in: Health, Health & Fitness

• Last updated: October 1, 2021

Podcast #638: How Changing Your Breathing Can Change Your Life

When we think about improving our health, we typically think about altering our diet, trying to exercise more, and taking vitamins and supplements. But my guest today argues that none of that stuff really matters if we haven’t improved something even more foundational: our breathing.

His name is James Nestor and his latest book is Breath: The New Science of a Lost Art. At the beginning of our conversation, James explains why he paid thousands of dollars to have his nose plugged up, and what happened to his body when he could only breathe out of his mouth. We unpack the dangers of the common problem of being a habitual mouth breather, including the fact that it can even change the shape of our faces, and why modern humans started breathing through the mouth rather than the nose. James then reveals what happened when he switched his experiment around and breathed only through his nose, and explains why simply switching the passageway of your breathing from oral to nasal can have such significant health benefits. He also shares his weird trick to switch from mouth to nose breathing at night, which I’ve tried myself and found effective. We then discuss the importance of getting better at exhaling, and why you counterintuitively probably need to be thinking more about getting carbon dioxide into your body rather than oxygen. In the latter part of our conversation, we discuss more advanced breathing techniques, including hypoventilation training, where you double your exhales to inhales to acclimate yourself to higher levels of CO2, as well as other experimental breathing techniques that may allow people to take conscious control of the supposedly involuntary autonomic nervous system in order to boost immunity and heal diseases. 

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Show Highlights

  • How James got interested in the science of breathing
  • The crazy experiment James did with mouth-breathing
  • Why are modern people mouth-breathers?
  • Why have our mouths gotten smaller?
  • What happened when James went back to nose-breathing
  • Why mouth-breathing at night is so bad for you (and how to stop doing it) 
  • The importance of the exhale 
  • Hypoventilation training 
  • The important role of carbon dioxide in our breathing 
  • Can we reverse damage that’s already been done?
  • Toning the tongue to increase airway health 
  • The extraordinary fringes of breath science 
  • Why does breathing have so much control over our automatic bodily functions/systems?
  • James’ experience with these wild breath practices 
  • How breathing can help anxiety and depression 

Resources/People/Articles Mentioned in Podcast

breath by james nestor book cover.

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James on Instagram

James on Twitter

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Read the Transcript

Brett McKay: Brett McKay here, and welcome to another edition of The Art of Manliness podcast. And when we think about improving our health, we typically think about diet, trying to exercise more, taking vitamins and supplements, my guest today argues that none of that stuff really matters if we haven’t improved something even more foundational, our breathing. His name is James Nestor, and his latest book is Breath: The New Science of a Lost Art. At the beginning of our conversation, James explains why he paid thousands of dollars to have his nose plugged up and what happened to his body when he could only breathe out of his mouth. We unpack the dangers of the common problem of being a habitual mouth breather, including the fact that it can even change the shape of our faces and why modern humans started breathing through their mouth rather than their nose in the first place.

James then reveals what happened when he switched his experiment around and breathe only through his nose and he explains why simply switching the passageway of your breathing from oral to nasal can have such significant health benefits. He also shares this weird trick to switch from mouth to nose breathing at night, which I’ve tried myself and I’ve found effective. We then discussed the importance of getting better at exhaling and why you can intuitively probably need to be thinking more about, getting more carbon dioxide in your body rather than oxygen. In the latter part of our conversation, we discuss more advanced breathing techniques, including hypoventilation training, where you double your exhale to inhales to acclimate yourself to higher levels of CO2, as well as other experimental breathing techniques that may allow people to take conscious control of the supposedly involuntary autonomic nervous system in order to boost immunity and heal diseases. After the show is over, check out our show notes at

Alright, James Nestor, welcome back to the show.

James Nestor: Thanks so much for having me.

Brett McKay: So we had you on a couple of years ago to talk about your book Deep, which is about free divers, and these are people who trained themselves to, without any aid of oxygen, to just go down as far as they can in the ocean, and they’re down there for minutes at a time, and you were talking about the science of this. While you were researching this book and doing this, you were yourself were dealing with some breathing problems. What were the type of problems you were struggling with, and what made you think, “Well, maybe if these free divers could train themselves to breathe better, maybe I can do that too”?

James Nestor: I had been surfing a lot at Ocean Beach and exercising a bunch and thought that just chronic bronchitis was just part of the game, because everyone I knew was having some sort of respiratory problem or another, be it allergies, asthma, bronchitis on occasion, I was getting mild pneumonia year after year, it wasn’t any big deal, I’d just take antibiotics and be on with it. And again, I didn’t expect that anything was wrong until I saw my doctor and she was like, “Hey, I think you’re not breathing properly, and it could be exacerbating or maybe even causing these problems.” So she suggested I go to a breathing class, and I did that. I had this very weird experience, just sitting there, in the corner of this cold room here in San Francisco, breathing in this rhythmic pattern, and I sweated through my t-shirt, my hair was sopping wet, there were sweat stains on my jeans. It was completely wild, unlike anything I had experienced, and I thought, “Wow, something’s going on here. I wonder what the science has to say about this.” And so that was really, beyond free diving, where I saw the potential of breathing, for underwater research, I also started wondering what breathing could do for the rest of us on land. And that’s what really set me off.

