Why We Need to Talk About Fluoridation
When Hardy Limeback’s research on bone tissue led him to the realization that public water fluoridation is a costly mistake, his colleagues urged him to keep quiet. Instead he called a meeting to apologize for misleading his dental students on the safety of fluoride, beginning a lifelong conversation about the negative health effects of artificial water fluoridation. Despite the toll on his career, Dr. Limeback continues to voice his concerns about this practice that affects millions of people around the world. In his interview with Melissa Gallico, he explains why—”I’m passionate. I want to see change before I die.”
Dr. Hardy Limeback is the former head of preventive dentistry at the University of Toronto and a past president of the Canadian Association for Dental Research. He also has a PhD in collagen biochemistry and is a coauthor of the U.S. National Research Council’s 2006 report, Fluoride in Drinking Water.
Listen to the podcast here: https://www.gallico.co/episode-1-hardy-limeback
READ THE TRANSCRIPT.
This podcast is produced by Gallico Studios, a multimedia effort supported by a community of activist like you who share the goal of ending artificial water fluoridation. To join the studio or learn more, visit our website at www.Gallico.co.
Welcome to The Gallico Show. I’m your host, Melissa Gallico, author of The Hidden Cause of Acne: How Toxic Water is Affecting Your Health and What You Can Do About It and F Is for Fluoride: A Feasible Fairytail for Freethinkers 15 and Up. I’m launching this podcast series because about 10 years ago I noticed something about life in America that we desperately need to start talking about. Here’s the backstory.
So I’ve always been fascinated by the study of science and technology. Not just the mechanics of it, but how science and technology influence society, which ideas take hold and why, and what is the effect of those decisions both an everyday lives and on a national and international scale. When it came time for me to choose an undergraduate field of studies in the 1990s, Georgetown University’s School of Foreign Service had the perfect major for me. They were the first school to offer a degree in the study of science, technology, and international affairs, a program called STIA. And that is the exact field I worked in throughout my subsequent career.
After graduation I was commissioned as an officer in the United States Navy. I served five years in the military before transitioning over to the Federal Bureau of Investigation where I worked in science and technology as an intelligence analyst. During my time at the FBI, I was selected for a Fulbright scholarship to earn a master’s degree at the University of St. Andrews in Scotland. This is where our story takes an unexpected turn because it was my time in Scotland that led me to a critical observation about my life in the United States.
This was not the first time I had lived overseas. During my career in national security, I studied abroad in Senegal and Tunisia, I was stationed in the Caribbean, and I spent many months on overseas deployment in the military. But living in Scotland made me realize something. Every time I lived overseas, the cystic acne that plagued me in the United States would effortlessly disappear. I was in my mid-thirties at this point but when I would return to the U.S., even for a brief visit, I would start to develop painful cystic breakouts around my mouth and jawline. When I moved back to Florida after living in Scotland for a year, my acne was the worst it had ever been. This is when I realized that my acne was caused by consuming fluoride added to the water supply.
Now, if you have preconceptions about fluoride—and most Americans do for reasons we’ll discuss later in this series—I fully recognized that the idea that fluoride causes acne can sound insane. Or maybe you think I’m mistaken or I’m confused or my acne was really caused by some other random explanation like hormones or histamines or who-knows-what. But let’s think about this for a minute. I’ve lived in this skin my whole life, I’m literally an intelligence analyst, and I’ve carefully studied this theory that fluoride causes acne for the last 10 years to the point where I’ve published a book about it and helped countless other people heal their chronic acne by learning how to avoid fluoride in their diet. You can read their testimonials and see before and after photos, mine included, on the website for my book, www.HiddenCauseofAcne.com.
Before I realized that fluoride was the cause of my acne, I had preconceptions about fluoride, too. I always assumed it was safe. I assumed it was good for me. I drank fluoridated water, brushed my teeth with fluoridated toothpaste, and religiously had fluoride treatment at the dentist twice per year. I don’t think I even heard about the controversy over fluoride until I was living in Scotland, a country where 97% of the general public opposes fluoridation.
I remember when I first learned where the fluoride added to water comes from. I called my boyfriend at the time, now my husband, and said, “Did you know the fluoride added to the water supply is actually fluorosilicic acid that comes directly from the smokestacks of phosphate fertilizer plants in Florida?” He didn’t believe me. But I told him, the information is right there on the CDC website. They call it a byproduct of fertilizer mining but it could also be accurately described as a highly toxic air pollutant.
