Are we sure about fluoride?

Summary

Unexplainable Podcast Summary: "Are We Sure About Fluoride?"

Episode Title: Are We Sure About Fluoride?
Host/Author: Vox
Release Date: May 21, 2025

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1. Introduction to Emily Oster and "Expecting Better"

The episode opens with Noam Hassenfeld introducing Emily Oster, a renowned health economist and author best known for her bestseller, Expecting Better. Oster's interest in demystifying health guidelines began during her own pregnancy when she questioned the myriad restrictions recommended by her doctors.

Noam Hassenfeld [01:05]: "If you've heard the name Emily Oster, it's probably because you or someone you know is having a baby."

Emily Oster [03:06]: "You know, we can tell people a number, and then we need to help them understand the number."

Oster's approach emphasizes understanding the underlying evidence behind health recommendations, advocating for informed decision-making rather than unquestioning adherence to conventional wisdom.

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2. The Fluoride Debate: History and Current Concerns

As Oster's expertise grew, she began receiving increasing inquiries about the safety and efficacy of fluoride in drinking water. This concern has intensified, with some states like Florida moving to ban fluoride, reflecting a growing public skepticism.

Emily Oster [03:24]: "Growing questions about whether fluoride in drinking water is doing more harm than good."

Oster highlights the polarized nature of the fluoride debate, where misinformation and extreme viewpoints often overshadow scientific discourse.

Emily Oster [04:19]: "Fluoride has been subject to a public health smear campaign and mass hysteria."

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3. Research Findings on Fluoride Benefits and Risks

Oster delves into the historical and scientific background of water fluoridation, tracing its origins to early 20th-century dental studies that linked fluoride to reduced tooth decay. She acknowledges the unequivocal benefits of fluoride in preventing cavities but also addresses concerns regarding potential neurodevelopmental impacts at high exposure levels.

Emily Oster [08:58]: "The studies from which we conclude that almost exclusively come from places where there are very high levels of fluoride naturally occurring in the water."

Oster synthesizes a range of studies, concluding that while high levels of fluoride can negatively affect IQ and neurodevelopment in children, the low levels used in U.S. municipal water systems are generally safe and beneficial for dental health.

Emily Oster [10:08]: "It's, you know, a half a point of IQ per unit of fluoride. At these higher levels, it's a little bit of a hard number to look at, but I guess what I would say is, like, small but significant impact."

She emphasizes the importance of dose, asserting that "the dose makes the poison," with low levels providing dental benefits without the associated neurological risks observed at higher concentrations.

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4. The Role of RFK Jr. and Conspiracy Theories

The conversation shifts to the influence of Robert F. Kennedy Jr. (RFK Jr.), a prominent figure voicing anti-fluoride sentiments and other conspiracy theories. His status as head of America's health and science agencies lends undue credibility to fringe science, complicating public health efforts.

Noam Hassenfeld [18:52]: "This is the guy behind the renewed push to get fluoride out of the water... He's the same guy who's promoted all kinds of conspiracy theories."

RFK Jr.'s baseless claims, such as linking fluoride to control over behavior or denying the HIV-AIDS connection, have fueled public distrust in established scientific consensus.

RFK Jr. [19:17]: "They're putting in 5G to harvest our data and control our behavior."

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5. Public Health Communication Challenges

Oster critiques the current state of public health communication, particularly the tendency to dismiss concerns as conspiracies rather than addressing the underlying questions. She advocates for transparency and nuanced dialogue to rebuild trust and empower individuals to make informed decisions.

Emily Oster [20:01]: "I think that's a mistake in the way that we communicate... It pushes them away on topics where we really should be communicating."

Oster argues that public health authorities often fail to "meet people where they are," relying instead on top-down directives that alienate those seeking understanding.

Emily Oster [21:13]: "It exactly right. And if you are so dogmatic and you never allow for the possibility any information is counter to what you're saying, then as soon as someone sees some piece of information like that, you're going to lose them."