Brett McKay: And it set you off on a new book. You went on all these crazy scientific adventures, and the first one is the craziest, because you basically you paid $5000 to have a doctor plug up your nose. What were you hoping to learn by doing that?

James Nestor: Yeah, this was never intended. So this was never ever part of my plan. It’s funny, people read the book and they think that I had placed myself in these situations on purpose, but it was through total happenstance. The doctor, he’s the Chief of Rhinology Research at Stanford, so knows everything about the nose. And I had had several interviews with him, long, hours long interviews, and he kept telling me about all the wondrous things the nose can do. How it can help fight off viruses, how it conditions air, how it allows us to absorb more oxygen. And he kept also telling me about how bad it was that so many of us are breathing through our mouths. Something like 25% to 50% of us are chronic mouth breathers, and I think I was breathing through my mouth a lot too, ’cause I didn’t know the difference. And so I asked him, I said, “Well, how soon does this damage from mouth breathing come on?” That includes neurological problems, it includes respiratory problems, poor athletic performance, all of that. And that’s been known for a while, but nobody really knew how quickly it came on. And he didn’t know, no one had conducted an experiment with it, so I volunteered for an experiment. Of course, Stanford didn’t have money for this kind of research. So we had to pony up the cash ourselves, and it was even more than five grand, so I used a big chunk of my book advance to do this because I was curious to see what would happen.

Brett McKay: So basically, he stuck plugs up your nose, and then taped it, bet you couldn’t breathe through your nose. How soon did you start noticing changes in your breathing and how it had influenced your health?

James Nestor: Yeah, so that was the plan, it was for 10 days, silicon up the nose, tape over that, to inhibit even the slightest amount of air entering the nose. So me and one other subject, a breathing therapist named Anders Olsson, we were only mouth breathing for 10 days and we were recording what was happening in our brains, physiological data three times a day, every single day, and we found that mouth breathing… We knew it was bad, we didn’t know it was gonna be this bad. Within a few hours, my… This is a few hours of switching our breathing. My blood pressure shot up about 20 points. That night, my snoring increased 1300%. Within three days, I was snoring through half the night, I hadn’t been snoring before doing this, Anders, the other subject in the experiment suffered the exact same damage. We were stressed, fatigued. I mean, you name it. And to me, this explained, at least partly, why so many people are suffering from so many of these chronic problems. It’s just switching the pathway of your breathing, just breathing through the mouth can really exacerbate so many issues.

Brett McKay: Alright, so you did this scientific experiment to get data on how bad mouth breathing is for you, but it was something that earlier cultures already knew intuitively. For example, you talk about tribes where the parents would close their baby’s lips with their fingers to keep them from breathing with their mouths.

James Nestor: Yeah, you can trace this back several thousand years, actually, in many early Hindu texts, they were talking about the wonders of nasal breathing, the Chinese wrote seven books of the Dao dedicated to breathing of all the bad things that can happen when you do it improperly. They specifically mention mouth breathing, how injurious it is for the body, and they talk about the wonders of nasal breathing, so this spread out through other cultures, and what was interesting to me is you can find this in cultures, but these cultures didn’t have direct contact with one another, so they all came to the same conclusions somewhat independently, and the Native Americans, that’s the story you’re citing, were habitual nasal breathers and they were so into it that some of them, according to the sources, would hesitate when they laughed because they didn’t wanna open their mouth for even a moment to get air in, and when they had infants after they were done breastfeeding, they would softly close their lips, they’d stand over them at night to see if they opened their mouths, while they were sleeping and softly closed their lips to make this a habit. Later on in life, to always breathe through the nose.

Brett McKay: Alright, so if mouth breathing is so bad for you, why do you modern people do it?

James Nestor: Well, I think we’ve become… It’s become so normal that you look at people running, you look at people in the gym, when we used to go to gyms and almost everyone’s breathing through their mouth, they’re thinking that more oxygen is gonna get into their bodies the more they breathe through their mouth, but the opposite is happening, this is such a counter-intuitive concept, took me months to get my head around, but I had thought it was habitual, I thought it was environmental our noses get plugged from pollutants or allergies or whatever, we have to breathe through our mouth, but it wasn’t until I dug deeper into the story and found it’s actually caused by evolution of the human skull, that seems nuts, but all you need to do is look at skulls from 400 years ago and look at skulls now, and they’ve massively changed, especially in the mouth, our mouths have grown so small, our teeth no longer fit, which is why they’re growing crooked, and the other problem with having a too small mouth, is you have a smaller airway, which is one of the main reasons so many of us have sleep apnea, snoring, other respiratory issues.

