (Dentist)
Where are we?
Linus and Simone (children)
I'm in my house, the bathroom.
Interviewer/Adult Questioner
What is your name and how old are you?
Linus and Simone (children)
Linus, and I'm nine. Simone and I'm 25. My name is Simone and I am five.
Thomas Goetz (Host/Narrator)
Rachel and I wanted to know what do kids actually understand about their teeth? Adults, we understand we should brush our teeth twice a day and floss and go to the dentist for an annual checkup. And parents know they should teach good habits to their children when they are three or four years old. This is all dental dogma, but what do kids actually understand about all that? And so Rachel asked her kids, why
Interviewer/Adult Questioner
do we brush our teeth?
Linus and Simone (children)
To make sure we don't get cavities and our teeth don't fall out.
Interviewer/Adult Questioner
What is fluoride?
Linus and Simone (children)
I don't know. You ask me.
Interviewer/Adult Questioner
Do you have any guesses what fluoride is?
Linus and Simone (children)
Stuff that helps you.
Interviewer/Adult Questioner
What does it do to your teeth?
Linus and Simone (children)
Creates, like, a protection for your teeth. If you put, like, toothpaste on it, it's like medicine and helps your teeth get clean.
Interviewer/Adult Questioner
What happens if we don't brush our teeth?
Linus and Simone (children)
Sugar bugs. And our teeth fall? Oh, yes.
Thomas Goetz (Host/Narrator)
All giggling aside, this is actually a really good explanation. Simone is dead on. The bacteria that cause tooth decay are basically sugar bugs. And Linus is correct about how fluoride works. So if these two are typical. And of course, Rachel, in no way are your kids typical. They are truly exceptional. But many kids have a decent understanding from a very young age of why brushing our teeth with a fluoride toothpaste is good for us. Adults understand there's a difference between knowing we should brush our teeth twice a day and floss at least once a day and actually, you know, doing it.
Linus and Simone (children)
Brush your, brush your teeth down. Brush your, brush your teeth down. My shark is brushy.
Interviewer/Adult Questioner
Oh, let's see you do it.
Linus and Simone (children)
Squirt, squirt. Can you help me?
Thomas Goetz (Host/Narrator)
Welcome to Drug Story. I am Thomas Goetz. Today's drug is fluoride. You may not think of fluoride as a drug, but it fits the bill. The Food and Drug Administration, the fda, classifies fluoride as a drug, an essential nutrient to human health, and it regulates its use in significant doses. Fluoride needs to be prescribed like any drug or medicine that can cause harm. So, yeah, It's a drug. Now, I'll be honest. When we considered an episode about fluoride, I did not know all that much more than Simone and Linus. I knew fluoride was good for our teeth, that it makes our teeth stronger, and I knew that it was somewhere on the periodic table of elements. Actually, I was wrong there. That's fluorine, the elemental gas form, and that is super dangerous and toxic. Fluoride is the stable ionized version of fluorine. Anyway, I knew that it was in our water. Fluoride is commonly added to tap water as a public health measure and fluoride has been a big success there, among the biggest success stories in public health and medicine in history, in fact. But there was clearly a lot I did not know. Like it turns out fluoride is in most water systems in the US but not all. And it is a very recent thing. In the span of history, before around 1945, fluoride was just not a thing. And while the US has had a lot of success with fluoride, it is actually not added to the water in many other countries. Most countries, in fact, don't have fluoride in their water. And this is a spoiler, but stick with me here. Many of those non fluoridated countries have pretty much the same rate of tooth decay as the US which is something we will try to explain in today's episode of Drug Story. We're going to bite into fluoride, a mineral that has provided massive benefits but also has generated decades of controversy. This episode will celebrate public health and science, but also serves as a warning. We will just dip our toe into the politics while not trying to get too political. Four out of five dentists recommend that you stick around.
Singing Voice/Commercial Singer
When you wake up in the morning, it's a quarter to one and you want to have a little fun. You brush your teeth. You brush your teeth. When you wake up in the morning, it's a quarter to two and you want to find something to do. You brush your teeth. You brush your teeth.