When artificial water fluoridation was first proposed in the mid-twentieth century, fluoride was a leading airborne pollutant. A 1971 report by the U.S. Department of Agriculture states that airborne fluorides caused more damage to domestic animals than any other air pollutant. These corporate polluters were some of the most powerful companies in the world and they were the ones funding the research behind fluoride. They were also the ones funding the marketing efforts.
Careful study of the history and science behind public water fluoridation reveals it is not the great public health achievement the CDC currently claims it to be. If we are honest with ourselves, we have to admit that fluoridation is a pollution scandal—the biggest pollution scandal in American history—and we need to start having open and frank conversations about how this happened, how it is affecting our society, and most importantly, how we can correct this very costly mistake.
I want to conclude this introductory episode of The Gallico Show with a brief discussion with someone who has a lot of experience in these types of difficult conversations about fluoridation. My guest, Dr. Hardy Limeback, is a retired dentist, professor, and former head of preventive dentistry at the University of Toronto. He also has a PhD in collagen biochemistry and is a past president of the Canadian Association for Dental Research. In 2006, he served on the U.S. National Research Council committee on fluoride in drinking water.
Midway through his prolific career in dentistry, Dr. Limeback famously reversed his stance on public water fluoridation stating, “the evidence has convinced me that the benefits of water fluoridation no longer outweigh the risks.” Despite the heavy toll on his professional life, he continues to speak out about the dangers of fluoridation in the hope that he will see the day when this obsolete practice comes to an end.
Melissa Gallico: Dr. Limeback, welcome to the show. Was it difficult for you to publicly change your position on fluoridation?
Dr. Limeback: Thank you for interviewing me, Melissa. I’m glad to join your podcast. Yes, it was a difficult decision for me to change my mind on fluoridation because basically every dentist and every teacher in dentistry was promoting fluoridation in those days. I was doing some research on the effects of fluoride on teeth and bones and found that there was a detrimental effect, not only to the teeth but also to bones. And that’s when I changed my mind about fluoridation, that it wasn’t really as safe and effective as we all had thought.
Melissa Gallico: If you could think back to when you first started questioning the safety of artificial water fluoridation, what was the information that you found to be the most troubling at the time? Was there a certain study or a certain line of evidence that first give you pause about fluoride?
Dr. Limeback: Back in 1993, I published my first paper on fluoride looking at whether or not we are over exposed to fluoride in North America because of water fluoridation. There had been a few publications about fluoride accumulating in bones. We know from animal studies that the more fluoride that accumulates in bones, the more fragile they become. You can break bones more easily if it has too much fluoride in it. So we were concerned about that, and there were colleagues of mine who also felt the same way, especially those who were working on bone research and bone health thinking that maybe too much fluoride in the bone was detrimental to humans. We had no studies to show whether or not fluoride was hurting people’s bones except those studies in India and China where endemic fluorosis is common, which is basically an area where there’s too much fluoride in drinking water. India and China are very common areas where there’s too much fluoride exposure and they end up with bent bones and brittle bones and bone spurs and arthritis and all kinds of problems related to fluoride in the bones. So we’re concerned about that in North America and that’s why I started to do that research. I started back in 1993.
Melissa Gallico: So you became interested in the effects of fluoride because of your research in collagen biochemistry which we’ll talk about in an upcoming episode in this series. What would you say was the evidence that ultimately compelled you to oppose fluoridation publicly as a dental treatment?
Dr. Limeback: Initially it was my observations in my own clinic. When I stopped doing research on elderly people in nursing homes, I opened up my own dental office and started seeing kids with white spots on their teeth and I thought, “well this is strange. Why are there so many kids with white spots on their teeth?” Some kids even with some brown stains. And that was a classical pattern of dental fluorosis. Why are these kids getting so much fluoride in their teeth during tooth development? So I started to think about where all the sources of fluoride were coming from. Mostly where I was practicing in Mississauga which is a bedroom community of Toronto, Canada, I was seeing a lot of fluorosis and started to do some research in the dental fluorosis area. I discovered that there was way too much dental fluorosis, not only in Canada where there is fluoridated cities, but in my practice. So I had to start treating these kids with fluorosis and it’s quite expensive for families to handle, to try and treat the fluorosis which most kids find objectionable and they want to treat it because they don’t want to be embarrassed with stained teeth.