Brett McKay: Well, and you actually, you go to a crypt beneath Paris to look at, to find skulls from 400 years ago. So what would happen? Why have our mouths gotten smaller over the years.

James Nestor: Yeah, so that was one of the first expeditions I really did because I wasn’t able to get into labs, it’s hard to get into labs and look at ancient skills, I had not met the biological anthropologist that I later ended up working with. So I wanted to see what happened to our skulls up close and personal, and I managed to contact a friend of a friend who took me down to the quarries in Paris, which are about 60 feet below the streets of Paris, 170 miles and there’s six million human skulls down there. So I was able to root around and look at skulls down there without anyone looking over my shoulder, without any plaques or cautionary ropes, a completely wild experience. So what I learned later after that was that so much of the damage that’s been caused to our mouths, to our sinuses, to our ability to breathe, is because humans have stopped chewing. If you look at industrialized food, processed flour, processed rice, canned stuff, it’s all soft and without that masticatory stress, especially early in life, mouths don’t grow properly, they don’t grow wide enough, which is the main reason. There’s other things that contribute to this, but that’s the main reason so many of us have crooked teeth, and that is also correlated to breathing problems.

Brett McKay: Alright, kinda to add some context here, people have smaller mouths today because they have less exercise chewing on harder food, and that began even before the Industrial Revolution with industrialized food, it started with the dawn of cooking, so mouths have gotten taller rather than wider. And your nasal cavity, your sinuses get smaller as a result, which leads to a preference for mouth breathing, and it gets more interesting still because being mouth breather can actually change the shape of your face too.

James Nestor: Yeah, it’s so common that it has a official name, it’s called adenoid face, when kids get inflamed adenoids or tonsils, they have to breath through their mouth, and if you do this for so many years, it can actually change the skullicature of your face and it changes how you’re gonna look… Which is later on in life, these people who study this stuff, the scientists can tell if someone has been breathing through their mouth, through their youth, because of the way in which their face has grown, and what that means is it’s a longer face, it’s a droopier face, the chin is recessed, so you don’t have this big powerful chin, of course, genes and genetics determine a lot of how you’re gonna look, but epigenetics, these environmental inputs also have a huge influence of how you’re gonna grow and your health, including your breathing.

Brett McKay: So what happened? You did this experiment 10 days, what it was like to be a chronic mouth breather? What happened when you removed the nasal plugs and could breathe through your nose again?

James Nestor: Yeah, so the experiment was never intended to be like some Jackass stunt, we were lolling our bodies into a position they already knew, and that so much of the population already knew, the difference was we were calculating everything that was happening, so the good part of the experiment was that the next phase was only nasal breathing, I’m sure we snuck in some mouth breaths here and there, but the vast majority of the breaths we were taking per day, including all of those at night were through the nose, we also practiced some breathing techniques along the way and within the first night, my snoring almost completely disappeared, went down to about 30 minutes, three nights later… Two nights later, it was gone, I had no sleep apnea, no snoring, blood pressure went down about 20 points, 30 points from its highest point, the previous week. I mean, just a complete transformation, our athletic endurance increased, we were measuring that heart rate variability went through the roof, it was so dramatic, and yet this is such a simple thing to do, to breathe through the nose and not the mouth, and it seems to be completely lost on modern society.

Brett McKay: So what is it about nasal breathing, like you said, that we actually get more oxygen from breathing through our nose than our mouth, it doesn’t make sense, ’cause you’re like, Well, if I’m breathing through my mouth, I’m getting more air in. What’s going on in our nose that allows our body to get more oxygen?

James Nestor: Sure, so number of things are happening, first of all, you’re pressurizing the air and you’re slowing it down, which allows more time for oxygen to soak in, for gas exchange in your lungs. If you take a breath through your nose, you get that negative pressure going in that vacuum, then as you exhale through the nose, you get that positive pressure, so beyond just that, and you get 20% more oxygen equivalent breaths through the nose than through the mouth. That is enormous especially throughout the day, so other things are happening with that pressure, you’re able to push those soft tissues at the back of the airway further back and to help tone them a little more which opens the airway. If you open your mouth right now, I just learned this trick from Dr. Steven Park at Albert Einstein Medical Center, if you open your mouth right now, you’re gonna feel your tongue softly going back into your airway.

And then as you close your mouth, the tongue is gonna gently move up towards the upper palate. When it moves up towards the upper palate, you’re opening your airway which is also one of the reasons why nasal breathing is so effective for people with mild or even moderate snoring and sometimes even sleep apnea, so beyond that, it’s… The nose is the first line of defense, it filters stuff out, produces nitric oxide which interacts directly with viruses. There’s innumerable benefits to nasal breathing, and none of that is controversial, right? You ask anyone, any rhinologist and they know about this stuff, it’s just seldom practiced.

