How You Perceive Colors & The Ways Heat Can Make You Healthy

Summary

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Podcast Summary: How You Perceive Colors & The Ways Heat Can Make You Healthy

Podcast: Something You Should Know
Host: Mike Carruthers
Guests: Corey Stamper (Lexicographer & Author), Bill Gifford (Health Writer & Author)
Date: March 30, 2026

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Episode Overview

In this episode, Mike Carruthers dives into two fascinating topics:

1. The science and language of color perception—how we define, describe, and respond to colors, featuring lexicographer Corey Stamper.
2. The emerging research on the health benefits of heat—from saunas to hot baths—with health journalist Bill Gifford.

Listeners will walk away with surprising insights into how something as simple as color names shape consumer choices, why describing color is so complex, and how controlled exposure to heat can foster better cardiovascular health and even improve mental wellbeing.

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Main Segments & Key Insights

1. How We Perceive and Talk About Color

Guest: Corey Stamper
Timestamps: 06:05–27:32

The Complex Intersection of Language and Color

• Describing color is surprisingly hard:
  “Talking about color is a little like talking about music… words never quite capture the whole thing.” – Mike Carruthers [05:25]
• Corey Stamper highlights the challenge of describing color—terms like "blue" can refer to a vast range of shades, and even seeing the same color can spark disagreement:
  “People have such strong associations with what they think a color is… they’ll argue with you about it.” – Corey Stamper [09:10]

How Color Naming Affects Perception & Marketing

• Companies invest heavily in color marketing, inventing endless unique names for subtle variations:
  “There's an entire industry devoted to naming consumer colors and it's called color marketing. And it is a blend of psychology, color science, and marketing.” – Corey Stamper [18:56]
• Choice overload: There are more “whites” and “grays” than more saturated colors, due to subtle undertone differences [20:53].
• Names evoke emotions and expectations (e.g., “Harvest Gold” sounds appealing but can be misleading when applied):
  “Color names are so fascinating because... all words evoke a feeling in us. Whether we want to have that feeling evoked or not, we have a reaction to them.” – Corey Stamper [24:01]

Color Psychology—Myth and Reality

• While “functional color” (like safety yellow on machinery) is proven to affect behavior, broad color-influence claims (e.g., “blue is calming”) are culturally specific and lack universal support [11:06].
• Experiments show that people’s reactions to room color are subjective and context-dependent [14:43].

Memorable Moment

• Corey’s real-world example of hair color disputes:
  “I used to dye my hair what I thought was purple… and people would say, ‘No, it’s pink.’ ‘No, it’s purple!’” [09:10]

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2. The Surprising Health Benefits of Heat

Guest: Bill Gifford
Timestamps: 28:31–71:00 (with repeat segment 51:22–71:00)

Why Heat Is (Sometimes) Good For You

• Contrary to conventional wisdom, research now links regular, safe heat exposure (especially via saunas and hot baths) to striking reductions in disease and all-cause mortality: “Frequent sauna users had about 40% the rate of fatal heart attacks, cardiovascular disease and all-cause mortality… That changed the conversation around heat.” – Bill Gifford [29:44]
• Saunas, hot tubs, and baths each provide controlled, beneficial rises in core body temperature—which the body responds to by increasing heart rate, expanding blood vessels, and producing “heat shock proteins” that offer cellular-level protection [33:38–35:02].

Scientific Findings

• Cardiovascular Health: Regular sauna use in Finland reduced fatal heart attacks by 60% ([35:20], [57:16]).
• Neuroprotection: Lower rates of Alzheimer’s and psychosis in frequent sauna users ([36:09], [58:05]).
• Adjunct in Cancer Treatment: Controlled “whole body hyperthermia” has boosted chemotherapy efficacy ([37:30], [59:26]).
• Mental Health: Whole-body heating therapy has shown dramatic reductions in depression symptoms, with effects lasting up to six weeks ([44:57], [66:54]).
• Key Mechanisms: Heat stimulates cleanup and repair at the cellular level via heat shock proteins ([34:03], [55:59]).

Accessible Ways to Use Heat

• “You can just take a hot bath, too, honestly… Hot baths have many of the same benefits as sauna, if not greater.” – Bill Gifford [41:50]
• Hot showers offer some benefit, but immersion in a bath is more effective [41:50], [63:47].

Exercise and Heat

• Exercise-induced heat (sweat) is a feature, not a bug:
  “Only about 20% of that energy that we create is translated into motion… The other 80% is heat.” – Bill Gifford [39:10], [61:06]
• Training in the heat can further boost adaptation—“a force multiplier effect” for fitness benefits ([39:10], [61:06]).

Heat vs. Cold Plunging

• Gifford contrasts the strong evidence for heat with the weaker science for cold plunging:
  “Jumping in cold water after you lift weights actually blunts your muscle growth.” – Bill Gifford [40:37], [62:33]

Culture, Ritual, and Enjoyment

• Sauna boredom is being tackled with rituals and performances, including German “Aufguss” sessions with music, dance, and towel-waving:
  “I once sat in a sauna and listened to a singer belt out an aria from the opera Tosca… it was powerful.” – Bill Gifford [43:47], [65:35]
• Many users report a mild euphoria—“sauna drunk”—after repeated sauna/cold cycles ([44:07], [66:03]).

Risks and Hydration

• Overhydration during or after heat exposure can be dangerous (“hyponatremia”), although it's rare:
  “If you drink too much water… you can essentially dilute your body… your cell membranes and neurotransmitters… stop working.” – Bill Gifford [47:35], [69:31]

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3. Rapid Intel: Chewing Gum Boosts Alertness

Host Tip: Research suggests chewing gum can help maintain attention and reaction time during monotonous tasks—especially mint flavors ([49:11], [71:07]).

• “Chewing gum increases brain arousal and keeps you mentally engaged, almost like giving your brain something small to do so it doesn't drift.”

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Notable Quotes & Timestamps

• “People have such strong associations with what they think a color is… they’ll argue with you about it.” — Corey Stamper [09:10]
• “There’s an entire industry devoted to naming consumer colors and it’s called color marketing.” — Corey Stamper [18:56]
• “Frequent sauna users had about 40% the rate of fatal heart attacks, cardiovascular disease and all-cause mortality.” — Bill Gifford [29:44]
• “Only about 20% of that energy that we create is translated into motion… The other 80% is heat.” — Bill Gifford [39:10]
• “I once sat in a sauna and listened to a singer belt out an aria from the opera Tosca. And there wasn’t a dry eye in the room, and we were all sweating, but, like, it was powerful.” — Bill Gifford [43:47]

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Key Timestamps for Further Listening

• 06:05 – Corey Stamper on color and language
• 11:06 – Color psychology and marketing
• 18:56 – How colors are named in industry
• 29:44 – Bill Gifford on health benefits of heat
• 33:59 – Cellular benefits of heat exposure
• 36:09 – Saunas, Alzheimer's, and mental health
• 41:50 – Can hot baths and showers substitute for saunas?
• 47:35 – Overhydration risks during heat exposure
• 49:11 – Chewing gum and mental alertness
• 65:35 – Sauna rituals and cultural practices

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Summary Conclusion

This episode unpacks why color both delights and frustrates us—because the words we use shape our perception as much as our eyes do. Meanwhile, it debunks fears around heat, highlighting compelling evidence that safe exposure (whether at a Finnish sauna or in your own hot bath) can deliver big health benefits, from a stronger heart to a happier brain.