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Thomas Goetz (Host/Narrator)
Welcome back to Drugstore. If you are a new listener, every episode of Drug Story comes in three the diagnosis, the prescription, and side effects. This is part one, the Diagnosis, where we explore the disease behind the drug. Today, that disease, that condition, would be tooth decay, or as it is known medically, caries. That is Latin for rotten or decay. That's what tooth decay is called. As a disease, caries. You learn something every day. Now, when we think of cavities, it probably reminds you of some unpleasant times in the dentist's chair. You probably rank getting a cavity filled somewhere between unpleasant and miserable. A couple Novocaine injections into your gums, some drilling and filling, and at last you are on your way. Well, I am here to tell you what we experience today is a proverbial paradise compared to what people went through just a few decades ago, like just 75 years or so when your grandparents were alive. Because if I ranked modern dentistry on the list of humanity's most amazing achievements, it would be in the top 10, maybe the top three, ahead of the moon landing or television. In fact, I want to convince you that dentistry is among our most successful scientific triumphs in terms of how much human suffering and misery it has alleviated. And it may also rank as the most taken for granted. But to make my case, I may have to gross you out a little bit. So steel yourself. In many ways, the history of dentistry is inseparable from the history of agriculture, because what people ate and where and when that determined the condition of human teeth. Because food doesn't just feed us, it also feeds the bacteria in our mouths. In the days of our hunter gatherer forebears, the general diet didn't contain many carbohydrates or sugars, with the exception of maybe stumbling upon the occasional beehive. Ancient peoples ate some meat and a lot of foraged food. They did not lack for fiber in their diets. Most dental issues, according to archaeologists, stemmed from tooth wear, from all that chewing, rather than from cavities or caries. The invention of agriculture changed all of that. Beginning around 12,000 years ago, different cultures around the world domesticated and cultivated a variety of crops. Wheat and barley in the Middle east, rice and taro in Asia, corn and potatoes in the Americas. They were all carbohydrates. Human farmers grew these crops because carbs provide ample energy. Reliable stores of energy, rich foods sustained early societies and allowed civilization to emerge. But carbohydrates are not good for our teeth. And that was especially true in a time before toothpaste. Studies of fossil skeletons from ancient societies in Sudan, Africa found that around 10,000 years ago, when the Nubian people began farming more intensively, well, there was a pronounced change in dental health. Before agriculture, less than 1% of fossil skeletons showed evidence of tooth decay. After agriculture, that number increased to nearly 20%. The connection between food and cavities was not obvious at the time, though. For millennia, many societies around the world, ancient Egypt, China, Babylon, Europe, they all independently came to the notion that tooth worms were the culprits of cavities, invisible creatures that somehow bored into human teeth. It was a good guess, but no, tooth worms do not exist today. We know what causes cavities. Here's a quick bit of dentistry 101. Bacteria in the mouth form a film on the surface of the teeth that's known as plaque. Bacterial plaque feeds on carbohydrates, that's starches and sugars in the mouth. And as the microbes digest the carbs, lactic acid is a byproduct. That acid degrades the enamel coating of the teeth. Now, over time, as the enamel breaks down, eventually there's a hole in the tooth that's a cavity. You can think of caries as the disease and the cavity as the result. Now, today, with access to dentists, you get that cavity filled, problem solved. But before modern dentistry, for billions of people across thousands of years, a cavity would just fester. Or actually even today, in the absence of dental care. So here's what's happening. The cavity creates a hole, an open wound, a literal cavity in your tooth. And with every meal, bits of food get stuck in that space and the bacteria keeps eating and the acid keeps dissolving deeper into the tooth, through the enamel, through the dentin layers below, down into the pulp of the tooth. That's the living flesh in the core of the tooth, and it is full of blood and nerves. Many, many nerves. So now you have bacteria and living tissue. Well, this is a volatile mix, because the tooth pulp is typically where an infection starts. As the infection takes root, the tooth begins to die, and the pulp tissue, it's a goner. And here comes the pain. Oh, my God. The pain of a toothache. It's been described as the hell of all diseases. Here's a bit of William Greenway's 1994 poem, Toothache.
William Greenway (Poet)
I think of the Civil War, the amputations without anesthetic, or the lonely, swollen faces by firelight. No pill but prayer, no end or even sleep in sight. Holding their pain inside, gobbing blood onto coals. The world collapsed into a black pinhole inside their heads.