Brett McKay: To me it sounds like… Something I think people typically breathe through their mouth are thinking, “well, I got the sinus infection, so I can’t breathe through my nose,” but it sounds like the mouth breathing could be contributing to the sinus infection and your inability to breathe through your nose.

James Nestor: Absolutely, it’s a use it or lose it thing, and they’ve found this. The doctor of speech-language pathology down at Stanford studied people who had had laryngectomies, little holes drilled in their throat because they had mouth cancer or some other problem, and from two months to two years, their noses were 100% blocked, so zero could get in there. And she found that the more we use our nose, the more of those tissues are gonna become acclimated and open up and allow us to use our noses. So with something like chronic sinusitis, which 25% of the population suffers from this, that is a huge number, you gotta find a way of clearing your nose. As an IAC down at Stanford said if your toilet is plugged, you’re gonna find a way of clearing it and the nose has to be considered the same thing.

Brett McKay: So I think during the day, if someone can practice… Intentionally practice nose breathing, but what about at night? Right, and that’s another thing with mouth breathing at night, that’s one of the things that leads to bad breath, periodontal disease as well, so what can you do to make sure your mouth is shut at night?

James Nestor: So, so many other issues as well because when you’re breathing through the mouth, you don’t have all those structures in the nose that help to humidity and filter and condition air, so breathing through the mouth will release 40% more moisture than breathing through the nose. So I had been a mouth breather at night for as long as I can remember which is why I would go to bed with a huge glass of water by the bedside every single night, it didn’t matter if I was in a hotel and I just thought this was normal to be waking up with a dry mouth, hitting down water, going back to sleep, waking up, hitting down water, going back to sleep. It’s not normal. Sleeping with your mouth open is not a normal thing, you look at animals in the wild, they’re not doing it.

So what I had learned at Stanford, from Dr. Ann Kearney and also from Dr. Mark Burhenne is that we can use a teeny piece of tape, now I’m not talking about a fat strip of industrial tape or duct tape or anything, a teeny piece about the size of a postage stamp and you place that at the center of your lips and the point of this isn’t to block air from the mouth, it’s just to train the mouth to be closed at night. And I started doing this and recording what happened with my sleep and an extraordinary benefit, more oxygenation, better sleep, longer sleep, less resistance in the airway ’cause your mouth is closed. And since this book has come out which has been a couple of months, I’ve received literally dozens and dozens and dozens of emails from people saying, “Oh my God, why didn’t I know about this before?” They’re no longer snoring. Even people with mild or sleep apnea no longer have sleep apnea just by shutting their mouths.

Brett McKay: I did the mouth tape thing and I liked it, it worked, I slept pretty nicely. And that’s what I love about this book, it’s such a simple thing, just breathe through your nose and you can have all these benefits.

James Nestor: Sure, it’s one of the… That’s the foundation of healthy breathing that everyone needs to adhere to. It starts off with first, acknowledging that as a species we’re messed up, our faces are messed up, we become the worst breathers in the animal kingdom. The second is, and this is the… Most of the book, the foundation of the book is like, “Okay, we’re screwed up. What can we do to fix it?” And nasal breathing is the first thing.

Brett McKay: Another thing about breathing, and I think what most people think about breathing, they’re always thinking about the breath in part ’cause that feels nice, that your lungs are filling up, you feel like, “Oh. I’m getting oxygen.” But you highlight in research that the exhale is just as important, what happens in the exhale whenever we do exhale and what happens when we neglect that in our breathing?

James Nestor: So the only way to get a full nourishing breath in is to get that last breath out, to get that stale air out. A lot of us, when we first become aware of our breathing, we’re just putting air on top of air, on top of air, but air should be… Your breath could be considered like a cycle, it needs to cycle in, it needs to cycle out. And what Carl Stough found, and he was this choral conductor in the ’50s who found that few of his singers were really exhaling properly, they weren’t moving their diaphragms up high enough, and by just allowing them to engage more diaphragmatic movement, he completely changed the resonance, the volume of their voices and went on to teach opera singers or the Met opera this, but he then went on to… For 10 years, helped emphysemics by just increasing diaphragmatic movement. By just using breathing, he was able to effectively heal these people and have them walk out of the hospital, which is extraordinary but it also makes perfect sense. These people had lost the ability to breathe properly. Every single breath they took was a struggle and they were stressing themselves out every moment of every day.

Brett McKay: We’re gonna take a quick break for more words from our sponsors. And now back to the show. What do you do with the diaphragm to make sure all that air… How do you tell your diaphragm, “Squeeze that air out more?”