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Recommended if you’re curious about:

• Why color names matter in daily life
• The science behind color psychology myths
• Easy ways to harness the power of heat for well-being
• How even chewing gum can give your brain a tiny edge

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Transcript

[Mike Carruthers]

This episode of Something youg Should Know is presented by Dutch. If your pet is still scratching and over the counter treatments aren't cutting it, Dutch connects you with a real licensed vet online, no waiting room and get prescription strength flea and tick meds delivered to your door. Use code [e-mail] for $40 off your membership today on something you should know. Have you ever been all alone but felt like someone was watching you?

[Bill Gifford]

What does that mean?

[Mike Carruthers]

Then? The interesting ways colors affect you.

[Corey Stamper]

If you go into the grocery store and you go to the meat counter, you'll notice that the meat is usually lying on some kind of green background. And the reason that is is because the green and the red play off of each other and it makes the red more vibrant.

[Mike Carruthers]

Also, how chewing gum affects your brain and the emerging science of how heat, like in a sauna, can seriously improve your health.

[Bill Gifford]

A series of studies from Finland found that frequent sauna users had about 40% the rate of fatal heart attacks, cardiovascular disease and all cause mortality. That's an astonishing finding and that changed the conversation around heat.

[Mike Carruthers]

All this today on something you should know. Here's a question for anyone with a dog or cat. Have you ever bought a flea treatment, used it exactly the way the instructions say? And the fleas, well, they didn't really care? Well, you're not imagining it. Over time, fleas actually build up a resistance to those over the counter treatments. Frontline advantage Seresto. They work for a while and then they don't. And Meanwhile you've spent 150, $200, maybe more, and your dog or cat still scratches. Well, here's what most people don't know. The stuff your vet prescribes Bravecto, Simparica, Nexcard, they hit differently. Prescription strength is a completely different class of treatment, but getting it usually means you make an appointment, you sit in the waiting room and then you get a bill that makes you wince. Which is where Dutch comes in. Dutch is an online vet service that connects you with a real licensed vet. No waiting room, no office visit fee. They can prescribe the same prescription strength flea and tick meds your vet would and get them delivered right to your door. So if your pet is still scratching and you've tried everything the pet store has to offer, it's time to stop guessing and go prescription and support us. And use code SYSK and you'll get $40 off your membership at dutch.com-u t c h.comdutch.com something you should know Fascinating intel the world's top experts and practical advice you can use in your life today. Something you should know with Mike Carruthers. You ever get that creepy feeling that you're being watched? What is that? Is it real? Well, that's what we're going to start with today on this episode of Something youg Should Know. Hi, I'm micahruthers. So that feeling that someone is watching you is pretty common. But very often you turn around to look and there's no one watching you. Psychologists say that feeling is usually an illusion created by your brain, but it's not random. You see, humans are highly tuned to detect eyes and the direction of their gaze, even in low visibility or out of the corner of your vision. It's an ancient survival skill. If something or someone is watching you, it could be a threat. The problem is your brain would rather make a false alarm than miss a real one. So it fills in gaps, a shadow or a movement, even just a vague sense of presence. And suddenly you think someone is staring at you. When you add in things like the spotlight effect, where we overestimate how much people notice us, and confirmation bias, that is, we remember the few times we were right that someone was staring at us. And then the illusion gets stronger. So that feeling you're being watched is probably not true, but the reason you feel it is very real. And that is something you should know. Talking about color is a little like talking talking about music. You can describe it, analyze it, even debate it, but unless you experience it, words never quite capture the whole thing. And color is stranger than we often realize. We attach emotions to color. We have favorite colors and ones we avoid, and then there are endless shades in between. But here's the really fascinating thing. How do we even know that the color I call blue looks the same to you? Then there's the bigger mystery of how color affects us. Why certain colors calm us, excite us, or even influence our decisions. So how did we come to define color in the first place? And why has it been such a surprisingly complicated thing to describe? Well, here to unravel the story of color and how we perceive it is Corrie Stamper. She is a lexicographer who spent nearly 30 years writing dictionaries for Merriam Webster, Cambridge Dictionaries and Dictionary.com. her work has appeared in the New York Times, the Guardian, New York Magazine, and the Washington Post. She's author of a book called True the Strange and Spectacular History of Defining color from Azure to zinc pink. Hey, Corey, welcome to something you should know.

[Corey Stamper]

Thanks so much, Mike. It's great to be Here.

[Mike Carruthers]

So you're a word person, having written dictionaries for years, and here you are talking about colors and words and colors. Well, you know, don't often. Those two words don't often show up in the same sentence. So why are you talking about color?

[Corey Stamper]

You would think they don't go in the same sentence a lot until you start actually talking about color. And then you realize how difficult it is to describe colors without using some kind of a color chip or some kind of a visual reference, because not everyone can see color. Not everyone has access to those visual references. So I really start the journey with color, for me, begins with language and not so much with color.

[Mike Carruthers]

You know, it sometimes seems that we complicate the discussion about color and the words about color. Because if I'm talking to you about something and I say, look over there. See that blue thing over there? I don't have to say, see the aquamarine. It's just blue. And yes, it's one of many blues. But just using the word blue is good enough in that situation that you know what I'm talking about. But it seems like there are so many different shades of blue, and a lot of times they're not necessary.

[Corey Stamper]

It's true. But there's also times when you want to be able to distinguish between all those blues. And, you know, a great example of this would be, I live in a part of the country that's near the ocean. I did not grow up near the ocean, but now I live near the ocean. And I have people who know the ocean tell me, oh, you know, when the ocean is this particular kind of blue, when the ocean is really sort of a gritty gray blue, you don't want to be out in it, because that means there's a lot of undercurrents that are dangerous. When the ocean is a much clearer blue that's better to be out in. I don't know what that means because I didn't grow up in the ocean. But clearly, there's two different blues that someone's talking about. And in those cases, those blues could be the difference between someone taking a boat out and sinking and someone having just a lovely Pacific troll around the harbor.

[Mike Carruthers]

Well, it would seem that words are kind of a lousy way. The best way to convey a color is to show you the color. Here's what I'm talking about. Rather than try to come up with words that describe it, here's what I mean. It's this color, sure.

[Corey Stamper]

But what happens when someone has impaired color vision or what happens when the color that I want to show you is on something, paper, let's say, that is going to be a different medium than the thing I need you to match it to. If I show you a paint chip and I say, I would like you, Mr. Mike Carruthers, to mix me a gallon of paint in this beautiful color that's called rejuvenate. And you say, great. Is that going on your bathroom wall? And I say, yes. And they say, all right. Would you like that in eggshell, satin, matte, semi gloss, or gloss finish? And I say, semi gloss. Why not? Sounds fancy. I get it home and I put it on my wall. Well, it doesn't match the chip because the chip is a different gloss. Or I get it home and I put it on my wall, and it's not that color rejuvenate anymore, because the light in my house is different from the light in the hardware store. So even when we have color chips and examples of color to show people, it's still not airtight. The other thing that's interesting about that is we think that it's very easy to show someone a color and say, this is what I mean by aqua. And the thing is, some people, particularly with sort of these borderline colors like aqua or magenta, people have such strong associations with what a color is in their head that they'll argue with you about it. I used to dye my hair what I thought was purple. And I was endlessly fascinated when I would go wait at the train station or I'd be in line at the grocery store, and people would say, oh, I love your hair. I wish I could dye my hair. And then they'd come up with a color that was not the color that was on my head. And I would argue with. People say, no, it's purple. It's pink, or it's blue. No, it's purple. Nope, it's pink. So people have such strong associations with what they think a color is when you give it a name or you show them a chip and say, this is aqua.