She emphasizes the need for honest communication about uncertainties and encourages engaging with the public's specific questions to foster a more informed and trusting relationship.

Emily Oster [28:13]: "I would advocate a strategy of honesty... Ask people what their questions are and then try to engage those questions directly rather than assuming... what their questions are."

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6. Conclusions and Future Directions

The episode concludes on a note of cautious optimism. Oster expresses hope that future administrations can learn from past communication missteps to better handle public health messaging, balancing certainty and transparency to restore trust.

Emily Oster [29:24]: "I'm not very hopeful. Sorry... The truth is that, like, I was very frustrated during the pandemic with the messaging of the sort of public health officials."

Despite current challenges, Oster remains committed to promoting evidence-based discussions and empowering individuals to navigate health decisions with clarity and confidence.

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Key Takeaways

• Fluoride in Water: Proven to reduce tooth decay effectively at low concentrations, with minimal risks. High levels, however, may impact neurodevelopment.

• Public Health Communication: Transparency and addressing public concerns directly are crucial for maintaining trust and combating misinformation.

• Role of Influencers: Figures like RFK Jr. can significantly influence public perception, often spreading unfounded theories that undermine scientific consensus.

• Empowered Decision-Making: Encouraging informed choices based on evidence can lead to better health outcomes and increased public trust in health recommendations.

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For more insights and detailed discussions on scientific mysteries and public health debates, tune into the Unexplainable podcast by Vox, released every Monday and Wednesday.

Transcript

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[Noam Hassenfeld]

If you've heard the name Emily Oster, it's probably because you or someone you know is having a baby.

[Emily Oster]

Yeah, so I started writing about pregnancy when I got pregnant with my first kid, who is now 14.

[Noam Hassenfeld]

And when she started talking to her doctors, she immediately heard about all the things she couldn't have.

[Emily Oster]

You can't have hot dogs. You can't have deli meats. You can't have sushi. You can't have coffee, can't have alcohol.

[Noam Hassenfeld]

There was a lot of can't, but not a lot of why. So Emily asked her doctors, what exactly was the risk she was avoiding? Like, how strong was the evidence?

[Emily Oster]

Like, okay, if I avoided ham, how much would that change my risk of listeria? Like, how much do we really know and how large is any given risk?

[Noam Hassenfeld]

Emily thought these were pretty basic questions, and she was kind of shocked when her doctors just didn't have the answers. Emily's a health economist at Brown, so in order to get the kind of answers she was looking for, she decided to go straight to her comfort zone. The actual studies. Some of what she found lined up with conventional wisdom. Like cigarettes. Definitely bad, but a lot of it wasn't as black and white as she'd been told. The data said a ham sandwich every once in a while wasn't so bad. Neither was a cup of coffee. But then some things that seemed helpful, like bed rest. Way riskier than you might think. And then when her friends started getting pregnant, they started coming to her for advice. So much that she decided to write a Book. It's called Expecting Better, and it was an instant bestseller. There were clearly lots of people out there who wanted something like this. At the same time, the book was kind of controversial. It went against lots of conventional wisdom about what pregnant people should or shouldn't do. Some people thought Emily was being a little cavalier. But Emily just saw herself as laying out the evidence. She didn't want to tell people what to do. Her point was that pregnant people shouldn't be talked down to, that they can handle the data and they can make their own decisions.

[Emily Oster]

You know, we can tell people a number, and then we need to help them understand the number. For me, that's sort of one of my ways into a lot of these questions.

[Noam Hassenfeld]

Over the years, Emily's kept getting questions from parents, and recently she's been hearing a lot about one particular concern tonight.

[Emily Oster]

Growing questions about whether fluoride in drinking water is doing more harm than good.

[Noam Hassenfeld]

The incoming administration will advise all US.