James Nestor: Sure. So breathing is this wonderful thing ’cause we do it unconsciously. We don’t have to be thinking about it. But we can also do it consciously. So if everyone just takes a big breath in now through the nose, please. As you breathe in your diaphragm, which is this muscle underneath the lungs. Because the lungs don’t do anything on themselves. They need something to expand them and contract them. That’s what the diaphragm does. So when you take that breath in, the diaphragm sinks. And when you exhale, the diaphragm lifts up a little higher into your chest. By increasing the movement of that diaphragm, there’s so many benefits to it. But especially considering breathing, it allows you access to more of your lungs. And by having access to more of your lungs, you can get in more air with fewer breaths. You can breathe more efficiently. Breathing is something a lot of us do 25,000 times a day. If you can do it more efficiently, you’re gonna have huge benefits from this as has been clearly studied and seen.

Brett McKay: One cue that I’ve used… I’ve heard to help you exhale is like to pretend like you’re holding your pee and for some reason that makes the diaphragm go up. That’s what I typically think. I’m holding my pee and then for some reason I’m able to get more air out.

James Nestor: I haven’t tried that one. I’m gonna add that to my list of activities here.

Brett McKay: Alright.

James Nestor: I do know that Carl Stough, the researcher who had done this and proven this. What he had patients do and this included Olympians. He was the guy who trained the 1968 track team, US track team to go down to Mexico City. They were the only team that did not use oxygen ’cause they didn’t need to, ’cause they were breathing properly and they destroyed everybody. It was like the greatest Olympic performance in track ever. And so he would have them start with that inhale and as they exhaled, he’d have them go, “One, two, three, four, five, six, seven, eight, nine, 10. One, two, three, four, five, six, seven, eight, nine, 10,” and count from 1-10. And even when they were out of breath to start whispering it. “One, two, three, four, five, six, seven, eight, nine, 10, One, two, three, four, five, six… ” And by doing that and vocalizing while you’re doing it, you’re able to engage more diaphragmatic movement.

Brett McKay: And what that also does, it lengthened your breath. And this kinda… Segway to my next question because this is one of the most counter intuitive things I got from your book. Like I said earlier, when we typically think of breathing, we think about the oxygen part. Oxygen is good, nourishes our bodies, gives us energy we need to do what we need to do. And then CO2, we wanna get rid of that because it’s waste. Right? But you have this interesting research that actually CO2 is an important part of our health and oxygen… Getting oxygen from breathing that’s not typically not a problem. It’s like we’re actually don’t have enough CO2 in our system. Can you walk us through this counter intuitive claim?

James Nestor: Sure. So a lot of people with chronic pathologies, people with emphysema, people with other issues can have not enough oxygen. Even with people with coronavirus. They don’t have enough O2. So what I was talking about and focusing on was ordinary, healthy people who don’t have these underlying conditions. And for healthy people, oxygen is seldom the problem. And you can see this by using a pulse oximeter and seeing that you have 95, 94 or even 97% oxygen in your bloodstream. That’s great. But what few people consider, and this blew my mind when I came across it, is that we need a balance of CO2 and oxygen in the body for oxygen to disassociate from hemoglobin, to feed our hungry cells. So CO2 is essential in this exchange and if we don’t have enough of it, our bodies have to compensate. And that compensation can start wearing us down. So when you see people again, out jogging, doing CrossFit or whatever or even sitting at an office in front of a computer and they’re breathing thinking, they’re getting more oxygen into their tissues and muscles and organs. The opposite is happening which is why their fingers are cold, which is why they get dizzy in their head. That feeling is caused by constriction. It’s when you offload too much CO2, you cause vasoconstriction throughout your body.

Brett McKay: And so I guess, what do you do to increase levels of CO2. It’s breathe less or breathe in less?

James Nestor: Yeah, breathe normally is the key and what that means for the vast majority of us, I’ve found, is to be breathing less and to be breathing slowly because in every breath, you’re offloading CO2. Right? And that’s good. We need to offload that CO2 and whatever toxins our bodies are purging through our lungs. Of course we need to do that. But what you wanna do is you don’t wanna offload too much of it. And so if we were to breathe 10 heavy breaths here, our CO2 levels are gonna go down and when they go down again, our bodies are forced to compensate for that. So by breathing slowly and breathing as closely in line with your metabolic needs, you’re able to use the most breath most efficiently. You’re able to do more with less and that’s the key to so much of health and fitness as well.

Brett McKay: But then you also… You can do these training things where you actually elevate CO2 and you said you did this run that sounded hellish. Where you would inhale for three seconds, exhale for four, inhale for three, and then make your exhale five. So basically, you were taking in less oxygen compared to… I try the just sitting still and I was like… I felt I was never getting a full breath. What were you hoping to accomplish by doing that?