[Mike Carruthers]

And so what is this idea? I've heard people talk about? There's this color psychology that certain colors affect people. Is that a real thing?

[Corey Stamper]

It's a real thing in that colors do affect people. And marketers certainly take advantage of color names and colors to woo the consumer. There is something about. About color psychology, the idea that colors affect people in certain ways that is actually scientifically, factually true. And that part is called functional color. Functional color is using how people perceive colors in places like factories or on ships to help differentiate between different parts. So functional color was really important after World War II and factories because people who were not well trained were suddenly in the workforce and they kept shoving their hands into gears or touching moving parts. But if you paint those moving parts a really different color than everything else, like a red or a yellow, a color that people associate with warning they're going to be less likely to jam their hand into it. This comes up even in an example I give in the book is there's away. If you go into the grocery store and you go to the meat counter, you'll notice that the meat is usually lying on some kind of green background or that's divided up by green plastic grass. And the reason that is is because the green and the red play off of each other and it makes the red more vibrant. So you associate that brighter red with better quality meat. So functional color is sort of where color psychology gets applied. But in terms of these universal ideas that reds are the color of love and that blues are the color of calm, there's not a whole lot of science that goes behind that. And that's certainly not universally true across cultures either.

[Mike Carruthers]

And what about like in logos? Supposedly you see like the red and the yellow in fast food logos a lot. And, and like, because it's supposed to

[Corey Stamper]

do what I think the idea there is that reds, yellows, oranges are supposed to make you hungry. Right? They're, they're warm colors and hook onto your appetites, I think is maybe how a, a color marketer would put it. Oftentimes what you're seeing is just a market pattern. There's one successful fast food place that's got yellow and red and their logo. So, you know, we'll associate with that other fast food place by also using a different yellow and red in our logo. But yellow and red all the same. There's this very interesting language of color psychology that's been built up that I think becomes a self fulfilling prophecy in some ways. So lots of people are like, oh, well, you know, I painted my kitchen blue because I wanted it to be calming. And now it feels very cold and impersonal. And that's, you're, you're just repeating back what color psychologists tell you those things mean, whether you actually feel that way or not.

[Mike Carruthers]

Yeah, well, you know, things like earth tone. We hear earth tones are very, you know, earthy, I guess, but being in a room that's brown and beige, that supposedly has an effect. And the assumption is that it has the same effect on everyone that Enters it, but does it?

[Corey Stamper]

No. There were experiments and studies done throughout the 40s, 50s, and 60s about how color would affect people, mostly in institutional settings, so prisons or hospitals or other kinds of institutions. And these experiments went so far as to see, if we paint a barracks red, is that going to produce more aggressive soldiers? If we paint a hospital beige, is that going to mean that psychiatric patients are calmer? And the result is we just don't have enough good data to be able to say that that's the case, in part because color is not just a subjectively experienced thing, but it's also subjectively talked about. How can you have an experiment about color and how color affects a group of people without somehow people realizing that they're supposed to be keying in on the color? If you're used to being in a barracks that's painted gray and they put you in a barracks that's red, of course you would notice that difference. And of course you would probably have some kind of reaction to it, and maybe your reaction matches up with what your experimenter's hopes are. But it's so hard to know because these things are all such subjective experiences for us. And again, they're very culturally specific. It's hard to say. Yes, red makes everyone angry. Yes, blue calms everyone down.

[Mike Carruthers]

Well, it's all very confusing. And in a moment, I want to ask you about paint colors. So I started listening to this podcast, and I thought it was gonna make me feel guilty about existing on the planet, but it didn't. It's called Planet Visionaries. It's hosted by Alex Honnold. You may know him from Free Solo, and more recently Skyscraper Live, where he climbed Taipei 101, 101 story building. It's amazing to watch, but here he's talking to people who are actually doing something about the planet. And it's very encouraging. There's an episode with coral restoration pioneer Tituan Bernicotte and legendary oceanographer Sylvia Earle. And that one really got me, because they're talking about what's being done right now to protect and restore ocean ecosystems. And it makes you realize there's more progress happening than you hear about. And that's kind of the point. It's not doom and gloom. It's real people doing real work explained in a way that actually makes sense. So you come away thinking, okay, well, maybe this isn't hopeless. In partnership with the Rolex Perpetual Planet Initiative, this is Planet Visionaries Listen or watch on Apple, Spotify, YouTube, or where you're listening to this podcast

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[Mike Carruthers]

I'm speaking with Corey Stamper. She's author of the book True the Strange and Spectacular History of Defining Color from Azure to Zinc Pink. So, Corey, you go into a paint store and you will see so many odd, weird, different names for colors. Who comes up with those names that this one looks just like that one, but it has a completely different name. And this one is named. This color is called Champagne. It doesn't look anything like the champagne I've ever drank. It was like, where does this all? Who's doing this?

[Corey Stamper]

There's an entire industry devoted to naming consumer colors and it's called color marketing. And it is a blend of psychology, color science, and marketing. And there are hundreds, possibly thousands of people who are involved in color marketing. Paint stores are the thing that we think of the most because all the colors are right there. And you know, there seems to be thousands of colors in front of you and all of the names seem to be very of the moment. Color naming is so specific. And the thing that is so fascinating about it is there are different fields of color naming specialists. So you have people who work in paint stores and they talk very specifically about how paint is a particular product that can only have particular kinds of names. If you talk to someone who does fabric dyeing, they will talk about how commercially fabrics are all named particular things for particular markets. So if I'm shopping at, you know, Macy's or something like that, I'm going to get the same colors as someone who's shopping at a very high end couturier. But those color names are going to be different because I'm in a different consumer bracket than the people who are shopping at the high couturier store.

[Mike Carruthers]

Well, it does to an outsider like me, seem unnecessarily complicated. You go to a paint store and say, I want white. Well, gee, my God, I mean, there's a million different whites, but you would think white would be white.

[Corey Stamper]

I would probably guess that there are more whites and grays and even blacks than There are more chromatic colors. Reds, oranges, yellows, greens. Because whites can tip in any chromatic direction. You can have a white that's got a little bit of a yellow undertone or a little bit of a green undertone or a little bit of a purple undertone. You can't have a purple that's got a green undertone that's a different color. So there. There are. White is not white.

[Mike Carruthers]

Is all this confusion and bizarreness deliberate, or is it just so many people are doing so many things with color, it's just a big mess or what?

[Corey Stamper]

It's a little of both. Color is very much like language in that it's very elastic. So the way that we talk about color changes depending on our context, the way that we encounter color changes depending on our context. And one of the great things about both color and language is that it's flexible enough to accommodate all of that. So a painter can talk about their palette, and a scientist can talk about enamel coatings for your refrigerator. And color and language can accommodate both of those fields. But what gets murky is that we're not all in all of those fields. So it's hard to say, okay, sure, titanium oxide. Is. That's that white? But over here, the painter calls it titanium white. And both the painter and the color specialist argue and say, no, no, no, no, no, the other one's wrong, or that's right. And when I just say, well, that's just white. All of these things are so complicated in part because the way language grows is through iteration. So I've got blue. I've got one color blue. It might get 15 different names over the course of the English languages. Reckoning with that color doesn't mean that that color is 15 different colors. And it doesn't mean that we need to get rid of all of the redundancy in language. It just means that's what an elastic, living, breathing language and discipline do. It. It iterates well.