[Emily Oster]

Water systems to stop adding fluoride to their water supplies. Florida is set to become the second state in the nation to ban fluoride in water. A couple of years ago, this started surfacing more and more frequently. And the questions people were asking me, you know, I'm hearing fluoride is dangerous. How do I understand this? And so I've sort of kept updating my writing on this as it has become obviously now a very big topic of discussion. Very exciting. Everyone is an expert on water. Fluoride. Worse, I just found out there's literally hydrogen in our water. Yeah, we're drinking this.

[Noam Hassenfeld]

This is why I wanted to talk to Emily, because most of what I've been hearing about fluoride has sounded pretty extreme. On one side, you've got the fluoride haters. Fluoride science is completely made up.

[Emily Oster]

It's literally insane.

[Noam Hassenfeld]

Allowed to stand because our governments are completely corrupt. You do not need fluoride treatments.

[Emily Oster]

They are poison.

[Noam Hassenfeld]

On the other side, you got the people that think the haters are just ridiculous.

[Emily Oster]

Fluoride has been subject to a public health smear campaign and mass hysteria.

[Noam Hassenfeld]

This conspiracy started in the 40s because people thought they were putting fluoride in.

[Emily Oster]

The water to turn us all into communists.

[Sponsor Announcement]

So, no.

Water fluoridation in the US does not make you dumber.

[Noam Hassenfeld]

On either side of this fluoride debate, you have people just yelling at each.

[Emily Oster]

Other with complete certainty, dude, it's like, that's not helping.

[Noam Hassenfeld]

And then there's Emily.

[Emily Oster]

I fundamentally believe that people are smart enough to work through understanding evidence. And the thing we're doing now is not working.

[Noam Hassenfeld]

I'm Noam Hassenfeld. And today on the bitter struggle over an unassuming chemical. How can we get on the same page about fluoride? In 1901, a dentist in Colorado noticed this strange brown stain on a bunch of his patients teeth. Over time, he realized their teeth weren't just stained, they were healthier. People with these weird stains had way less tooth decay. They even had fewer missing teeth. Eventually, scientists realized this was happening because this part of Colorado had unusually high levels of fluoride in the water. They realized that high levels of fluoride stained teeth. But they wondered whether lower levels might still help with tooth decay. So they did an experiment.

[Historical Narrator]

This is Grand Rapids, Michigan, a town becoming widely known to dentists and municipal authorities for its fight against tooth decay.

[Noam Hassenfeld]

It started in the 40s when officials added just a bit of fluoride to the water. Way less than what was in the water in Colorado.

[Historical Narrator]

Only excessive amounts of fluoride and can cause mottling of teeth.

[Noam Hassenfeld]

And then they waited.

[Historical Narrator]

After six years of fluoridation, the study shows that the six year old children who drank the water from birth had 65% less tooth decay.

[Noam Hassenfeld]

Pretty soon, other cities were getting their own experiments.

[Historical Narrator]

Studies in Newburgh, New York, Sheboygan, Wisconsin, Marshall, Texas and other cities show substantially the same results as those obtained at Grand Rapids.

[Noam Hassenfeld]

Within a few years, the difference started to become pretty clear.

[Historical Narrator]

Something has happened to the teeth of young children. Something that today is almost a dental miracle. Children's teeth just don't have as many cavities anymore.

[Noam Hassenfeld]

When Emily started reading and writing about fluoride, she started hearing stories like this from her family.

[Emily Oster]

My aunt wrote to me and was like, I know fluoride is important for teeth because my teeth are terrible and your father's teeth are even worse. But my kids teeth are great. And so, you know, at some point between when my father was a kid and when I was a kid, they started adding fluoride to the water.

[Noam Hassenfeld]

Emily's family tooth stories were a couple of interesting data points, sure, but obviously not enough to prove that adding fluoride to water is worth it or that it doesn't come with downsides. So she read every study she could find, all to get at this. Has fluoride actually been good for us? And just how good?

