From saunas to psychedelics, how a health reporter sorts science from hype

ELISSA NADWORNY, HOST: NPR's Will Stone reports on that line between proven medical treatments and alternative health practices.

WILL STONE, BYLINE: If you're envisioning study subjects smoking weed and sipping free booze, then you have a pretty good picture of this experiment.

NADWORNY: Weed versus alcohol, metabolic medicine and, yes, the science of sauna.

STONE: It's basically a chance for the sauna world to nerd out.

NADWORNY: In September, Will Stone traveled to Oslo, Norway, for the International Sauna Congress.

STONE: You have scientists, business operators, advocates. They're all here for a few days to talk about everything from the health benefits to the finer points of sauna culture.

NADWORNY: The program included party hopping and heat treatments in, quote, "floating sauna villages." So for this week's Reporter's Notebook, I wanted to talk to Will about arguably the toughest assignment at NPR.

I mean, come on. You got in a sauna in Oslo? Like, was it as blissful as it sounds? How jealous should I be?

STONE: Pretty jealous. This was not my normal trip into the field. Never had to wear a bathrobe before doing a a reporting trip before. Although I will say, when you go into a sauna with all your reporting gear and fully clothed, not as blissful as it...

NADWORNY: Yeah.

STONE: ...Might sound.

NADWORNY: Fair. OK, but seriously, what were the questions that were driving your reporting on the story?

STONE: A few things. I mean, this isn't really just about sauna - or sauna, sauna (ph). This is really about the broader field of heat therapy, which is something, when we look across - right? - cultures, the world had been doing for millennia - whether that's, you know, a sauna or steam bath or geothermal - right? - many places have these traditions.

And what's interesting to me is that the science, on the other hand, you know, is still pretty limited here. I mean, there's a whole field of thermal physiology, scientists who are looking at how our bodies respond to temperature, including heat. And there's plenty of research on kind of what happens to our bodies acutely in the heat, you know, with our heart rate or our blood vessels.

But the research on how you actually translate that into advice for people - and you can say definitively, oh, this is good for cardiovascular health or mental health - you know, these large human trials haven't been done. And this is a moment in - where the field is trying to basically organize itself so it can do the type of work that will really legitimize this as a - as, like, a lifestyle intervention. So I found it interesting to see the scientists kind of working through their process at this moment.

NADWORNY: OK, so you met scientists studying things like cardiovascular health, metabolism, mental health. What is the most surprising thing you learned about what the evidence actually supports versus kind of, like, what we see on Instagram or what the wellness industry claims?

STONE: Honestly, just how little we know. I was pretty surprised. When you ask the scientists who are doing these studies, you know, who are deeply immersed in the literature, they will be pretty frank and tell you there are just a lot of things we don't know, and - including, you know, social media loves protocols - right? - and kind of how long you should be doing it and how often to get this result. You ask the scientists, and they say, many different protocols have been tried. We really don't know, at this point, how to make recommendations that are very evidence-based.

And so while there are some really compelling studies that have been done - like, for example, in Finland, where everyone uses sauna, and those have shown strong associations between all kinds of health benefits and sauna use, like for cardiovascular health, for mental health - you can't just basically extrapolate that and say, well, this is good for everyone. You need to do the tough, painstaking studies.

And then on the flip side, what was interesting to me was that a lot of the claims that you'll see - for example, like, at your gym, you know, outside the sauna or outside a hotel, you know, a hotel sauna - are not necessarily evidence-based either, and they're actually kind of - we have better evidence to suggest it's not as dangerous as it can sound when you read one of those plaques.

NADWORNY: Oh, like the warnings outside the room, you said.

STONE: Yeah, I mean, definitely drinking in sauna, we can say, don't do that. But - so some of these are actually, you know, founded in real evidence, but others actually need to be updated. So it's - there's an interesting way in which there are certain claims being overhyped, and then in other areas where we do have some evidence, it just hasn't really trickled down.

NADWORNY: And I just want to make sure I understand you there. You mean, like, a sign that could say, like, don't stay longer than 10 minutes.

STONE: Exactly. There's...

NADWORNY: OK.

STONE: You know, and all of this is done because generally, it's hard to translate the work being done, you know, by a thermophysiologist in their lab to, you know, what goes up at a sauna in a hotel.

NADWORNY: At the Hilton sauna. Yeah.

STONE: Yeah. Exactly.

NADWORNY: Yeah (laughter). OK, so I want to turn to your larger beat. You have covered the alternative health movement for some time now, and I'm thinking things like peptides, psychedelics, high-intensity exercise. I'm curious, Will, what drives your reporting as you cover this moment in alternative health?

STONE: Yeah. You know, alternative is an interesting word because a lot of what I cover now is really part of the mainstream. And by that, I mean, like, you know, the wellness movement, longevity, the embrace of, like, biohacking and, you know, things that originate in Silicon Valley, wanting to optimize yourself - I mean, that's everywhere now on social media, and it's even being championed right at the highest levels of government.

So I think what drives my reporting is just understanding, you know, where the evidence lies for a particular treatment or remedy that's being promoted, and then the gap between what's being said about that and what we know. For me, I find that often with these trendy therapies, there's, like, a curious scientist there, you know, somewhere doing this research. And then what's actually happened to their findings, how those have taken on a new life on social media, is quite interesting because it's usually not at all - they would actually tell you.

So I think, you know, there's an interesting tension here with many of these therapies. I mean, we have peptides that are, like, the GLP-1 weight loss drugs. Those have been studied quite a bit in large trials, right? And many Americans are using them now. Then we have the wellness peptides, which have almost not been studied at all in any kind of human clinical trial. Some have almost no human data behind them. So the claims that they do any number of things for longevity or recovery or skin - often, those are not grounded in the kind of high-quality evidence that most people might imagine they were.

NADWORNY: Will Stone covers health and science for NPR. Thank you so much for talking with us.

STONE: Oh, it was fun. Thank you.