[Bill Gifford]

It.

[Mike Carruthers]

It's interesting to me that the name of a color can influence what you think about that color. And I have, I think, a really good example of that. I remember many, many years ago of painting, painting a room, and I saw this color, and it was called Harvest Gold. And I thought, well, how lovely, how wonderful. Looks great. I looked at the paint chip and I said, great. So I painted the room harvest gold. It was just gas. It looked like vomit. It was horrible. But it sounded great, and the little chip looked great. But on the whole room, it was terrible.

[Corey Stamper]

I have done the same Thing, I have repainted whole rooms because of that. Color names are so fascinating because they are meant. All language, all words evoke a feeling in us. Whether we want to have that feeling evoked or not, we have a reaction to them. Now, color marketers take advantage of that reaction. And that's one of the things about color names and talking about color that gets so interesting is that the language we use for color affects our response to it. There have been studies done on how names, particularly in commercial contexts, affect a person's willingness to buy an item that is that color. And they found these various groups found that a fancier color name brought in more dollars because people expect something with a fancy name to be more expensive. So calling your wall color brown is not going to make anyone buy it. We're calling your wall color yellow. Well, that doesn't sound very exciting. But if you call it Harvest Gold or Sunrise, well, now, now, that's evoking a feeling in me, even if it's the same color. But maybe I don't know enough about color science and illuminance and things like that to realize that Harvest Gold in the paint catalog, in the paint store is actually going to turn out to be this really gross, pukey color on my wall. Because I don't take into account the fact or I don't know to take into account that the light is going to be different and the space itself is going to change how I see that color. And even things like, oh, I have brown wood trim, and I didn't realize that that brown wood trim would make that color go less yellow and more brown, and now it just looks gross and dull. These are all things that the feeling that a color name gives us and the feeling we have about a color is so context specific. And language is very much that way, too. So color names, yeah, they're. They're meant. They're meant to make us do a thing with that color. And often it's to buy that color and put it on our wall.

[Mike Carruthers]

Well, you know, it's interesting. For as long as we've been doing this podcast, for several years now, I have tried to find a really good expert on how color affects people. And it's been very difficult to find anyone. And you've pretty much explained why, because color is so subjective and so confusing that it's. I guess it's hard to know how color affects people. And I appreciate your explanation through the, through the eyes of a word person about how color works. I've been speaking with Corey Stamper who for 30 years wrote dictionaries at Merriam Webster Cambridge dictionaries and dictionary.com and she's author of a book about color. It's called True the Strange and Spectacular History of Defining Color From Azure to Zinc Pink. And you can find a link to that book in the show Notes. And Corey, thank you. Thanks again. Appreciate it.

[Corey Stamper]

Thanks so much for having me, Mike. It's been great.

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[Mike Carruthers]

We've all heard the warnings about heat. On a hot day, it can dehydrate you, cause heat exhaustion, and in extreme cases, heat can even be deadly. But what if heat isn't just something to avoid? New research suggests that when used the right way, heat can actually be good for you, improving your health, boosting athletic performance, and even helping you live longer. From saunas to hot baths to heat training, scientists are discovering that exposing your body to heat may trigger some powerful benefits. My guest, Bill Gifford has been exploring this fascinating science. He's a veteran magazine writer and editor who covers cutting edge health research. He's author of a book called Hot how the Hidden Power of Heat Makes us Stronger. Hi Bill. Welcome to something you should know.

[Bill Gifford]

Hey, thanks for having me, Mike.

[Mike Carruthers]

So this idea that heat is good for you, I've heard, you know, put a heating pad on it if it's sore or something. But this idea that overall health can be improved with heat is news to me. So what is the argument here?

[Bill Gifford]

Yeah, so it actually surprised me as well because I am not somebody who instinctively likes hot weather. Heat waves Summer even. I don't even. Didn't even like sauna five years ago. And we're told that heat is kind of the devil, that heat will kill us. And it's true that, that excessive heat can be dangerous, but there's sort of an emerging strand of, of scientific research and athletic knowledge that's now showing that that heat can be healing as well, and it can even improve performance for athletes.

[Mike Carruthers]

And when you talk about heat, what is it? You mean heat? What kind of heat? Like heat from a heater, heat from the sun, heat from going to a hot climate. Like, what kind of heat are we talking about?

[Bill Gifford]

I'm really talking about targeted, controlled, safe, emphasis on safe exposure to temperatures higher than normal, let's say. So, for example, the sauna, which is an ancient tradition in Finland, but also in many cultures around the world, they go into these spaces that are extremely hot and they derive social, communal, just basic cleanliness type benefits, but also health benefits. And so a series of studies from Finland, actually from about 10 years ago, found that frequent sauna users had about 40% the rate of fatal heart attacks, cardiovascular disease, and all cause mortality. So your chance of dying is reduced by half if you go to sauna every other day. That's an astonishing finding. And that changed the conversation around heat from something that's inherently dangerous to something that is dangerous in some situations and potentially healing in other situations.

[Mike Carruthers]

I've never gotten the sauna thing. I never understood it. I've been in one and I thought, well, you know, it's really hot.

[Bill Gifford]

It's really hot, right? Can I get out of here? Can I get out of here?

[Mike Carruthers]

Because I don't like the heat. I mean, I don't see the pleasure in it. And I thought that's why people did it. Like, yeah, there was some vague health benefits to maybe doing it, but that the vagueness of it all didn't counter the fact that it's hot in here and I want out.

[Bill Gifford]

Yeah. And that's a natural reaction to any extreme environment. I mean, it's the same reaction. These people who go into cold plunges, right? It's like an instant panic and you want to leave. And once you kind of fight through that, there are some benefits that happen.

[Mike Carruthers]

But interestingly, I like a hot tub. I mean, I like.

[Bill Gifford]

Aha, there you go.

[Mike Carruthers]

I like hot water, but I don't like hot because then I sweat and then it's uncomfortable and sticky.

[Bill Gifford]

And you're sweating in the hot tub as well.

[Mike Carruthers]

What do you mean?

[Bill Gifford]

You're. You sweat when you're in hot water, your body's natural response when as your temperature becomes elevated is to try and cool yourself down. Because we have this, this idea of homeostasis. We want to stay at a stable, within a stable temperature range. So your body is fighting to stay cooler whether you're in a, in a sauna or a, or a hot tub.

[Mike Carruthers]

Oh, I didn't know that.

[Bill Gifford]

It's just washed away in the, in the. Yeah.

[Mike Carruthers]

Well, that's kind of gross.

[Bill Gifford]

I hope I didn't, hope I didn't ruin the hot tub for you.

[Mike Carruthers]

Well, it's just that now I know I'm sitting in a pool of everybody else's sweat, so I don't know, maybe you just did ruin it for me, you know.

[Bill Gifford]

Oh, sorry.

[Mike Carruthers]

Yeah, that's all right.

[Bill Gifford]

So, but interesting point though. The, the hot tub is actually more effective, raising your core body temperature than a sauna is.

[Mike Carruthers]

And is raising my core temperature a good thing?

