Meryl Horn (Senior Producer, PhD)

So fluoride can sort of outcompete iodine. So in the past, we've actually given fluoride as a treatment for people who have overactive thyroids. And there was a study that found that people who lived in an area with fluoridated water were twice as likely to have hypothyroidism than people who didn't.

So fluoride can sort of outcompete iodine. So in the past, we've actually given fluoride as a treatment for people who have overactive thyroids. And there was a study that found that people who lived in an area with fluoridated water were twice as likely to have hypothyroidism than people who didn't.

But like other studies haven't found those associations or like one found that it was only significant if you also had an iodine deficiency to begin with. So what do we make of that as well? What do you make of it? Yeah, I mean, it's not like I looked at the evidence and was like, oh, this is real for sure. Like, fluoride is giving us all hypothyroidism.

But like other studies haven't found those associations or like one found that it was only significant if you also had an iodine deficiency to begin with. So what do we make of that as well? What do you make of it? Yeah, I mean, it's not like I looked at the evidence and was like, oh, this is real for sure. Like, fluoride is giving us all hypothyroidism.

And then for other stuff, it's even less convincing. Like, for bone health, there were some studies that say that drinking fluoridated water can increase your risk for bone fractures. But there was a meta-analysis that looked at everything together and said that there was no increased risk.

And then for other stuff, it's even less convincing. Like, for bone health, there were some studies that say that drinking fluoridated water can increase your risk for bone fractures. But there was a meta-analysis that looked at everything together and said that there was no increased risk.

But then, like, I don't know, for me, even if there are just a few studies saying that some of these risks could be real, it doesn't make me feel great because, like, I mean, the stakes are so high. We're doing this at such a big scale that ideally you'd want to see, like, a mountain of rock-solid evidence of studies all saying this is totally safe. For sure.

But then, like, I don't know, for me, even if there are just a few studies saying that some of these risks could be real, it doesn't make me feel great because, like, I mean, the stakes are so high. We're doing this at such a big scale that ideally you'd want to see, like, a mountain of rock-solid evidence of studies all saying this is totally safe. For sure.

This is okay to be basically forcing this many people to be having this chemical.

This is okay to be basically forcing this many people to be having this chemical.

And we don't have that. I talked to Ashley about why we don't have a more definitive consensus on this. I mean, why has it taken so long? Is this kind of a failure of science?

And we don't have that. I talked to Ashley about why we don't have a more definitive consensus on this. I mean, why has it taken so long? Is this kind of a failure of science?

Yeah, that seems true.

Yeah, that seems true.

Well, scientists all agree that back in the 1940s when we first started doing this, there was this huge benefit. But lots of people today are saying that things are different now. And like, I think it does kind of make sense because when we first started doing this, our teeth were way worse. Like we didn't go to the dentist as often.

Well, scientists all agree that back in the 1940s when we first started doing this, there was this huge benefit. But lots of people today are saying that things are different now. And like, I think it does kind of make sense because when we first started doing this, our teeth were way worse. Like we didn't go to the dentist as often.

We didn't get sealants or brush our teeth with fluoridated toothpaste. Right. So it's something like putting fluoride in the water had this big potential to make a huge difference because our teeth were so crappy. Right. Where now people say that like, well, we don't really need to be doing that anymore because we have all these other like, you know, tools in the toolbox to help our teeth.

We didn't get sealants or brush our teeth with fluoridated toothpaste. Right. So it's something like putting fluoride in the water had this big potential to make a huge difference because our teeth were so crappy. Right. Where now people say that like, well, we don't really need to be doing that anymore because we have all these other like, you know, tools in the toolbox to help our teeth.

Well, now we actually have like kind of a perfect opportunity to look at this because as cities are taking fluoride out of the water today, we can see like, okay, how much, like do the teeth actually get worse in places that do that? Right. And so that's what I wanted to talk about with Lindsay McLaren. She's a professor in community health sciences at the University of Calgary in Canada.

Well, now we actually have like kind of a perfect opportunity to look at this because as cities are taking fluoride out of the water today, we can see like, okay, how much, like do the teeth actually get worse in places that do that? Right. And so that's what I wanted to talk about with Lindsay McLaren. She's a professor in community health sciences at the University of Calgary in Canada.