Thomas Goetz (Host/Narrator)
Let's compare it to when, say, your finger or knee gets injured and infected. That is the body's immune system kicking in, and the tissue gets inflamed and swells up. That's part of how the body heals itself. Usually, the immune system defeats the bacteria, the swelling subsides, and you are on your way. But an infected tooth, it cannot swell. An infection in the pulp of a tooth is locked inside the rest of the tooth. And this is why a toothache is its own kind of misery, and there is no going back. Unlike an infected cut, a tooth infection really cannot heal. People took opium or laudanum to deaden the pain. They took arsenic to kill nerves in the mouth, often with deadly consequences. The infection, it will only spread. The gums can become infected, or the infection could spread to the jawbone below. Death by mouth infections was woefully common, maybe around 10% of all deaths back in 17th century England. Which brings us to primitive dentistry, which is to say dentistry from eternity. Until, say, about 1850, this was a brutal business. Dentists would file the edges of a cavity down, hoping less food would get stuck in there. They would stuff the cavities with wax or herbs. Now, today, you can get a root canal where a dental surgeon removes the infected pulp and then cleans and seals the tooth. But back before modern dentistry, there was really only one thing to do. Pull the damn tooth out. And remember, all of this was in the eons before Novocaine or anesthesia. It must have been miserable. And then things got even worse. With the invention of industrialized Sugar in the 16th and 17th centuries, sugar plantations began to explode across the Americas to feed the world's insatiable appetite for sweet stuff. Sugar may have tasted divine, but it was hell for humanity's mouths. The more affordable sugar became, the worse people's teeth got. Sugar is especially bad for human teeth because bacteria love it as much as we do. The more sugar in the human diet, the more acid bacteria release into our mouths and the faster unclean teeth decay. By the mid-1700s in Europe, rampant decay was utterly common in children and young adults. Their teeth would turn black and just rot away. One tooth after another. Rudimentary dentures. Think here of George Washington and hippo ivory. They were the only alternative. As PJ o' Rourke famously wrote, if you think that in the past there was some golden age of Pleasure and plenty. Let me say one single word, dentistry. Now, like a lot in medicine, things began to change at the end of the 19th century with the discovery of bacteria. Very quickly, caries was understood as a bacterial disease, a process, one that could be prevented or at least interfered with. Goodbye tooth worms. Hello toothbrushes and toothpaste. Over the centuries, here or there, there were fledgling examples of dental hygiene. Toothpicks have been common around the world, which makes sense. Nobody likes food stuck in their teeth. Also, tooth sticks were used for millennia. Bits of wood that people would chew on as a way to sort of clean their teeth. Toothbrushes were most likely invented in China around the year 900. Made of bamboo and boar's hair, they look very similar to those fancy eco friendly toothbrushes at Whole Foods. But with an understanding of bacteria, people started to get serious about their teeth. In the late 1800s, the first mass produced toothbrush in the US was the prophylactic. First sold in 1888. A few years later, Colgate released Colgate Ribbon dental cream, the first toothpaste sold in a tube. This was the beginning of what we now know as modern dental hygiene. Toothbrushes and toothpaste and dental floss. Patented by Johnson and Johnson in 1898, this created an arsenal for dental defense. But it would take another 50 years for the final weapon to arrive. Fluoride. A magic ingredient that would transform the whole idea of public health and of dentistry. We'll get to that in part two. And to take us there, here's one of the first commercials from the first toothpaste to contain fluoride. Not Colgate, but Crest. And no, they are not a sponsor of this episode. This is not a paid commercial on Drug Story.
1960s Crest Toothpaste Commercial Announcer
In several Western towns, children rarely got tooth decay. Why their drinking water contained fluoride. Now, after years of fluoride research, Procter and Gamble proudly announces triumph over tooth decay for everyone everywhere as it brings you. Crest Toothpaste with florestan, its exclusive fluoride compound that's far superior to fluoride alone. Here's how Crest works. Crest with florestan actually combines with.