Melissa Gallico: It’s interesting that dental fluorosis was one of the first indicators to you because I also have dental fluorosis and that was one of the first signs that I was getting too much fluoride as a child. My parents noticed the discoloration on my teeth and they asked the pediatrician but they didn’t get an answer. They didn’t know that it was because of the fluoride supplements that my dentist was prescribing for me. We were on well water and the dentist assumed that I needed more fluoride in my diet so I took these pills and my parents were never told to look out for dental fluorosis.
Dr. Limeback: It’s true. Back in those days there wasn’t nearly as much knowledge about dental fluorosis as there is today. Back in those days they just thought it was intrinsic staining of some kind but now of course every dentist knows what they’re looking at, or should know what they’re looking at, in terms of white spots. It’s called hypocalcification, or poor mineralisation of the teeth. Those white spots are indicative of too much fluoride accumulation during tooth development and it’s very common. Now it has increased to the point where fifty percent of children are getting some kind of dental fluorosis. And the more severe kind that needs to be treated with fillings or veneers, porcelain veneers, that proportion of kids has gone up from one in every eighth kid to almost one and every third kid. So it’s quite a serious problem in North America, too much fluoride exposure.
Melissa Gallico: So you’re seeing all of these children come into your practice with dental fluorosis. And in an account of a meeting that you had with your colleagues and students at the University of Toronto where you first expressed proposition to public fluoridation, you apologized for misleading them on the safety of fluoridation even though it was clearly unintentional. You’re quoted as saying, “For the past 15 years, I had refused to study the toxicology information that is readily available to anyone. Poisoning our children was the furthest thing from my mind.” Why do you feel that you and so many dentists even today were able to ignore the derogatory science on fluoride for so long even though you were seeing evidence of it on children’s teeth?
Dr. Limeback: If you’re not looking at the fluoride toxicity literature, you basically buy the rhetoric from public health saying that fluoride is safe and effective. As a researcher, when I discovered that there were side effects of fluoride in the human body it was basically my duty to look into whether or not this claim of “safe and effective” is something that I should continue teaching. I remember clearly the day that I spoke to the student body about my mistake that I had made because I had never looked into the toxicology of fluoride when I was teaching preventive dentistry. I just assumed that putting fluoride on kids teeth was safe because I was told that. I just assumed that drinking fluoridated water was safe because I was told that. I was told that as a dentist and as a dental student. I was told that by the Ontario Dental Association, the Canadian Dental Association, the American Dental Association, all these organizations that actually don’t do research but basically fall along with what everyone else is saying, that fluoride is safe and effective. So after I discovered that it really wasn’t safe, I felt that I had to apologize to the student body and say, “Let’s take a look at the side effects and decide whether or not it is still necessary to put fluoride in the drinking water.” And another issue that really bothered me at the time was that I had assumed all those years that they were putting pharmaceutical-grade fluoride in the drinking water because it’s a drug. They were putting a drug in the drinking water. It turns out it wasn’t pharmaceutical-grade fluoride at all. It was a side product of the phosphate fertilizer industry. I was horrified when I heard about that and I started doing more research into that area. So that’s really what got me turned around
Melissa Gallico: Do you think most dentist know where the fluoride added to water comes from? Do you think they assume it’s a pharmaceutical grade fluoride or did they know that it’s fluorosilicic acid directly from the smokestacks of the phosphate fertilizer plants?
Dr. Limeback: I’m sure that most dentists when they find out about the source of the fluoride might question why they still promote fluoridation if there is any evidence that the side product is worse than a pharmaceutical grade product. And we know it is worse because it’s never been tested for safety and it contains contaminants that are known carcinogens. It contains arsenic. They say that the amount of arsenic that we are adding to the drinking water is still far below what is allowed in the drinking water but that, to me, is irrelevant. You shouldn’t be purposely adding a known carcinogen to the drinking water just to try to save maybe one or two teeth per lifetime of fluoridation. It made no sense to me. And the more I looked into it, the more I became quite annoyed that the public health people promoting fluoridation, the scientists, the dentists who promote fluoridation, refuse to look at the literature showing that there was obviously some problems with using this chemical in drinking water.