[Bill Gifford]

Yes, weirdly, you know, we're told that having a fever is bad and raising your body temperature is bad, but some good things happen when you get your body temperature slightly, slightly elevated. So we're talking like 101 fahrenheit and some adaptations take place which I can get into later.

[Mike Carruthers]

Well, let's get into it now. What are those benefits?

[Bill Gifford]

For starters, there are cardiovascular benefits. So your heart rate increases as your body, like I said, is trying to, trying to stay cool. So you send more blood to the skin, right? And so you have more blood flow. And then that in turn, in addition to the, the heart rate elevation, you get your, your blood vessels are dilated so your circulation improves. So that's a good thing. And then if you go a little deeper, even down to your, inside your cells, there are these things called heat shock proteins. Those are like the, I call them like the maintenance department of your cells. But they're also like some scientists I talked to said, they're like the mommy proteins and they kind of take care of the other proteins, basically the machinery inside your cells, and they clean things up and they keep your DNA intact and keep that from breaking down. So it makes you more stress resistant, essentially on a cellular level. Pretty cool.

[Mike Carruthers]

So you said earlier that people in saunas, the research shows that they have a lower mortality rate that their health benefits. Because what's going on? Like, what is it that if I didn't go in that sauna, I might have died from that? Now the sauna is protecting me from.

[Bill Gifford]

I mean, you're actually literally on point when you say protecting you from something you might have died from. This research started in Finland back in the 80s and Finland had a huge problem with middle aged men dying of heart attacks, sudden heart attacks, dropping dead. And so they did this huge study of cardiovascular risk factors and they asked them about all aspects of their lives, including sauna use. And so 30 years later, these researchers looked at the data and found that the men who said they used sauna the most, 60% reduced rate of those fatal heart attacks. So it is literally protecting, it protected those guys from dying of a heart attack.

[Mike Carruthers]

So it's heart, it's cardiac, it's cardiac issues. Yes. Yeah.

[Bill Gifford]

Starts with cardiovascular health and then a lot of benefits radiate out from there. For example, they looked again at the data and found that the guys who use sauna every other day or every day had about one third the rate of Alzheimer's disease. That gets your attention.

[Mike Carruthers]

Well, this is surprising to me. I've never heard this about men in saunas before. But are there other ways to heat up or must you create a sauna like experience in, in order to get these heat benefits you're talking about?

[Bill Gifford]

Well, there are infrared saunas, which have a different kind of heat, but also have been found in Japan to have some cardiovascular benefits and have been used actually to treat patients with serious heart conditions. But also just taking a hot bath has been found to have very similar benefits. So again, in Japan, a huge study found that people taking hot baths every night had reduced their cardiovascular disease risk by, by about a quarter, by about 25%.

[Mike Carruthers]

Are there other diseases or conditions that this is good for? Like does heating you up like inhibit cancer growth or. I mean, is there anything else or is it mostly cardiovascular stuff?

[Bill Gifford]

It's interesting. So the Finnish studies, which are the best sort of long term studies of heat exposure in humans, found that there was no effect on cancer, but it kind of helped with everything else. So not only heart stuff, stroke, Alzheimer's, potentially psychosis, they have fewer episodes, psychotic episodes in their life. But I'm going to go back to cancer, if you will, because it's an interesting topic. In Germany for decades they would, they would use what they called whole body hyperthermia. So basically heating up cancer patients in a kind of infrared, little mini, infrared sauna contraption appeared to help their chemotherapy treatments be more effective. So that was a whole thing in Germany, heating up cancer patients.

[Mike Carruthers]

Is it still.

[Bill Gifford]

Well, now there's something called focused ultrasound, which is kind of an exciting new area of cancer treatment that's being pursued here in the US where you used focused ultrasound, it's essentially administering very localized heat treatment on cancer tumors. I think the idea broadly is that the heat weakens the cancer cells and allows the medicine to penetrate them more effectively.

[Mike Carruthers]

There are other ways to get hot other than sitting in heat. Like you can go to the gym and the gym is 72 degrees, but you could work yourself up into a sweat. Does that count?

[Bill Gifford]

Yep. Oh, yeah, absolutely. And it's interesting. When we exercise, this is an astonishing fact. When we exercise, we're producing all this energy in our muscles and our mitochondria. Only about 20% of that energy that we create is translated into motion or effort or lifting. The other 80% is heat. It's like a byproduct. There are some, obviously there are similar benefits to exercise, but as we work out in that 72 degree gym, we get quite hot and we sweat. Right. And our body's trying to cool us down. Athletes have found that there are adaptations that take place as we work out in hot conditions that sort of improve and extend on the benefits, on the inherent benefits of exercise. So you get a sort of a force multiplier effect if you work out in a slightly hotter situation. It's called heat adaptation. And it's very similar to the effects of sitting in a sauna or sitting in your hot tub or sitting in a hot bath.

[Mike Carruthers]

Well, it's interesting because there's been a lot of talk lately, and you mentioned it before, about the cold plunge of taking a cold shower, putting your face in cold ice water. But that's just the opposite of what you're talking about. But they must be related somehow.

[Bill Gifford]

If you dig into the science, the data supporting cold plunging is actually quite a bit weaker than the data supporting this targeted heat exposure that I'm talking about. And so that's not to say that you shouldn't do it, but I think the expectation that cold plunging is a great thing to do after, like a strength workout, I think that's incorrect. There's a lot of research showing that jumping in cold water after you lift weights actually blunts your muscle growth. So you're blunting the benefits of the workout you just did.

[Mike Carruthers]

Well, I can't say I'm sorry to hear that. I'm not a big cold plunge guy. I'd rather be in a heated pool, frankly. I want to ask you about, like, so what do we do with this information about targeted heating? In just a moment, I'm speaking with Bill Gifford. He's author of the book Hot how the Hidden Power of Heat makes us stronger. And so, Bill, I want to get a sense of, like, what's the prescription here? You've talked about the benefits of a sauna, but not everybody has access to one or is likely going to sit in a sauna every day or every other day. So what can you do?

[Bill Gifford]

I mean, you can just take a hot bath, too, honestly, like, if that's where you're at, the hot bath, again, has been found to have many of the same benefits as sauna, if not, if not greater. In fact, what about a hot shower? Not quite the same thing, because you're not getting as much of a heat transfer to your body. You're just kind of sitting in the sprinkling shower. But if you're actually immersed in the hot water in the tub, then your core temperature is going up and you're getting those benefits of heat.

[Mike Carruthers]

I think one of the things about sitting in a sauna is. I've been in a sauna once, but it's kind of boring. Like, there's not much to do.

[Bill Gifford]

There's this interesting sort of cultural phenomenon that's kind of developed. I think it started in Germany, but they actually do these performances in a sauna. They'll have these sort of attractive performers come into the sauna, and there'll be like 40 people in there, and they'll play music or they'll. They'll kind of dance around and they'll wave these towels, like blasting heat, moving the heat, the hot air around the room in your face. And, like, it's very intense. And then that. That's called Aufgoose. It's crazy. It's like a whole culture. There's. There's competitions, there's costumes. There's people. There are people who do, like, miniature plays and skits in the sauna. I once sat in a sauna and listened to a singer belt out an aria from the opera Tosca. And there wasn't a dry eye in the room, and we were all sweating, but, like, it was powerful. And so that cures the boredom problem. So just. You're not just sitting there stewing in your own juices. You know, you've got something to sort of divert your attention.