Thomas Goetz (Host/Narrator)
Welcome back to Drug Story. This is part two, the Prescription, where we dig into the drug in question. Today's drug is fluoride. So the discovery of fluoride is one of those happy accidents, a combination of coincidence and scientific curiosity that changes life as we know it. Like the discovery of penicillin and insulin and the smallpox vaccine. This tale starts in 1901 with Dr. Frederick McKay, a young dentist who heads west to make something of himself, Dr. McKay landed in Colorado Springs, Colorado, a boom town that a recent gold rush had transformed into a growing city of 20,000 people. That was great news for Dr. McKay. There were plenty of mouths to work on. And Dr. McKay soon realized he had his work cut out for him. The teeth of many residents, particularly those who had grown up in Colorado Springs, they were stained brown, as dark as chocolate. Nearly 90% of children in town had stained teeth, Dr. McKay estimated. And Colorado Springs wasn't alone. Other towns around the state also seemed to suffer from the blight. So Dr. McKay called this Colorado stain, and he would end up spending years investigating the problem. Various theories came and went. Too much pork in the diet, too much calcium in the water, Bad milk. It took him a decade to document that those with mottled brown teeth also had much lower rates of tooth decay. A curious finding that he still could not explain. Eventually, McKay's research reached a chemist at Alcoa, the aluminum company of America. He offered a more sophisticated water test. Finally, in 1931, McKay had the answer. The water in Colorado Springs contained exceptionally high levels of fluoride. It only took 30 years. This news caught the attention of a dental surgeon at the National Institutes of Health by the name of H. Trendley Dean. Where McKay had originally thought Colorado stain was something to eliminate, Dean fixed on a possible benefit. If the fluoride protected teeth from decay, perhaps there might be an ideal level of fluoride that would protect tooth enamel without staining the teeth. They began a nationwide investigation, examining dental records and water quality in cities across the United States. After a dozen more years, Dean had found his Goldilocks level. Teeth stayed white, but also withstood cavities at one part of fluoride per million parts of water. And that gave Dean a new idea. If some towns had this level of fluoride in their water naturally, maybe adding fluoride to the water system in a city without fluoride, maybe that could prevent tooth decay in the local population. This was an audacious idea. But in 1944, it seemed altogether possible. The American century was in full bloom, and the might of American science and industry was on the verge of triumph in World War II. Why not try something audacious? They just needed a place to test the idea. Pretty quickly, Grand Rapids, Michigan, rose to the top of the list. Now this was a different time. FDR had just been reelected to his fourth term. Michigan was booming, thanks to the auto industry and the war effort. And faith in the federal government was never higher. People believed good things were possible. What's more, Grand Rapids had no natural fluoride in its water at the time. And accordingly, dental health was really bad. And so the city's leaders signed on.
Dr. Chase Kleinstecker (Dentist)
We used the water from Lake Michigan, which was virtually free of fluoride. And the cavity rate in Grand Rapids was extremely high. The Lake Michigan water was just didn't have any fluoride.
Thomas Goetz (Host/Narrator)
This is Dr. Chase Kleinstecker, a Grand Rapids native and for decades a dentist in the city.
Dr. Chase Kleinstecker (Dentist)
There's one dentist that said that 75% of his practice was just pulling teeth and doing dentures. In the 1930s, at 6 years of age, 80% of the children had an average of 14 cavities. In fact, I knew a doctor, and he had book salad with teenagers on Saturday morning to have all their teeth taken out and to make dentures so they can look nice.
Thomas Goetz (Host/Narrator)
So for dentists in Grand Rapids, the idea of adding fluoride was very appealing. It might help their patients, help children keep their teeth, and maybe even give dentists back their Saturdays. On January 25, 1945, workers at the Grand Rapids waterworks began pouring powdered sodium fluoride into the water system. The powder dissolved in the massive tanks and began flowing out into the city. The experiment was on.
Dr. Chase Kleinstecker (Dentist)
I was in this study because I was five years old in 1945 when they started adding fluid. I was in the study itself and began in kindergarten. And they did quite a few exams. And it was a very thorough study, a 15 year study. And they did a urine analysis, X rays, saliva tests, all kinds of tests to see how if it had any effect on people. And it was probably the most studied public health event of any in history.
Thomas Goetz (Host/Narrator)
And it was indeed a huge success, clearly beneficial, Years before, the 15 year experiment had officially concluded. So the US Public Health Service rolled out a national campaign to spread the word.
News Reporter
This is Grand Rapids, Michigan, A town becoming widely known to dentists and municipal authorities for its fight against tooth decay. The children in Grand Rapids have less tooth decay than they did six years ago, as much as 65% less.
Thomas Goetz (Host/Narrator)
But the federal government did not mandate that all municipalities across the country should fluoridate their water systems. That would have been a bridge too far. Instead, advocates of fluoridation went city by city, town by town. By 1960, 15 years after the Grand Rapids experiment began, fluoridated water reached 50 million Americans, nearly 30% of the population. And that's not to say fluoridation wasn't without its critics or outright opponents. Here's a 1962 film from the American Dental Association.
Dr. Benjamin Spock and others (1960s ADA Film Voices)
Because fluoridation is a public health measure and its adoption in a community is a matter for local governments to decide. Unfortunately, there are strong pressure groups, professional hate mongers and special interest groups who have battled against fluoridation in one community after another. Wherever there is a hearing on a proposed ordinance to adopt fluoridation, they are there with their typically fanatic objections. But for every objection, there is a firm, authoritative answer. It's against the laws of nature. It's an unnatural poison.
Thomas Goetz (Host/Narrator)
You want to feed our kids, you know.
Dr. Benjamin Spock and others (1960s ADA Film Voices)
Tooth decay is one of the main childhood diseases. For centuries, the fluoride that occurs naturally in drinking water in some parts of the country has helped prevent tooth decay.