Melissa Gallico: What would you say to dentists or other health officials who are in the position you were and 25 to 30 years ago when you were doing your job advocating for the use of fluoride to prevent cavities and unaware of the extent of the toxicology studies and other research that concerns you so much today?
Dr. Limeback: I would say, please read the literature if you have the time. I know dentists are so busy just trying to make a living, just trying to keep their head above water, I know I did. I had problems maintaining my practice on a couple of days a week maximum. It’s really hard to keep a practice going, so they are busy. They don’t want to look into the literature and they are basically being told by their profession, their dental association, what to promote. In fact they’re being told in the States by the American Dental Association that it’s their duty to promote water fluoridation. It makes no sense. Once they start reading about the harmful effects of fluoridation and they see the fluorosis on the kids themselves, then they start to think about whether or not maybe they shouldn’t be putting fluoride in their own drinking water at home. You’ll be very surprised when you start asking dentists what they do at home themselves. They filter their drinking water. They don’t want their kids to have that much fluoride.
Melissa Gallico: I know this is a sensitive question so feel free to provide as little or as much information as you care to share, but how did your opposition to public water fluoridation affect your career and your life in general?
Dr. Limeback: It turned my life upside down. When I was doing research on enamel proteins and tooth development, I was happy in my lab. I had grants. I was well-funded from the federal government looking at tooth development and the proteins that were responsible for proper tooth development. When I started getting interested in fluoride research, then I discovered that, “wait a second, fluoride is interfering with all of this.” It’s causing dental fluorosis. It’s accumulating in our bones. It’s changing our bone architecture and strength. Why are we ingesting fluoride just to try and save a couple of fillings per kid? So I started doing some research in that area and as I told you, back in 1999, it was a time when I became vocal about my opposition to water fluoridation simply because of the effects on teeth and bones. That’s when my career actually headed downhill. Even though we received some grants to look at the effects of water fluoridation on bone and I did some of my own unfunded research on dental fluorosis, it didn’t take very long before I lost my lab and ended up doing more teaching and less research. And I discovered that my profession was not supportive of me at all. They were quite annoyed at me because it was disturbing the balance that they were used to in the profession. The dentists were basically in control telling patients what to do. And quite a few patients, after it became known publicly that fluoride might actually have some side effects, decided that they didn’t want it for their kids. And of course that is the first thing that dentists get upset about. It’s when patients tell the dentist that they are not interested in having a treatment. The dentists say, “well I know better than you do. You don’t know anything.” But a lot of people have actually become more educated using the internet as a way to educate themselves, and not just crazy conspiracy theory websites, they are looking at the literature. They are actually reading papers. Some patients know more about fluoride than the average dentist. So that’s basically why the dentists are very upset about the public arming themselves with the knowledge that fluoride might be harmful. They just don’t like the fact that they are being told that they don’t want a treatment that doesn’t do any good for them anymore.
Melissa Gallico: You mention losing your lab and losing the ability to continue your research. Was that a direct result of your public opposition to fluoridation?
Dr. Limeback: Yes, my public opposition was probably the reason that I lost the ability to do research. On the other hand it also allowed me to take part in the National Academy of Sciences fluoride in drinking water committee. They wanted a balanced committee. They didn’t want a committee of people who are pro-fluoridation. That’s basically what the National Academy of Sciences does quite frequently. They get together a panel of people of opposing views and I was clearly by that time (2003) opposed to water fluoridation which is the reason I was invited to take part in the review. So there were some benefits of being opposed to water fluoridation—I did serve on the National Academy of Sciences fluoride in drinking water committee—but the negative effects were basically, for me, devastating. It was career destroying. And I decided to retire early because of the lack of support that I received from my faculty and my friends, my colleagues, dental researchers, and the dental profession in general. I felt that I was an outlier and no longer welcome so I decided to retire early. It wasn’t that I was forced out or fired but my tenure was at risk and my license was at risk because of a complaint against me basically claiming that I was misleading the public. And I think that was really quite unfair of the profession to come down hard on me, but I survived all that and decided that taking early retirement and working from behind the scenes was probably the best thing I could do.