[Emily Oster]

So there is a lot of evidence of the impact of fluoride on tooth decay, like fluoride treatments. So that's like a thing you can randomize access to. And there is also some evidence from early municipal water fluoride introduction that introducing fluoride reduced the risk of cavities in kids. There is also some evidence on the flip side. So Israel pulled fluoride out of the water, and there is a little bit of evidence from there suggesting that the rate of cavities went up over time.

[Noam Hassenfeld]

Okay.

[Emily Oster]

I think what we don't have is something where we could be like, this is exactly the size of the impact there would be if we pull fluoride out of water. But there's also a huge amount of evidence that, like, fluoride is good for teeth.

[Noam Hassenfeld]

So we know fluoride is good for our teeth, prevents tooth decay. What do we know about the downsides?

[Emily Oster]

So at high dose levels, fluoride can be problematic for developing brains for kids or for exposure during pregnancy.

[Noam Hassenfeld]

Okay.

[Emily Oster]

The studies from which we conclude that almost exclusively come from places where there are very high levels of fluoride naturally occurring in the water. Like, there are areas of China and India in particular, where the groundwater supplies have very high levels of fluoride. You know, maybe five or six times as high as what you would see in a municipal water system in the US and there you see that, you know, Moving from, like 4 fluoride units to 5 does seem like it may have some small negative impacts on development in kids. And so that's kind of the piece of evidence that makes people concerned about fluoride, that at these higher levels, it has these impacts on basically on IQ and other neurodevelopmental metrics.

[Noam Hassenfeld]

If I'm being honest, when I first read about Emily taking fluoride concerns seriously, I was a little surprised. Like, most of the things I'd read were pretty quick to just say fluoride good. All those potential downsides are just a conspiracy, which is not at all what Emily was saying. Yeah. Do we have any idea of how big an impact it has on iq?

[Emily Oster]

It's, you know, a half a point of IQ per unit of fluoride. At these higher levels, it's a little bit of a hard number to look at, but I guess what I would say is, like, small but significant impact.

[Noam Hassenfeld]

But still an impact.

[Emily Oster]

But still an impact. Absolutely. Small, but still an impact.

[Noam Hassenfeld]

So is that to say that at low levels of fluoride in the water we notice no harmful effects and then at high levels we start to see some effects?

[Emily Oster]

Yeah. So that's basically, if you sort of take all of these studies together, of which I wanna be clear, there are many. So there are many, many studies of the relationship between fluoride and iq, some of which are run in places with very high fluoride, some of which are run in places with very low fluoride. If you kind of aggregate those and sort of take like a meta analysis which takes all of those together and you organize them, it is the dose that makes the poison. But at lower levels, you are not seeing those negative effects while you are getting these positive effects on teeth.

[Noam Hassenfeld]

When I was doing some background research for this episode, I did find a few studies that seemed to disagree with Emily that showed fluoride could have negative effects even at low levels. Like the levels in American water systems.

[Emily Oster]

Yeah. So it's like a very tricky space because there are many, many studies. Many of them are very small. None of them are like the gold standard randomized control trial study.

[Noam Hassenfeld]

Emily says there are some specific issues with these studies. Like, for one thing, a lot of them measured the fluoride levels in people's urine, which is a problem because those levels can be impacted by someone's general diet, not just how much fluoride they're getting from the water.

[Emily Oster]

And then on top of that, you have the issue that, you know, there's 40 studies of something, and people would be like, but what about this one study? You're like, yeah, that's what statistics are like. There's a distribution of effects.

[Noam Hassenfeld]

There's still some scientific debate on this, but when Emily looks at the big picture, of all the studies out there, the vast majority show that low levels of fluoride are safe.

[Emily Oster]

I mean, I think that the basic message is that municipal water levels in the US do not have fluoride at levels you would be concerned about.