[Mike Carruthers]

You're making it sound so appealing.

[Bill Gifford]

It's very cool.

[Mike Carruthers]

Is there a benefit to. When you're done and you step out back into the cool. Like, is that. Is that a rush or is that. Is that not why people do it? That's more kind of like hitting yourself with a hammer and then stopping.

[Bill Gifford]

There's a little bit of the hitting yourself with a hammer thing, I won't lie. But there is a phenomenon. You almost get sauna drunk or sauna high. So if you go in to the hot room and then you either you cool off or you do a. A quick cold dip, you do that a few times. Many people have noticed. I noticed you get almost like sauna drunk. Like you're. You're just a little bit euphoric. You know, you don't really care about the things that were bothering you before you went in. And honestly, I noticed that.

[Mike Carruthers]

Well, it's certainly interesting, but does modern medicine typically, like, if you were to ask people in the medical profession, they would, oh, yeah, we know about that. Or is this all fairly new stuff?

[Bill Gifford]

You know, I think medicine is starting to take some notice of it. I mean, your doctor might or might not prescribe you sauna sessions. But one thing that I found that was really interesting is that what they call, again, whole body hyperthermia, basically heating you up to a certain level, is. Is being actively researched as a potential treatment against severe depression. And there have been some, like, pretty striking results. For example, there was a study done initially in Germany by, you know, German and American researchers where they put people in these same devices that I talked about that they used to use for treating cancer patients. So they put very depressed people in these things, heated them up to 101Fahrenheit for an hour, which is not fun. I tried it myself. It's not fun. But then afterwards, their depression symptoms were cut in half and even more, which is way better than any antidepressant drug. Antidepressants only work in about 20 to 40% of patients. Even better, they went back a month later thinking that the antidepressant effect would be. Would have evaporated, would be gone. And they found that they were still not depressed, still less depressed, and again six weeks later. So it lasted six weeks. And so that got some attention. And then there are various studies happening right now, and other studies have come out since then kind of confirming this result, which is great news, I think.

[Mike Carruthers]

I would think one of the concerns, if you're using heat for the health benefits that it supposedly produces, that one of the concerns would be hydration, because heat will evaporate water and that you could get dehydrated from doing the kinds of things you're talking about.

[Bill Gifford]

You know, everybody walks around with a water bottle now everywhere, right? On the airplane, in a theater, in a restaurant. Everybody's got their sort of emotional support water bottles. And I was kind of shocked and amazed to discover that drinking too much over hydration. And again, this is related to heat in the sense that you need to hydrate to replace the water you lose from sweat, etc. Over hydration can actually kill you or make you sick.

[Mike Carruthers]

So how does that work? Seems like you'd have to drink an awful lot of water for that to happen.

[Bill Gifford]

If you drink too much water, these mechanisms in your body that regulate your fluid level and your salinity and all this kind of stuff, you can essentially dilute your body to a situation called hyponatremia, which basically means you're not salty enough, you don't have enough sodium, so that your cell membranes and neurotransmitters and things like that kind of stop working. It's a very serious situation. It's relatively rare, but it. It happened to Brook Shields about a year ago, year and a half ago, she nearly died. So we need to be careful around the hydration situation. But I think the big takeaway is that that, you know, targeted, limited exposure to heat can actually have some benefits in terms of our physical, mental, emotional health.

[Mike Carruthers]

Well, you know, when I hear about heat, I think, well, that's something to avoid because, you know, heat can be dangerous and people get sick and die from exposure to heat. But I've never heard of all these health benefits you're talking about. And you're a well regarded writer that clearly has researched this. I find it fascinating. I've been talking to Bill Gifford. He is a veteran magazine writer and editor who covers cutting edge health research. And he is author of a book, how the Hidden Power of Heat Makes Us Stronger. And there's a link to that book in the show notes. Bill, great, thanks. Appreciate the info.

[Bill Gifford]

Thanks, Mike. This is great. I loved all your questions. This was great.

[Mike Carruthers]

It sounds too simple, but research shows that chewing gum can improve alertness and help you stay focused, especially during long or repetitive tasks. In studies, people who chewed gum performed better on tests of attention and reaction time, particularly as tasks went on and mental fatigue set in. Scientists think it works because chewing gum increases brain arousal and keeps you mentally engaged, almost like giving your brain something small to do. So it doesn't drift. There's even some evidence that mint flavors like peppermint may add a slight boost, possibly because they stimulate scent. But here's the catch. Chewing gum won't make you smarter or better at complex thinking. What it can do is help you stay in the zone longer. So if your focus starts to slip, you might not need more coffee. You might Just need a stick of gum. And that is something you should know. This program is produced by Jennifer Brennan and Jeff Haveson. Executive producer is Ken Williams. I'm Mike Carruthers. Thanks for listening today to something you should know. We've all heard the warnings about heat. On a hot day, it can drop, dehydrate you cause heat exhaustion, and in extreme cases, heat can even be deadly. But what if heat isn't just something to avoid? New research suggests that when used the right way, heat can actually be good for you, improving your health, boosting athletic performance, and even helping you live longer. From saunas to hot baths to heat training, scientists are discovering that exposing your body to heat may trigger some powerful benefits. My guest Bill Gifford has been exploring this fascinating science. He's a veteran magazine writer and editor who covers cutting edge health research. He's author of a book called Hot how the Hidden power of Heat Makes us Stronger. Hi, Bill. Welcome to something you should know.

[Bill Gifford]

Hey, thanks for having me, Mike.

[Mike Carruthers]

So this idea that heat is good for you, I've heard put a heating pad on it if it's sore or something. But this idea that overall health can be improved with heat is news to me. So what is the argument here?

[Bill Gifford]

Yeah, so it actually surprised me as well because I am not somebody who instinctively likes hot weather, heat waves, summer even. I don't even, didn't even like sauna five years ago. And we're told that heat is kind of the devil, that heat will kill us. And it's true that excessive heat can be dangerous, but there's sort of an emerging strand of scientific research and athletic knowledge that's now showing that heat can be healing as well and it can even improve performance for athletes.

[Mike Carruthers]

And when you talk about heat, what does it you mean what kind of heat? Like heat from a heater, heat from the sun, heat, heat from going to a hot climate. Like what kind of heat are we talking about?

[Bill Gifford]

I'm really talking about targeted, controlled, safe, emphasis on safe exposure to temperatures higher than normal, let's say. So, for example, the sauna, which is an ancient tradition in Finland, but also in many cultures around the world, they go into these spaces that are extremely hot and they derive social, communal, just basic cleanliness type benefits, but also health benefits. And so a series of studies from Finland actually from about 10 years ago, found that frequent sauna users had about 40% the rate of fatal heart attacks, cardiovascular disease, and all cause mortality. So your chance of dying is reduced by half if you go to sauna every other day. That's an astonishing finding. And that changed the conversation around heat from something that's inherently dangerous to something that is dangerous in some situations and potentially healing in other situations.

[Mike Carruthers]

I've never gotten the sauna thing. I never understood it. I've been in one, and I thought, well, you know, it's really, really hot.

[Bill Gifford]

It's really hot, right? Can I get out of here, please? Can I get out of here?

[Mike Carruthers]

Because I don't like the heat. I mean, I don't see the pleasure in it. And I thought that's why people did it. Like, yeah, there was some vague health benefits to maybe doing it, but that the vagueness of it all didn't counter the fact that it's hot in here and I want out.