Thomas Goetz (Host/Narrator)
That last voice you heard was Dr. Benjamin Spock, who was at the time, in the 1960s, among the most trusted medical experts in America. His book, Dr. Spock's Baby in Childcare, it sold 50 million copies by the time of his death in 1998. He even ran for president in 1972. So, yeah, the dentists, they brought out the big guns. The critics, though, they didn't go away. But they were increasingly considered conspiracists in the mold of the John Birch Society. On the radical fringes, they were ripe for parody. Here's Brigadier General Jack d. Ripper from Dr. Strangelove.
Dr. Benjamin Spock and others (1960s ADA Film Voices)
Have you ever heard of a thing called fluoridation? Fluoridation of water?
News Reporter
Yes, I have heard of that, Jack, Yes. Yes.
Dr. Benjamin Spock and others (1960s ADA Film Voices)
Well, do you know what it is? No. Do you realize that fluoridation is the most monstrously conceived and dangerous communist plot we have ever had to face?
Thomas Goetz (Host/Narrator)
Year by year, decade by decade, more cities added fluoride to their water systems. By 2016, more than 70% of American's municipal water systems were fluoridated. American. Other countries added fluoride to their water too, including Australia, New Zealand and Canada. The effect was profound. In Grand Rapids, tooth decay among children dropped by more than 60% nationwide. A similar trend played out over the decades. By the 1970s, 1980s, when I was a kid, fluoridated water and fluoride toothpaste seemed completely normal, totally benign. Where there was once a handful of toothpaste, Colgate and Crest, which, as I remember it, was much mintier than Colgate. Well, now there were new brands arriving on the shelves. Aquafresh, aim.
Aim Toothpaste Commercial Announcer
Look, your little girl's getting grown up. Teeth.
Linus and Simone (children)
Hi, daddy.
Thomas Goetz (Host/Narrator)
Guess what?
Aim Toothpaste Commercial Announcer
You can help guard those teeth against cavities with aim. Aim's Floral Fluoride Gel Acts. Two ways to give her teeth all the fluoride they can get from a toothpaste. First, AIM's unique formula gets fluoride to teeth quickly. Then AIM's great taste keeps her brushing so teeth get fluoride longer. You're doing your best to help keep her teeth healthy and permanent with aim because we're aiming for zero cavities.
Thomas Goetz (Host/Narrator)
And companies began to sell toothpaste to the kids, not just the parents. And so flavors beyond mint started to appear. And that will take us to part three, coming up. First, here's a 1989 commercial for what we think is the first modern toothpaste not to have a mint flavor, Colgate junior. It had a mild bubble fruit flavor, whatever that is. And I always say this, not a sponsor of Drug Story.
Colgate Junior Toothpaste Commercial Singer
Got sparkles in my toothpaste pace and a sorry shake. Your name is K Jr. It's got an awesome taste. Col means it works so bright Jr means it's final worse working all the time. Col Gate Jr for superstars like you.
Thomas Goetz (Host/Narrator)
Welcome back to Drug Story. This is part three, side effects, where we look at the consequences of the drug in question with fluoride. One side effect was invisibility. Insofar as when fluoride works, the impact is invisible. There are fewer cavities, less oral disease. But that raised another question. If everyone is using fluoride toothpaste, is it still necessary to fluoridate the water supply? So let's tackle the invisibility part first. As we said, fluoridated water now reaches about 65, 70% of Americans. In those communities, as many as half of children reach adulthood without a single cavity. But 65%, well, that still leaves about one third of the population without fluoride in their water. And that's mostly in the Mountain West. Visiting some of those spots, it's kind of like going back in time.
Dr. Esther Machen (Dentist)
So I grew up in a town called Chester, Idaho. And that is where there is natural fluoride in the water. And it's about optimal. It's about one part per million.
Thomas Goetz (Host/Narrator)
This is Dr. Esther Machen. She is a dentist in Idaho Falls, Idaho.
Dr. Esther Machen (Dentist)
And so I grew up in a family. We were a logging family. And I had 13 brothers and sisters. And we did not go to the dentist because there was not the funds to go to the dentist. And all of the older siblings, and I'm the fourth oldest, so all of us really had good teeth. It's about when I graduated high school, my family moved to Sanford, Colorado, and there wasn't fluoride in the water there. And I watched my younger siblings so start to suffer with severe tooth decay. I really contributed the tooth decay to no fluoride in the water. And that's one of the things that drove me to go to dental school, was watching my siblings suffer and not really being able to do anything to help them. I remember seeing my brother with large abscesses at the front of his mouth where the teeth just had to be removed because they were so far along in the decay process.