[Noam Hassenfeld]

There are a few places in the US where fluoride levels do seem to be too high. But according to recent numbers from the CDC, that applies to just 0.01% of the population.

[Emily Oster]

When you look at large scale testing data, it does not look like we are seeing a lot of places that are at higher levels.

[Noam Hassenfeld]

So when parents have come to Emily with questions about fluoride in the water and they're pushing for an answer, she basically just tells them, you should just.

[Emily Oster]

Consume the water and not think about this question anymore.

[Noam Hassenfeld]

Other people have landed in a different place. Even if there are issues with those smaller studies, they say they're worth paying attention to. And Emily gets that not everyone is going to agree on this. Even if they look at the same exact data, It's a similar place to where she lands. In her book on pregnancy, she writes about friends who read the same data she did, and still decided to give up coffee. Even if Emily didn't think a cup of coffee was worth worrying about. Some people might just have a really low tolerance for risk. They might think any amount of uncertainty is too much.

[Emily Oster]

It's not crazy to say I'm worried about levels of fluoride, because at some level you should be worried. But I try to be sort of careful in this information to sort of say, like, there's absolutely nothing that should make you concerned about neurodevelopmental effects of the water fluoride that you see. Does that mean that some people will not choose to, like, drink a lot of bottled water or drink some other alternative? No. And really, the way we need to communicate that is to help people understand. Yes. You know, here's why that concern is coming up, but here's why it may not be relevant to the situation you're in. One of the things I say all the time is, like, no option is completely safe, you know, So I don't want you to come to me and say, like, you know, I'm not going to drink the water with fluoride. So my new plan is to go to this, like, stream out in the mountains and get my water from there. It's like, you know, that's got parasites in it. Like, that's got, like, giardia. Like, you're going to be very sick if you use that, and that's actually much worse. And so just making sure that, you know, people have thought about the potential downsides of the alternative.

[Noam Hassenfeld]

Also, maybe you're going to get in a car crash on the way to the stream.

[Emily Oster]

Yeah, I think the stream itself is much more risky.

[Noam Hassenfeld]

Yeah.

[Emily Oster]

Don't drink out of the stream.

[Noam Hassenfeld]

Right. Okay. That's the message for the episode. Do not drink out of the stream.

[Emily Oster]

Animals pooped in that.

[Noam Hassenfeld]

It's not just fluoride, though. It can feel hard to talk about all kinds of things in public health right now. So what can we do to get back on the same page? Emily's got some ideas in a minute. Support for the show comes from Koala. If you're hosting someone for a few nights, it can be stressful. You might pull your air mattress out from under the couch, plug it in, wait for it to fill up, get on top of it to test it out. Realize there's a tiny little hole where the air is slowly leaking out. Fix it with duct tape. Realize you left the big plug thing open and the whole thing's deflating. Pump it back up. Watch your duct tape pop off, lose your patience, Shove the air mattress back under the couch and give your friend a pillow. Or you can get a sofa bed from Koala. Koala says they design their sofa beds to be as supportive and comfortable as their mattresses and enrich colors. Inspired by the Australian Outback, Koala sofa beds come in three sizes, so they're an option for small spaces without a guest room and they're easy to assemble at home. Everything slides, clicks, screws together without the need for extra tools. If you want to try one out, Koala offers 120 night risk free trial that's almost four months to make sure it's a good fit for your home plus free returns and no delivery or restocking fees. Upgrade your space with a stylish, customizable and elevated sofa bed. To get $100 off your new sofa plus fast shipping, go to us.koala.com unexplainable to get $100 off your new sofa. Koala Comfy, easy, sustainable Support for the show comes from NPR's Planet Money. Tariffs Meme Coins Girl Scout what do they all have in common? It's all about money, economics. It's everywhere. It's everything. Even when we least expect it. Planet Money is a show where the complexities of the economy actually make sense, where they're told through human stories from the job market to the stock market to prices at the supermarket, all in 30 minutes. I'm a huge Planet Money fan. I love the way they tell stories. They're clear, they're fun, they teach me a lot. They cover everything from the chaos that's happening in the economy right now to how the war on drugs brought us blueberries. And it all just goes down easy. You can tune into Planet Money every week for entertaining stories and insights about how money shapes our world, stories that can't be found anywhere else. Listen now to Planet Money from npr.