[Bill Gifford]

Yeah. And that's a natural reaction to any extreme environment. I mean, it's the same reaction. These people who go into cold, cold plunges, Right. It's like an instant panic, and you want to leave. And once you kind of fight through that, there are some. There are some benefits that happen.

[Mike Carruthers]

But interestingly, I like a hot tub. I mean, I like a hot.

[Bill Gifford]

There you go.

[Mike Carruthers]

I like hot water, but I don't like hot because then I sweat, and then it's uncomfortable and sticky, and you're

[Bill Gifford]

sweating in the hot tub as well. What do you mean you sweat when you're in hot water? Your body's natural response when as your temperature becomes elevated, is to try and cool yourself down. Because we have this. This idea of homeostasis. We want to stay at a stable. Within a stable temperature range. So your body is fighting to stay cooler whether you're in a. In a sauna or a. Or a hot tub.

[Mike Carruthers]

Oh, I didn't know that.

[Bill Gifford]

It's just washed away in the. In the. Yeah.

[Mike Carruthers]

Well, that's kind of gross. All right.

[Bill Gifford]

I hope I didn't. Hope I didn't ruin the hot tub for you.

[Mike Carruthers]

Well, it's just that now I know I'm sitting in a pool of everybody else's sweat, so I don't know, maybe you just did ruin it for me, you know.

[Bill Gifford]

Oh, sorry.

[Mike Carruthers]

Yeah, that's all right.

[Bill Gifford]

So, but interesting point, though. The hot tub is actually more effective at raising your core body temperature than a sauna is.

[Mike Carruthers]

And is raising my core temperature a good thing?

[Bill Gifford]

Yes, weirdly, you know, we're told that having a fever is bad and raising your body temperature is bad, but some good things happen when you get your body temperature slightly, slightly elevated. So we're talking like 101 fahrenheit and some adaptations Take place, which I can get into later.

[Mike Carruthers]

Well, let's get into it now. What are those benefits?

[Bill Gifford]

For starters, there are cardiovascular benefits. So your heart rate increases as your body, like I said, is trying to, trying to stay cool. So you send more blood to the skin, right? And so you have more blood flow. And then that in turn, in addition to the, the heart rate elevation, you get your, your blood vessels are dilated so your circulation improves. So that's a good thing. And then if you go a little deeper, even down to your, inside your cells, there are these things called heat shock proteins. Those are like the, I call them like the maintenance department of your cells, but they're also like some scientists I talked to said they're like the mommy proteins and they kind of take care of the other proteins, basically the machinery inside your cells and they clean things up and they keep your DNA intact and keep that from breaking down. So it makes you more stress resistant essentially on a, on a cellular level. Pretty cool.

[Mike Carruthers]

So you said earlier that people in saunas, the research shows that they, they have a lower mortality rate that they, their health benefits. Because what's going on? Like what is it that if I didn't go in that sauna, I might have died from that? Now the sauna is protecting me from.

[Bill Gifford]

I mean, you're actually literally on point when you say protecting you from something you might have died from. This research started in Finland back in the 80s. And Finland had a huge problem with middle aged men dying of heart attacks, sudden heart attacks, dropping dead. And so they did this huge study of cardiovascular risk factors and they asked them about all aspects of their lives, including sauna use. And so 30 years later, these researchers looked at the data and found that the men who said they use sauna the most, 60% reduced rate of those fatal heart attacks. So it is literally protecting, it protected those guys from dying of a heart attack.

[Mike Carruthers]

So it's heart, it's cardiac, it's cardiac issues.

[Bill Gifford]

Yeah. Starts with cardiovascular health and then a lot of benefits radiate out from there. For example, they looked again at the data and found that the guys who use sauna every other day or every day had about one third the rate of Alzheimer's disease. That gets your attention.

[Mike Carruthers]

Well, this is surprising to me. I've never heard this about men in saunas before. But are there other ways to heat up or must you create a sauna like experience in order to get these heat benefits you're talking about?

[Bill Gifford]

Well, there are infrared saunas which have a different kind of heat. But Also have been found in Japan to have some cardiovascular benefits and have been used actually to treat patients with serious heart conditions. But also just taking a hot bath has been found to have very similar benefits. So again, in Japan, a huge study found that people taking hot baths every night had reduced their cardiovascular disease risk by about a quarter, by about 25%.

[Mike Carruthers]

Are there other diseases or conditions that this is good for? Like, does heating you up, like inhibit cancer growth or. I mean, is there anything else or is it mostly cardiovascular stuff?

[Bill Gifford]

It's interesting. So the Finnish studies, which are the best sort of long term studies of heat exposure in humans, found that there was no effect on cancer, but it kind of helped with everything else. So not only heart stuff, stroke, Alzheimer's, potentially psychosis, they have fewer episodes, psychotic episodes in their life. But I'm going to go back to cancer, if you will, because it's an interesting topic. In Germany, for decades, they would use what they called whole body hyperthermia. So basically, heating up cancer patients in a kind of infrared, little mini infrared sauna contraption appeared to help their chemotherapy treatments be more effective. So that was a whole thing in Germany, heating up cancer patients.

[Mike Carruthers]

Is it still?

[Bill Gifford]

Well, now there's something called focused ultrasound, which is kind of an exciting new area of cancer treatment that's being sort of pursued here in the US where you used focused ultrasound. It's essentially administering very localized heat treatment on cancer tumors. And I think the idea broadly is that the heat sort of weakens the cancer cells and allows the medicine to penetrate them more effectively.

[Mike Carruthers]

There are other ways to get hot other than sitting in heat. Like you can go to the gym and the gym is 72 degrees, but you could work yourself up into a sweat. Does that count?

[Bill Gifford]

Yep. Oh, yeah, absolutely. And it's interesting, you know, when we exercise, this is an astonishing fact. When we exercise, you know, we're producing all this energy in our muscles and our mitochondria. Only about 20% of that energy that we create is translated into motion or effort or lifting. The other 80% is heat. It's like a byproduct. Obviously, there are similar benefits to exercise, but as we work out in that 72 degree gym, we get quite hot and we sweat, right. And our body's trying to cool us down. Athletes have found that there are adaptations that take place as we work out in hot conditions that sort of improve and extend on the benefits, on the inherent benefits of exercise. So you get a sort of a force multiplier effect if you work out in a slightly hotter situation. It's called heat adaptation. And it's very similar to the effects of sitting in a sauna or sitting in your hot tub or sitting in a hot bath.

[Mike Carruthers]

Well, it's interesting because there's been a lot of talk lately, and you mentioned it before, about the cold plunge of taking a cold shower, putting your face in cold, cold ice water. That's just the opposite of what you're talking about. But they must be related somehow.

[Bill Gifford]

If you dig into the science, the data supporting cold plunging is actually quite a bit weaker than the data supporting this targeted heat exposure that I'm talking about. And so that's not to say that you shouldn't do it, but I think the expectation that cold plunging is a great thing to do after, like, a strength workout, I think, I think that's incorrect. There's a lot of research showing that jumping in cold water after you lift weights actually blunts your muscle growth. So you're blunting the benefits of the workout you just did.