Thomas Goetz (Host/Narrator)
Dr. Machen went to dental school in Kansas City, where they fluoridate the water supply. There, she often treated adults with no cavities. But Dr. Machen and her husband decided to move back home to Idaho, to Idaho Falls, where the water is not fluoridated and there is little natural fluoride in the water.
Dr. Esther Machen (Dentist)
I think one of the things that shocked me the most was moving back to Idaho where they don't fluoridate and recognizing the decay rate. I first noticed it when I very first opened my practice. I opened it from scratch. And so I was just absolutely floored with the amount of decay in the area. And I remember going to my son's kindergarten classroom and looking just at the smiling kids at me, and they had so much dental work done. You know, you'd see the stainless steel crowns everywhere. It floored me because, you know, there was such a need to restore that decay that all the kids had massive restorations in their mouth.
Thomas Goetz (Host/Narrator)
What is a full mouth restoration? Like, what does that mean?
Dr. Esther Machen (Dentist)
Basically, you're putting crowns or fillings in every tooth in the child's head. And so every single tooth that the child has has decay. And so you need to go through and you need to. To restore each of those teeth. That's what we call full mouth restoration. It's actually pretty easy for me to tell if a patient grew up in this area or didn't grow up in this area. Because if I have an adult patient come into the clinic and I do their exam, and they don't have any cavities and never have had a cavity, then I know they probably did not grow up here. And then I explain that we don't have fluoridated water here, and I would highly recommend that they start getting a little bit more fluoride in their diet. But I tell them, I say, you know, if you don't do anything, you'll start seeing decay within a couple years. If they're not using fluoride, then I'll start to see a little decay creep in. Not a ton. They'll be like, wow, I just got my first cavity at 44 or whatever. And I'll just start seeing it creep in.
Thomas Goetz (Host/Narrator)
Not many dentists get to see this kind of before after vision of what fluoride does. But once you see it, it can be very unsettling because she knew that fluoride would help her patients. There was science and experience behind her. So she tried to get local governments to fluoridate their water. And that did not go anywhere because Idaho, well, it's a very conservative state. I would say it's a state that limits government intervention in health, but they have had little trouble restricting women's health rights in recent years. So it's not exactly consistent. But I said I wasn't going to get political. So According to the U.S. centers for Disease Control, about one third of people in Idaho have fluoridated water, among the lowest rates in the country. And for dentists like Dr. Machen, this was a problem she thought she had a solution for.
Dr. Esther Machen (Dentist)
I was able to get started in conjunction with the public health department here, an opt in fluoride program for the elementary students. And so they had to take the paper home. They had to have their parents opt in. So we're not going to give them a fluoride treatment unless they said, yes, I want a fluoride treatment.
Thomas Goetz (Host/Narrator)
So this, this is how it's supposed to work. Opt in, your family's choice. And it was working, but then all of a sudden Dr. Machen learned that the county shut her program down.
Dr. Esther Machen (Dentist)
And do you know who stopped my program? Two pediatric dentists in town. And I was very upset.
Thomas Goetz (Host/Narrator)
Well, wait, why would, why would dentists be against a opt in program that gives kids fluoride?
Dr. Esther Machen (Dentist)
I don't know. But they went to the public health department, protested it and they shut it down. And I don't understand that at all. I simply cannot understand it.
Thomas Goetz (Host/Narrator)
I mean, just guessing, but did it have something to do with their business, their livelihood?
Dr. Esther Machen (Dentist)
You know, that's the only thing I can guess because I think if you read the literature and you study the science behind water fluoridation, I feel like it is a very well studied and thought through program. And it's got a lot of evidence to support how fluoride strengthens teeth and reduces decay. And so I don't understand. That is my only guess, the same as you. So I don't know where you go from there. It kind of just kind of knocks you down and you think, I don't know what to do.