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[Noam Hassenfeld]

Shiny Teeth and me. Shiny, shiny teeth and me. Okay, it's time to talk about RFK junior.

[RFK Jr.]

I think fluoride is a poison.

[Noam Hassenfeld]

This is the guy behind the renewed push to get fluoride out of the water. The guy who's now in charge of America's health and science agencies. The same guy who's promoted all kinds of conspiracy theories, like how 5G is a sinister plot to rule the world.

[RFK Jr.]

They're putting in 5G to harvest our data and control our behavior.

[Noam Hassenfeld]

Or how HIV doesn't cause AIDS.

[RFK Jr.]

100% of the people who died in the first thousand who had AIDS were people who were addicted to poppers.

[Noam Hassenfeld]

Or how antidepressants are the reason we have so many school shootings.

[RFK Jr.]

There's tremendous circumstantial evidence. SSRIs and benzos and other drugs are doing this.

[Noam Hassenfeld]

The fact that this is the guy raising the alarm about fluoride, it's a big reason why it can feel so easy to write it off. Why a lot of public health experts might just wave away fluoride concerns without really getting into the details. This is fringe science. So what the health secretary is doing.

[Emily Oster]

Is smoke and mirrors.

[Noam Hassenfeld]

Emily can't see stand this kind of almost flippant response.

[Emily Oster]

I think that's a mistake in the way that we communicate. And the RFK case is a good one where, you know, he makes many claims. And some of those claims, I think, are more defensible than others. You know, so RFK thinks it's fine to drink raw milk. You know, like raw milk is more likely to make you sick than pasteurized milk. But the risks of raw milk are small. And I think that we will sometimes sort of give people the impression, like, only a crazy conspiracy theorist would, you know, buy into this raw milk mania. And if you're doing that, then, you know, you're a looney tune. Yeah, I think that kind of communication, which comes up a lot, is not helpful because it doesn't meet people where they are and help them understand why you hold the views that you hold. And then I think it pushes them away on topics where we really should be communicating. Like, we are really sure that this is something you should do. And so in the case of fluoride, to just say, you know, concerns about fluoride or conspiracy theory writ large is not helpful because if people look into it, they're not really going to find that.

[Noam Hassenfeld]

That's right, yeah. If you say the whole fluoride thing is a conspiracy and then people find a reasonable study that says there are actual downsides to fluoride at higher levels, it really does make it seem like a conspiracy.

[Emily Oster]

It exactly right. And if you are so dogmatic and you never allow for the possibility any information is counter to what you're saying, then as soon as someone sees some piece of information like that, you're going to lose them. And then, and then it's very hard to get them back. Once you have lost someone's trust, it's very hard to rebuild.

[Noam Hassenfeld]

So would you say that public health officials should be honest about the downsides of fluoride and then let people make their own decisions? Is that the strategy you're advocating?

[Emily Oster]

I would advocate a strategy of honesty, yes. I mean, I like, I tend to be like an over communicator, but I do think that we probably under communicate some of the nuance in the public health messaging that we said. It's obviously a tricky question in part because the public health community right now is RFK Jr. Yeah. So like that is. That makes it more difficult to talk about this question of like, what should public health say?

[Noam Hassenfeld]

Yeah, it is really hard because you see RFK really casting doubt on vaccines and we got a measles outbreak happening right now which is very different from very different slight levels of tooth decay. And I don't know, I can see the feeling of wanting to just tell people what to do, which makes me wonder, I guess. Do you think we can handle uncertainty?