James Nestor: So this is… This was the more extreme part of this, I would suggest people start with the mellower part and breathe… Breathe normally, breathe in line with your metabolic needs, which is lower and less, but what they’ve found is there are significant benefits to be had by controlling your breathing to a point. They call it hypo ventilation training. So it’s when you try to acclimate yourself to higher levels of CO2. And when you do this, when you’re out running… And again, I do not suggest anyone do this. Don’t do this in your car, do it with a breathing therapist. But when you’re out running, you try to double the exhales to the inhales, and immediately, you feel all of the circulation throughout your body, you start heating up… I mean, it gets almost psychedelic, ’cause what that is, is you are increasing circulation and oxygenation throughout your body when you’re doing this. You can get to a point where you’re breathing so little that your O2 is gonna go down, that’s for sure, but at the level we were doing it, our O2 wasn’t going down, our CO2 was going way up, and the… What triggers the need to breathe isn’t lack of oxygen, it’s an increase in CO2. So if you exhale right now and just hold your breath for 30 seconds or whatever, and you feel that need to breathe, that’s CO2, it’s not oxygen.

Brett McKay: Well, that’s what… We talked about that in Deep, right? Some of the training that free divers do, is they have to get their bodies comfortable with elevated CO2 levels.

James Nestor: Exactly. And so, so many of those benefits I was seeing this research sort of dovetailed together, it was blowing my mind to see the benefits of people who have trained with this hypo ventilation training, increasing their threshold of CO2, and they’ve found that the benefits of this are similar in many ways to altitude training. You can help build blood, you can pull more energy from lactic acid on and on, this guy, Xavier Warrens, in Paris, Paris 13 University, is now researching this stuff big time, and they’re actually using it for people with heart conditions. They’re using it because it helps people lose weight quicker, because it actually allows you to offload more oxygen and you burn fat with oxygen. So there’s… I included about 20 references to scientific studies looking at this stuff, and to me, it’s fascinating, just through breathing, you have access to all of these different systems in the body.

Brett McKay: I think you talked about, too, people with asthma, if they do the hypo ventilation, it can help with asthma as well.

James Nestor: It makes a huge difference with so many people, and again, I included, I think, 50 studies showing how slower breathing by breathing less can really help people with asthma. Asthmatics, as a population, tend to breathe way more than the rest of us, and they tend to breathe from their mouth, so they’re exposing themselves to everything, all the pollutants, allergen, whatever else in the environment, all the time, which can exacerbate their allergic reaction to asthma. If you think about someone with asthma, the last thing they wanna do is suffer another asthma attack, so they become so sensitized to CO2 that whenever they think they’re having an attack, what do they do? They breathe more and more and more, which causes more constriction, which… Guess what? Brings on an attack. So by teaching them to breathe normally… I call it breathing less, but it’s actually teaching them to just breath normally in line with their metabolic needs, they’ve shown huge benefits for people with asthma.

Brett McKay: And so just to recap here, the reason why elevated CO2 is necessary, or you need CO2, is that it’s what allows your body or your blood to… Or your body to take the oxygen off the blood cell and use it as part of it…

James Nestor: That’s right.

Brett McKay: Okay.

James Nestor: More efficiently.

Brett McKay: More efficiently, okay.

James Nestor: It allows your body to do this more efficiently, yes.

Brett McKay: Okay. So you mentioned earlier, our mouths are jacked up because of modern life. We eat soft foods, so our teeth are all… This affects breathing because it constricts the nasal passages as well, it makes our teeth growing crooked. And so this happens to kids, and that’s why they go to the orthodontist, they get palate expanders, braces, straighten that out. Is it possible to reverse this in adulthood? Can we make our mouths more like our ancestors? Or is it too late for us?

James Nestor: Well, the key, as with anything, is preventative maintenance, right? When you’re young, it’s so important to have proper habits to be closing your mouth, to not be mouth breathing at night, they’ve shown that breastfeeding versus bottle feeding is so beneficial to airway health, eating harder foods can… That masticatory stress can benefit mouth growth. But for me, youth was many decades ago, so I’m kinda hosed, and my mouth is… We took CAT scans of my sinuses and I’m as messed up as anyone. Deviated septum, clogging here and there, small mouth, I had braces, extractions, headgear, all that crap. So it turns out that we can change a lot of what we have in adulthood. First of all, we can tone the airway, we can do this through oral pharyngeal exercises, these tongue exercises. This sounds a little crazy, but it makes perfect sense. The tongue is a muscle, a very powerful muscle, when we don’t use it when we’re eating soft foods and we’re not using it properly, it can grow out of shape just like anything else, so by toning that tongue, you can increase your airway health, and that’s been widely shown, but you can also help expand your too small mouth, even in adulthood. If people are listening there and you have a clean thumb… Don’t do this if you’ve been touching door knobs or whatever. You can put your thumb on the top of your upper palate.