Thomas Goetz (Host/Narrator)
The other factor is that fluoride has again become an object of outsized Indignation and fear. It has some other meaning that is detached from what it actually does, what it actually is for. To get a glimpse of what this looks like here, try this. Go on to Amazon and search for fluoride. There you will see over 8,000 results of mouthwashes and toothpaste and whiteners in so many flavors. There are just a lot of fluoride products for sale. Now scroll back up to that search bar on Amazon and search for fluoride in books. And boom, you have entered an alternate universe. The first result is the case against fluoride. The second result is fluoride drinking ourselves to death. The sixth result is removing fluoride from our drinking water. And it goes on from there. Make America fluoride free again. The fluoride truth. Fluoride harm. As rabbit holes go, this one goes deep. Amazon is basically a proxy for our national brain. It reflects our urges and wants and desires. It's where we put our money, where our mouth is, so to speak. And what Amazon tells us is that America has a split personality. We want fluoride in many flavors and colors and products because, yeah, it protects our teeth. But many of us are also deeply suspicious of it, suspicious of the idea of putting a chemical into our water, which, by the way, water is just a chemical itself. H2O. Now, there are real risks from too much fluoride. That is called fluorosis, and it is what caused brown teeth in Colorado Springs. Fluorosis can also weaken bones and joints. And there are some suggestions that too much fluoride can cause neurotoxicity and lead to lower IQ or neurocognitive issues in children. More research is needed there. And this is why our kids should not eat toothpaste, even if it tastes like butter bubble fruit. And again, the levels in fluoridated water, those are fine. As a way to answer the doubters, the American Dental association puts out a free book called Fluoride Facts. This book first appeared in 1952 and it now stretches to 144 pages of questions and answers. It starts with what is fluoride? And then it goes through such zingers as does fluoride affect the function of the pineal gland? And does fluoride at the levels found in water fluoridation affect human reproduction or fertility? And why does opposition to community water fluoridation? Continue this book. It's an exemplary exercise in debunking, but it is also in some ways an old fashioned approach to doubters. What worked in 1952 to overcome skeptics arguments about the greater good, about the health of our kids, about how cheap fluoridation is compared to dental surgery. Those arguments are somewhat less persuasive these days. Indeed, opposition to fluoride, it's gaining steam. In May 2025, Utah became the first state to outright ban the fluoridation of water systems. Florida did the same soon after. Several other states and many communities are considering similar moves, goaded by the current leaders in the federal government. But here's the head scratcher. As common as fluoridation is In America, the US is actually an outlier worldwide. Less than 10% of the world's population consumes fluoridated water. Most European countries do not fluoridate their water supplies. So do they have much worse tooth decay? Well, in 2024, an independent team of scientific researchers attempted to answer that question. They conducted a systematic review of all the evidence on water fluoridation in high income countries, including the U.S. this was part of a Cochrane Collaboration, the most respected and most rigorous research group in the world. They found that water fluoridation may provide some slight benefits, but the effect was so small as to not be measurable. In fact, European countries that do not fluoridate their water had a similar rate of tooth decay as the US and other countries that do fluoridate. Now, the report did not question the benefit of fluoride. The question was whether adding fluoride to water systems is necessary today. Because the difference between 1950 and today is that fluoride, toothpaste and rinses are ubiquitous and widely used. So much so that adding fluoride to water it might be largely redundant. Now, this was a controversial finding. The ADA quickly issued a statement reiterating the organization's support for community water fluoridation. But are American dentists just stuck in the past? Is all that fluoride truly necessary? Well, it turns out that there is another difference between the US and all those non fluoridated European countries. Most of those countries have government funded health care, including dental care, meaning free and available. In the US health care is not provided by the government. And not only that, but dental care in the US is covered by a different kind of insurance than regular medical care. So where around 8% of Americans lack medical coverage, 27% of Americans lack dental coverage. As if our health stops somewhere between our jaws and our gums. And coverage is even worse among lower income people. And that trend, it's going the wrong way. Fewer children in the US get a dental visit every year. So water fluoridation may not be necessary for those who brush, floss and get a regular checkup. But for the many millions of Americans without access to dental care or without good habits or understanding of their dental health, fluoridation likely provides a whole lot of good. It helps to do another before after. Here, let's look at Juneau, Alaska and Calgary, Ontario, two North American cities that had fluoridated water but then removed it around 15 years ago. In both cities, cavities in children increased significantly after fluoride was removed. So Calgary, they added fluoride back to its water system in 2025. Juneau, on the other hand, has not. In Juneau, without fluoride, children under 6 years old are getting many more cavities, around 60% more fillings per child. Remember, even Dr. Machen grew up not going to the dentist and not really knowing about dental hygiene. And now as a dentist, she sees the benefits of good care every day.
Dr. Esther Machen (Dentist)
I've had such a rewarding experience being a dentist because I absolutely love teeth, which sounds weird, but I love working with people. And it's really cool to have a job that you can like fix something and have an immediate result, whether that's immediate pain relief or immediate cosmetic result. It's just very, very rewarding. I've had just some super valuable experiences when they've come back and they're doing so much better. And so you know that you've changed that child's life drastically just in the amount of pain and suffering that they'd have with their teeth. And you know, right now I'm restoring a 15 year old girl's teeth and her grandma came in and said, you know, she won't smile anymore. Half the teeth are gone in the front, eaten away with decay and they look horrible. And it's a rewarding experience because I can, you know, give massive discounts to get those things done so that then she can smile again. And she is smiling again.