[Emily Oster]

I do. I think people are not good at risks. Nobody's good at risk. No matter how smart you are. This is like people are not good at risks. But I, I fundamentally believe that people are smart enough to work through understanding some of this evidence. And I think it's disrespectful not to give them that grace to try because I don't think we're helping ourselves by telling people what to do. The thing we're doing now is not working.

[Noam Hassenfeld]

Yeah.

[Emily Oster]

So if you sort of said like, look, we as the public health authorities are going to decide, you know, fluoride is good, measles vaccine is good, raw milk is bad, and everyone's going to do exactly what we say. I mean, I like those are positions I'm aligned with, but the reality is you go and do that, and then what happens is people don't trust you and then you've like lost their trust on the raw milk, and then you lose their trust on the measles vaccine. And then now they're not doing any of those things. And if the only solution to that is then to yell that advice louder like, but really do, it's like, that's not helping. They're not listening and they are not believing you. And so I just don't think the system is working.

[Noam Hassenfeld]

I find this persuasive, but I don't know, I can get distracted. People can get distracted. I often come back to this poll from like 10 years ago that said something like 1 in 4Americans think the sun goes around the earth.

[Emily Oster]

Okay.

[Noam Hassenfeld]

And I don't know, maybe that might make us lean towards wanting to tell people what to do and not work through the data for themselves.

[Emily Oster]

Okay, that's a fair point. But let me tell you, like, I've built an entire career on the idea that like, people can understand graphs more than we thought they did.

[Noam Hassenfeld]

Yeah.

[Emily Oster]

But I think that the difference between these questions and whether the sun goes around the Earth is like, it doesn't matter for my life which thing goes around which thing. It's not that it wouldn't matter if it were reversed for the physics of the universe, but for my day to day life, it's not important. Whereas it is important. A choice I do have to make is, do I drink this kind of water or do I get my kid vaccinated or whatever these things are. I think people are more willing to engage on things that matter to them and more willing to think about them. We always take these examples like, oh, nobody can understand anything because they don't understand this basic thing about physics. But why would they think about that? It's like saying, like, people don't know what a sine or a cosine is.

[Noam Hassenfeld]

It's fair.

[Emily Oster]

I'd be like, oh, no, didn't you go to seventh grade? Didn't you get like, learn trigger? I bet you couldn't draw them for me. But the thing is, it doesn't come up.

[Noam Hassenfeld]

Okay? I mean, totally fair. On the flip side, has acknowledging uncertainty in public health ever backfired? Like, they laid out the data for everyone and the public just made some really bad decisions?

[Emily Oster]

Yeah, I'm sure the answer to that is yes. And, you know, I don't know if I have a specific example, but I think it's absolutely right that there are settings in which, at a minimum, I think we should Lead with here is the recommendation. And maybe that's sort of a different way to say this is like, I wouldn't lead a discussion of the measles vaccine by saying, let me start by laying out every piece of information we have about that. I think we have to lead the discussion with the best way to protect your kids and your family and the rest of everybody from measles is vaccination. And we know it is safe and effective, bottom line. But then the question is like, what do you say in response to people who are uncertain? And I think that's actually the tough thing about the communication here is it really does have to be kind of titrated to the person that you're talking to. I mean, this is why pediatricians are the best at this kind of stuff, because they are one on one with a person right in front of them, and they can feel, you know, somebody is just like, this is the thing. They're like, fine, you know, I don't want to hear any more about why. And then sometimes people need more of the why. And I think what's hard about the communication, I kind of err one way. I think other people would err it another way is, you know, how much do you lean into the assumption most people just want to be told what to do versus most people want a, like, pedantic, 3, 500 word explanation?

[Noam Hassenfeld]

Yeah, I mean, I think about what happened, I guess, five years ago now when Fauci's on the news at the beginning of the pandemic, trying to tell people what to do, and there's a lot of stuff that we're learning. He's trying to balance this collective action problem of getting people to do things that are important, while also not being sure how much uncertainty to communicate. Would it have been better, more responsible to lean into the uncertainty?