And right in the middle of that upper palate, there is a suture. And these are the same sutures that are in the skull. Now you can feel your skull and feel all these little ridges and cracks. So that suture can open at virtually any age, I think up into your 70s, which means the upper palate can be expanded at any age, when you expand that upper palate, you expand your airways. So I used this device called a Homeoblock just to see if these claims were true. And I wore this thing at night for a year, we took a CAT scan before and after. And I had huge benefits from this, my airway opened up, I think about 15, almost 20%, which is enormous. And I even built bone in my face, which we’ve been told is impossible. Bone mass only goes down once we’re in our 30s, we can model it in one bone, right in the middle of our faces. So and the CAT scan’s proved it.

Brett McKay: So yeah, that helped you expand the airways, and it helped you breathe better. That first section is amazing ’cause it’s just about basic things you can do to improve your breathing significantly. It’s breathe through your nose, breathe more slowly than you think you need to breathe, than you’re probably are breathing right now. And then in the second half of the book you talk… It’s called Breathing Plus, and you wanted to like explore like the fringes, this is like you’re going back to like your deep territory, right, the fringes of breathing. And you talk about some of these people who are doing some crazy stuff with breathing. One of these guys we’ve talked about on our podcast is Wim Hof. And he does a type of breathing that has allowed him to you know, he can warm up his body, it can he can cause his immune system to kill bacteria on demand. What kind of breathing is he doing? And where did he get this idea of this sort of breathing where you can basically take over involuntary aspects of your body?

James Nestor: So I wanted to start with in the book, start with the problem real quick and start with a foundation that anyone can benefit from, it doesn’t matter if you’re an elite athlete or an asthmatic or whatever, just as you mentioned, nasal breathing, exhaling, breathing slower, or breathing less, huge foundation of science supporting that. Not a lot of people are gonna disagree with it. But also, you hear stories about Wim Hof, you hear about things like holotropic breathwork, these breathing practices that require more effort, right? This isn’t just, “Oh, I’m gonna breathe through my nose,” like they require some concerted effort to do this stuff. But I was curious to see how far breathing could take us, what it could do to really heal ongoing chronic maladies, what it could do to move us up that next level of human potential. And what Wim, you know, everyone calls it Wim Hof Method but he’s been very clear that he didn’t invent any of this stuff.

His breathing method has been around for thousands of years, people have been super heating their bodies with this, the Bon Buddhist monks have been doing this for so long. And what they all have… So you can call it different things, Tummo, Wim Hof Method, pranayama. But they’re all doing the same things. They’re allowing you to control your breath. And when you control your breath, you can then take control of certain elements of your autonomic nervous system, which was supposed to have been according to Western medicine, beyond our control, that’s BS, we can absolutely control it.

When you start controlling that you can start controlling immune function, which is why these people, I’ve talked I talked to dozens of these people had autoimmune diseases, arthritis, psoriasis, diabetes, I mean, on and on and on. And once they started using these methods to breathe, they were able to either blunt these symptoms, or some of them claimed to have outright cured them. And they’ve measured their progress with real measurements, real science, and I just thought that this was fantastic and amazing. It seems too good to be true but look what Wim’s done. He’s been studying in labs all over the world right now. We’re just starting to crack this thing open, which is really exciting.

Brett McKay: Yes. You talked about this one guy. He was I think a Hindu monk, he came to the United States, in kind of one of those whirlwind tours, but he was doing crazy stuff, he was with breathing, he was able to control his heartbeat so it only beat once every 300 seconds. So like people thought he was dead, like the doctors thought he was dead, but he was actually still alive.

James Nestor: Yeah, this was on the outer fringes of breathing. I tried to find the best breather in history. And there are stories of these people, who can superheat their bodies for hours at a time, melt snow, melt wet sheets. And we know this is true. Herbert Benson at Harvard has studied these guys extensively. And anyone can look that up online and find those studies published in Nature, the most prestigious scientific journal in the world. So I think the best breather that I could find that there were some scientific foundation to was this guy Swami Rama, he grew up in the Himalayas in the ’70s, he came to the States to kind of show what he could do. And they studied him at the manager clinic, a navy physicist, studied him with all the latest instruments at that time. So this wasn’t, some new age dude in India, this was a real scientist. And they found that he could flutter his heartbeat at a rate of 300 beats per minute, for 30 seconds at a time. Apparently, he could do it for much longer than that, which would… It’s called atrial fibrillation, which would kill most of us. But he was able to do this on command.

Even more amazingly, he was able to shift the blood flow in his hand, about 11 degrees from his thumb to his finger. So one side was all gray, and the other side was all red with circulation. I mean, it goes on and on and on. And these measurements, these reports were published in the New York Times, they were measured very carefully by experts in the field and still people find it pretty hard to believe that anyone could have this control over their systems. But I think Wim is kind of the new reincarnation of Swami Rama, and he’s busting down what we thought was possible, time and time again.

Brett McKay: So we know it happens ’cause there’s data at the back, but like, do scientists know why breathing is the key to unlocking or controlling these automatic functions of our body.