Thomas Goetz (Host/Narrator)
It really goes back to what Simone and Linus said. If you brush your teeth with fluoride toothpaste twice a day and you go to the dentist twice a year, sure, you may not need fluoridated water. If your parents taught you how to brush and floss like Rachel did, then you are probably doing fine, whatever water your city supplies. And if you happen to live in a country with nationalized health insurance where dental care is free, your teeth are probably good. But if you can't afford dentists, if your parents didn't teach you how to brush and floss and forget to buy fluoride toothpaste. Well, you better hope your city fluoridates its water because otherwise you are pretty much living in the 1950s, far away from Grand Rapids or Colorado Springs. Get ready for sugar bugs and toothaches. They will be your constant companions. That's it for this drug story about fluoride, and this is the last episode of our first season of Drug Story. This has been so much fun and I'm excited to say that there will be a Season two. We've got some amazing stories to tell. Adderall and adhd, hormone replacement therapy, Humira and autoimmune diseases, and a dozen more. It's going to take a few months to make this next batch, but we will drop some surprises and updates into this feed along the way, so don't forget about us. For an annotated list of our sources for this episode, visit. Drugstory co Drug Story was created, recently, written and hosted by me, Thomas Goetz. Rachel Swaby is our producer and sound designer. Mark Bush is our engineer. Molly Warner is our research director. Drug Story was produced with support from the University of California, Berkeley School of Public Health. And thank you to our guests Simone and Linus, Dr. Chase Kleinstecker and Dr. Esther Machen. This episode of Drug Story can cause more frequent brushing, less craving for sweets, and remembering that you are probably overdue for a checkup, we recommend that you be honest with your dentist about how often you really floss, be more grateful for modern dentistry, and to be on the lookout for tooth worms.
Linus and Simone (children)
Can I add the headphones.
Drug Story Podcast – Episode Summary
Episode Title: On fluoride and tooth decay
Host: Thomas Goetz
Date: March 31, 2026
This episode explores the story of fluoride: its transformative impact on dental health, its classification as both a drug and a public health tool, and the scientific, historical, and social controversies surrounding its use. Using fluoride as a lens, host Thomas Goetz investigates the story of tooth decay (“caries”), the evolution of dentistry, and the modern debates about water fluoridation, highlighting the interplay of medicine, politics, and daily life.
“The bacteria that cause tooth decay are basically sugar bugs, and Linus is correct about how fluoride works.”
—Thomas Goetz, (02:21)
“You may not think of fluoride as a drug, but it fits the bill… Fluoride needs to be prescribed like any drug or medicine that can cause harm.”
—Thomas Goetz, (03:30)
“If you think that in the past there was some golden age of pleasure and plenty, let me say one single word: dentistry.”
—Thomas Goetz, quoting PJ O’Rourke, (18:36)
“In Grand Rapids, tooth decay among children dropped by more than 60%—nationwide, a similar trend played out over the decades.”
—Thomas Goetz, (29:23)
“Water fluoridation may not be necessary for those who brush, floss, and get a regular checkup. But for the many millions of Americans without access to dental care or without good habits…fluoridation likely provides a whole lot of good.”
—Thomas Goetz, (44:59)
“If I ranked modern dentistry on the list of humanity's most amazing achievements, it would be in the top 10, maybe the top three, ahead of the moon landing or television.”
—Thomas Goetz, (07:36)
“The world collapsed into a black pinhole inside their heads.”
—William Greenway, reading from his poem “Toothache,” (13:48)
“I watched my younger siblings start to suffer with severe tooth decay. I really attributed the tooth decay to no fluoride in the water. And that’s one of the things that drove me to go to dental school.”
—Dr. Esther Machen, (33:04)
Final Word:
“If you brush your teeth with fluoride toothpaste twice a day and you go to the dentist twice a year, sure, you may not need fluoridated water... But if you can’t afford dentists... forget to buy fluoride toothpaste... you better hope your city fluoridates its water, because otherwise you are pretty much living in the 1950s... Get ready for sugar bugs and toothaches. They will be your constant companions.”
—Thomas Goetz, (47:24)
For annotated sources and more information, visit Drug Story’s website.
Guests in This Episode:
This is the final episode of Season One of Drug Story. Season Two promises fresh explorations into Adderall, hormone replacement, Humira, and more.