Melissa Gallico: So just to clarify, this wasn’t a complaint from a patient. This was a complaint from a pro-fluoride dentist. Is that correct?
Dr. Limeback: Yes, it was complaint from a public health dentist—a public health dentist who was actually a friend of mine before that.
Melissa Gallico: That must have been really difficult. Do you ever regret your decision to oppose fluoridation?
Dr. Limeback: Oh, all the time. Looking back on my career, I was actually advised by a very well-known dental fluorosis researcher, basically she said, “Hardy, don’t talk about it publicly. Just stick to your lab research and continue to do your research but don’t criticize what’s going on publicly because it’ll just cause so much trouble that you may not survive it.” And she was absolutely right. I should have just kept my head down in my lab, done my research, published papers, and not do any television interviews or take part in any debates or toxicity councils. But I felt it was important for the public to know. I didn’t really want to sit in my lab and publish papers that the public would never read. I think the city councils who are responsible for putting fluoride in the drinking water, they had to know.
Melissa Gallico: I find it interesting how your story parallels that of John Colquhoun, the former principal dental officer In Auckland, New Zealand. For listeners who don’t know his story, Dr. Colquhoun was the chairman of New Zealand’s fluoridation promotion committee when he came to the determination that the evidence supporting fluoride’s ability to reduce cavities was not as strong as he previously believed and that the dangers outweigh any potential benefits. In 1997, he published an article in a journal from Johns Hopkins University called Perspectives in Biology and Medicine explaining why he changed his mind about fluoridation. Were you aware of Dr. Colquhoun’s decision beforehand and if so, did you ever reach out to him about it?
Dr. Limeback: No, I didn’t really get to meet him. I knew of him when I became vocal about fluoridation. When I was publicly outed, basically, by the media about my position against water fluoridation, then of course I got to know all the other scientists who have tried to point out the negative effects of fluoridation. That’s when I found out about John from down under. I really didn’t know many of the other researchers who were looking into the “safe and effective” claim and coming up with research that said it may not be as safe as we thought. And maybe it’s not as effective as we thought. I was getting to know them more as I became one of them on the other side of the fence, trying to look at the side effects of fluoride.
Melissa Gallico: In his essay on why he changed his mind about fluoridation, Dr. Colquhoun notes that he graduated with a degree in history, specifically the history of science, which he suggests might partly explain his reexamination of fluoride ahead of many of his colleagues. Is there something similar in your background that you think might have made you more open to the idea of questioning fluoridation?
Dr. Limeback: That’s a good question because when I became publicly vocal about fluoridation possibly causing harm, I certainly stood out in the dental profession. Every dentist was saying that fluoride was so good for kids’ teeth, it saves kids’ teeth, it decreases the disparities between the poor and rich in terms of their dental health, and all the claims that were being made, it really kind of turned me around to look at the side effects and the harm that it might be doing. So yes, I changed my mind and I couldn’t leave that science alone. I had to investigate further.
Melissa Gallico: In my career in national security and intelligence, I’ve learned that traveling and submerging myself in other countries and in other cultures is a powerful way to increase my understanding of my own culture. Artificial water fluoridation is clearly a U.S. invention. Do you think it is easier for dentist like yourself, outside the United States, to question it and see past these long-standing claims that fluoride is safe and effective?
Dr. Limeback: I don’t know why the English-speaking countries are so adamant that water fluoridation is good for people around the world. The rest of the world does not agree. If you look at Europe, Japan, China, and much pretty all of the rest of the world, we are in a very small minority when it comes to the total number of people on this planet who think that adding toxic waste to the drinking water is a smart thing to do. Europeans were smarter 30 or 40 years ago when some of the dental groups tried to promote fluoridation (it’s usually the dental group that try to promote it) they were smart and they said, “well, we know that fluoride is an enzyme toxin. Why are we putting it in the drinking water? There’s no need for it.” So most of the cities in Europe that were fluoridating looked at the literature and said this is not something we need to do, and they stopped it. In fact, some places even banned it. And in India and China and places that have dental fluorosis and endemic skeletal fluorosis, they know it’s harmful so they never even bothered to start.
Melissa Gallico: What concerns you most about public water fluoridation today?