[Emily Oster]

I think it would have. I mean, I think one way to sort of organize this a little bit is like, the value of leaning into uncertainty and communicating that to people is highest when the uncertainty is highest.

[Noam Hassenfeld]

Yeah.

[Emily Oster]

When we were doing this communication in Covid, there was a lot of uncertainty, and they knew there was a lot of uncertainty. And I think the mistake there was to convey so little uncertainty in a moment when there was so much. And so then what happened is every day you were learning that what they said yesterday was not right. There were sort of many stages of this where communicating uncertainty would, I think, have really benefited because the certainty was sort of eroded almost immediately.

[Noam Hassenfeld]

Let's say we're three years down the line and There's a new head of the health agencies that's not a conspiracy theorist. What kind of message do you think that person should give to the American public? That, I guess, deals with uncertainty responsibly and also allows us to have the trust in science that we should have?

[Emily Oster]

I think the main thing I would say if that person asked me for advice, it would be ask people what their questions are and then try to engage those questions directly rather than assuming, you know, what their questions are or just assuming that you're going to tell them what to do. Figure out what they are concerned about, because it is not always a thing that you think, and then try to directly address those questions in an honest way.

[Noam Hassenfeld]

Is there an example of a question that you're thinking of that someone might have a different underlying motivation?

[Emily Oster]

I mean, I think in the space of vaccines, the set of questions that people have, you know, do vaccines cause autism? Why are there so many vaccines? You know, why do we need this particular vaccine? Why do we need the hepatitis B vaccine at birth? I think that is one where it's actually very simple to explain the answer to that question. But instead of explaining the answer to that question, often we're just like, well, that's what's recommended. It's on the vaccine schedule. Like, we put it on the vaccine schedule. And actually people would do better to explain why we have that and what are the potential other options if people are not comfortable with that.

[Noam Hassenfeld]

And then you think that would lead people to feel, I don't know, like they're having more agency, like they understand how the decisions are being made. Maybe they feel part of the decisions.

[Emily Oster]

That would be the hope.

[Noam Hassenfeld]

And it doesn't seem like you feel very hopeful.

[Emily Oster]

I'm not very hopeful. Sorry.

[Noam Hassenfeld]

Yeah.

[Emily Oster]

The truth is that, like, I was very frustrated during the pandemic with the messaging of the sort of public health officials. I'm frustrated with where we are now. I do wonder if we get a different administration in three years, whether that administration will have learned from the mistakes of the past. I don't think this is like an impossible thing to reset. And so maybe we'll get to some kind of balance.

[Noam Hassenfeld]

Okay, so that. That seems maybe a little. Maybe hopeful.

[Emily Oster]

Okay. A little hope. Leave you a little hope.

[Noam Hassenfeld]

This episode was produced by me, Noam Hassenfeld. We had editing from Julia Longoria, sound design from Christian Ayala, music from me, and fact checking from Melissa Hirsch. Meredith Haddonat runs the show. Jorge Just is our editorial director, and Bird Pinkerton bent over to pick up the second note again, it was from Aaron Bird High Noon the Abandoned Runway at jfk. Come alone. Thanks as always to Brian Resnik for co creating the show and if you have thoughts about the show, send us an email. We're@ unexplainableox.com you can also leave us a review or a rating. Wherever you listen really helps us find new listeners. You can also support this show and all of Vox's journalism by joining our membership program. You can go to vox.commembers to sign up. If you do, you'll be helping make this place run and you'll also get unlimited access to the reporting on Vox.com, you'll get exclusive newsletters and you'll get all our podcasts ad free. Think about it. Unexplainable is part of the Vox Media Podcast Network. We're off next week, but we'll be back in your feed on Monday, June 2nd.

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