[Mike Carruthers]

Well, I can't say I'm sorry to hear that. I'm not a big cold plunge guy. I'd rather be in a heated pool, frankly. I want to ask you about, like, so what do we do with this information about targeted heating? In just a moment, I'm speaking with Bill Gifford. He's author of the book Hot how the Hidden Power of Heat Makes Us Stronger. And so, Bill, I want to get a sense of, like, what's the prescription here? You've talked about the benefits of a sauna, but not everybody has access to one or is likely going to sit in a sauna every day or every other day. So what can you do?

[Bill Gifford]

I mean, you could just take a hot bath, too, honestly, like, if that's where you're at, the hot bath, again, has, has been found to have many of the same benefits as sauna, if not, if not greater. In fact, what about a hot shower? Not quite the same thing because you're not getting as much of a heat transfer to your, your body. You're just kind of sitting in the, in the sprinkling shower. But if you're actually immersed in the hot water in the tub, then you're getting your core temperatures going up and you're getting, you're getting those, those benefits of, of heat.

[Mike Carruthers]

You know, I think one of the things about sitting in a sauna is I've, I've never, I've been in a sauna once, but it's kind of boring. Like, there's not much to do.

[Bill Gifford]

There's this Interesting sort of cultural phenomenon that's kind of developed. I think it started in Germany, but they. They actually do these performances in a sauna. They'll have these sort of attractive performers come into the sauna and there'll be like 40 people in there, and they'll play music or they'll. They'll kind of dance around and they'll wave these towels, like blasting heat, moving the heat, the hot air around the room in your face. And like, it's very intense. And then that. That's called aufgoose. It's crazy. It's like a whole culture. There's. There's competitions, there's costumes, there's people. There are people who do, like, miniature plays and skits in the sauna. I once sat in a sauna and listened to a singer belt out an aria from the opera Tosca. And there wasn't a dry eye in the room, and we were all sweating, but, like, it was. It was powerful. And so that cures the boredom problem. So just.

[Mike Carruthers]

You could.

[Bill Gifford]

You're not just sitting there stewing in your own juices. You know, you've got something to sort of divert your attention, and

[Mike Carruthers]

you're making it sound so appealing.

[Bill Gifford]

It is very. It's very cool.

[Mike Carruthers]

Is there a benefit to. When you're done and you step out back into the cool. Like, is that. Is that a rush or is that. Is that not why people do it? That's more kind of like hitting yourself with a hammer and then stopping.

[Bill Gifford]

There's a little bit of the hitting yourself with the hammer thing. I won't lie. But there is a phenomenon. You almost get sauna drunk or sauna high. So if you go in to the hot room and then you either you cool off or you do a. A quick cold dip, you do that a few times. Many people have noticed. I noticed you get almost like sauna drunk. Like, you're. You're just a little bit euphoric. You know, you don't really care about the things that were bothering you before you went in. And honestly, I noticed that.

[Mike Carruthers]

Well, it's certainly interesting, but does modern medicine typically. Like, if you were to ask people in the medical profession, they would, oh, yeah, we know about that. Or is this all fairly new stuff?

[Bill Gifford]

You know, I think medicine is starting to take some notice of it. I mean, your doctor might not. Might or might not prescribe you sauna sessions, but one thing that I found that was really interesting is that what they call, again, whole body hyperthermia. Basically heating you up to a certain level is Being actively researched as a potential treatment against severe depression. And there have been some pretty striking results. For example, there is a study done initially in Germany by, you know, German and American researchers where they put people in these same devices that I talked about for that they use. Used to use for treating cancer patients. So they put very depressed people in these things, heated them up to 101Fahrenheit for an hour, which is, you know, not fun. I tried it myself. It's not fun. But then afterwards, their depression symptoms were cut in half and even more, which is way better than any antidepressant drug. Antidepressants only work in about 20 to 40% of patients. Even better, they went back a month later thinking that the antidepressant effect would have evaporated, would be gone, and they found that they were still not depressed, still less depressed, and again six weeks later. So it lasted six weeks. And so that got some attention. And then there are various studies happening right now, and other studies have come out since then kind of confirming this result, which is great news, I think.

[Mike Carruthers]

I would think one of the concerns, if you're using heat for the health benefits that it supposedly produces, that one of the concerns would be hydration, because heat, it will evaporate water and that you could get dehydrated from doing the kinds of things you're talking about.

[Bill Gifford]

You know, everybody walks around with a water bottle now everywhere, right? On the airplane, in a theater, in a restaurant. Everybody's got their sort of emotional support water bottles. And I was kind of shocked and amazed to discover that drinking too much over hydration. And again, this is related to heat in the sense that you need to hydrate to replace the water you lose from sweat, etc, over hydration can actually kill you or make you sick.

[Mike Carruthers]

So how does that work? Seems like you'd have to drink an awful lot of water for that to happen.

[Bill Gifford]

If you drink too much water, these mechanisms in your body that regulate your fluid level and your salinity and all this kind of stuff, you can essentially dilute your body to a situation called hyponatremia, which basically means you're not salty enough, you don't have enough sodium, so that your cell membranes and neurotransmitters and things like that kind of stop working. It's a very serious situation. It's relatively rare. But it happened to Brooke Shields about a year ago, year and a half ago, she nearly died. So we need to be careful around the hydration situation. But I think the big takeaway is that targeted limited exposure to heat can actually have some benefits in terms of our physical, mental, emotional health.

[Mike Carruthers]

Well, when I hear about heat, I think, well, that's something to avoid because heat can be dangerous and people get sick and die from exposure to heat. But I've never heard of all these health benefits you're talking about. And you're a well regarded writer that clearly has researched this. I find it fascinating. I've been talking to Bill Gifford. He is a veteran magazine writer and editor who covers cutting edge health research and he is author of a book, how the Hidden Power of Heat Makes Us Stronger. And there's a link to that book in the show notes. Bill, great. Thanks. Appreciate the info.

[Bill Gifford]

Thanks, Mike. This is great. I loved all your questions. This was great.

[Mike Carruthers]

It sounds too simple, but research shows that chewing gum can improve alertness and help you stay focused, especially during long or repetitive tasks. In studies, people who chewed gum perform better on tests of attention and reaction time, particularly as tasks went on and mental fatigue set in. Scientists think it works because chewing gum increases brain arousal and keeps you mentally engaged, almost like giving your brain something small to do so. It doesn't drift. There's even some evidence that mint flavors like peppermint may add a slight boost, possibly because they stimulate scent. But here's the catch. Chewing gum won't make you smarter or better at complex thinking. What it can do is help you stay in the zone longer. So if your focus starts to slip, you might not need more coffee. You might just need a stick of gum. And that is something you should know. This program is produced by Jennifer Brennan and Jeff Havison. Executive producer is Ken Williams. I'm Mike Carruthers. Thanks for listening today to something you should know.

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[Vulgar History Podcast Host]

Ah, the Regency era. You might know it as the time when Bridgerton takes place or the time when Jane Austen wrote her books. But the Regency era was also an explosive time of social change, sex scandals, and maybe the worst king in British history. And on the Vulgar History podcast, we're going to be looking at the balls, the gowns, and all the scandal of the Regency era. Vulgar History is a women's history podcast, and our Regency Era series will be focusing on the most rebellious women of this time. That includes Jane Austen herself, who is maybe more radical than you might have thought. We'll also be talking about queer icons like Anne Lister, scientists like Mary Anning and Ada Lovelace, as well as other scandalous actresses, royal mistresses, rebellious princesses, and other lesser known figures who made history happen in England in the Regency era. Listen to Vulgar History wherever you get podcasts.