Dr. Limeback: What bothers me today is that the side effects are obvious to everybody, and yet they still consider fluoride one of the best public health measures of the twentieth century. It is now going to be one of the worst public health moves of the 21st century unless they stop fluoridating. People will look back on the 21st century and think, “whoa, they didn’t stop fluoridation. What a mistake that was.” We are now learning that fluoride has so many side effects, and it’s actually harming newborn children. Not just dental fluorosis but also the thyroid gland and the brain, in terms of the development of the brain. We are now seeing that it may actually lower IQ. It may affect thyroid function and the endocrine system. There are so many side effects now. Back when I first worried about bone and teeth, I thought, “okay, bone and teeth. We can maybe have a little bit of flouride buildup in our bone and teeth and it’s not a big deal as long as the fluorosis is mild.” But it actually is worse now than it was back in the days when they said, “we need a little bit of fluoride and let’s try and not get too much dental fluorosis.” Now it’s rampant. Dental fluorosis is rampant. We are getting fluoride from way too many places. We’re getting it from the drinking water. We’re getting it from pollution. We’re getting it from tooth products, oral care products, toothpaste, mouthwash. We’re getting it from food, from tea, from all kinds of sources. Kids are getting way too much fluoride.
Melissa Gallico: Pesticides are another one that I like to throw out there because people don’t realize that fluoride is a common pesticide used in California, especially on grape products, so grape juice and certain wines. Europeans were the first ones to measure these high amounts of fluoride in the wine that they were importing from California.
Dr. Limeback: Yeah, of course when the anti-fluoridationists complain about putting rat poison or pesticide in the drinking water, then of course they are labeled as conspiracy theorists and radicals. But when you look at how much fluoride actually accumulates in the body throughout the lifetime, we don’t need to put it in the drinking water. We don’t need to consume it. Actually ingesting fluoride does nothing to prevent dental decay. It works topically. It works by basically loading up a little fluoride into the dental plaque and that’s how it works. There’s no reason to ingest it or swallow it.
Melissa Gallico: Dr. Limeback, thank you so much for agreeing to be on this podcast, and for everything you’ve done to speak out about fluoridation, and to have these conversations even when I’m sure there are very difficult for you. I want to leave you with one last question. You worked in dentistry for almost 40 years and as you mentioned, you retired way too early in your opinion. Now you live in a beautiful part of the world with a loving family, and yet I see you on Twitter almost everyday tweeting about fluoride, trying to get the attention of professional organizations like the Arthritis Foundation, government officials, journalists, celebrities, all in an attempt to warn your fellow citizens about the dangers of fluoride. Why do you continue to speak out about fluoridation even today on this podcast?
Dr. Limeback: Well, my wife wonders that same thing. She says, “you’re retired now, why are you still doing this?” Basically, I’m passionate. I want to see change before I die. I’m not sure this is going to happen in my lifetime. Fluoride has been around since 1945. It’s a 73-year experiment. They still don’t know what they’re doing. They still don’t know how it affects human beings. Not one single drug trial to actually prove that it’s effective. The actual benefit is so small that if you look at it now, it’s maybe one filling or one tooth saved from dental decay after a lifetime of fluoridation. Because we are being exposed to so many other sources of fluoride, especially toothpaste. Toothpaste can do it all. You don’t need to put fluoride in the drinking water. And why I’m still on Twitter, why I’m still pushing this public awareness of fluoride in the drinking water, is because we need to make change in North America. Kids are being affected by this policy. This is now outdated policy that should not be in effect anymore. Europe has stopped it. The rest of the world is smarter than us. We continue to listen to the dentists and they don’t know anything about toxicity of fluoride. It makes no sense.
If you enjoyed this premiere episode of The Gallico Show, please subscribe and leave a review. It really helps other listeners find the show. The rest of the series will be released in early 2019 and I’m working on some exciting interviews with the leading voices opposed to fluoridation, including past president of the EPA Union Dr. Bill Hirzy, founder of the International Academy of Oral Medicine and Toxicology (IAOMT) Dr. David Kennedy, and water activist and anti-pollution icon Erin Brockovich. To sign our petition to end fluoridation, visit Petition.Projectfree.Me. To find out how you can become a member of Gallico Studios and support this podcast, visit our website at www.Gallico.co. Thanks for listening.
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*Original article online at https://www.gallico.co/episode-1-hardy-limeback