James Nestor: Because breathing helps you control your nervous system function. If you were to inhale right now, and do a count of about three, and then exhale, to a count about 12, you’re gonna feel your heart rate go down, slower, and slower, and slower. That’s because you’re stimulating your parasympathetic response when you’re exhaling, and we know that when you’re in this rest and relaxation, parasympathetic response, you are increasing circulations to different organs in your body, you’re decreasing inflammation.

So, if you’re talking about how breathing is healing people, this is not some crazy placebo effect. This is physiological, this is the most basic medicine of how the body works, and how it can retain balance. What’s so great about it is it’s measurable. So to directly answer your question, so how can Wim sit in an ice bath for two hours and not have his core temperature go down? How can he not suffer from any damage to his limbs, or hypothermia, or frostbite, or anything? We still don’t know. And we still don’t know how the Bon Buddhist are able to do this either. And this is what I get in it too, at the end of the book, there are still mysteries to breath, as far as heating yourself up and keeping it sustained at that level, and I hope science is gonna be checking that out and discovering exactly how to do it and how it works, but I think it’s thrilling that we think we have everything figured out, we’re just on the cusp of understanding the true potential of breathing, right now.

Brett McKay: Did you try any of these advanced breathing techniques? And what was your experience with it?

James Nestor: I tried them all. Yeah, as a journalist, I wanna be able to write from the inside of these things. And there were several studies that didn’t make it into the book, we just didn’t have room. So I tried this one, Sudarshan Kriya, which is very similar to Wim Hof Method. I went to the University of California, San Francisco, Hypoxia Lab, and they hooked me up to all of these different measurements, catheters in my veins on a gurney, all of this crap, and I so completely freaked out the people doing this, doing this study, that… ‘Cause I was able to make my blood so alkaline, to about 7.68, which if they saw someone with blood like this, they would immediately put them into an ER, and say “This person is about to die.” But something amazing happens when you consciously will yourself into these states, they can be incredibly healing. They make you more flexible, they make you more resilient. So, holotropic, I did that. I do Wim Hof breathing. I keep calling it that, but is really Tummo, been around forever. I do that about three or four times a week, this has just become a part of my life. I’ve seen the science, I’ve seen the benefits in my own body, and it seems this stuff is free, it’s available to everyone, and I wanna take advantage of that.

Brett McKay: Well you also… You came to my hometown, Tulsa, to do… To breathe in CO2.

James Nestor: I didn’t know you lived in Tulsa.

Brett McKay: I live in Tulsa, yeah.

James Nestor: Yeah, Dr. Justin Feinstein is out there, doing some incredible NIH funded research, looking into the role of CO2 therapy for people with chronic anxiety, chronic fear-based problems. You see the amount of people with panic, I think it’s about 10%, chronic anxiety, I think is about a quarter of the population. That includes people with anorexia and other serious issues. They aren’t really being helped, we know that SSRIs, Prozac and all of that is not really that much more effective than placebos, even though people have been using them for 30 years, which is absolutely wild. So he is introducing CO2 into their bodies, and helping them to become more flexible and tolerant of it, so that they will be able to breathe more comfortably at a slower rate, and let their bodies heal themselves. And again, this is… He’s one of the top researchers in this field. This is NIH-funded research. I was able to go out there and go through a study, inhale CO2, and I think the results are gonna be published in a couple of years, it’s a very long research study.

Brett McKay: Sounds frightening, it feels like you’re suffocating, basically, but you’re not. He’s like, “No, you’re fine. You got plenty of oxygen. You’re gonna be okay.” And you feel like you’re drowning, but you’re okay.

James Nestor: Yeah, it sucked. I’m not gonna… I’m not gonna gloss over it. What happens is, when you’re introduced to this much CO2, and he gave me a double dose, just to be clear, far above what the other people… The other patients in the study were given. I said, “Go for it. I’ve never had a panic attack.” So what he was essentially doing was eliciting a panic attack in my body, so I was hooked up to all these instruments, and I was able to see on a computer monitor my oxygen didn’t change at all. It was steady the whole time. But he introduced this huge amount of CO2, and I felt… I experienced what a panic attack felt like, and I feel so sorry for these people now, because it lasts for a long time, sweating, everything becomes… Your vision becomes narrowed. It was awful, but the more acclimated to more CO2 you become, the easier that gets. So if I would have gone back and done that over and over again, as he does with his patients, that experience would have become lessened, and lessened, and lessened, the longer I did it.

Brett McKay: That’s super weird, but also hopeful. Well, James, this has been a great conversation, where can people go to learn more about the book and your work?

James Nestor: My website,, you can put a backslash breath in there, I put all scientific references there. There are free breathing videos from the experts in the field, FAQ, all that. I’m also trying to get better at the social media thing, a bit of a dinosaur, so on my Instagram page, I’m posting little videos and other pictures along this journey in new breathing research.

Brett McKay: Fantastic. Well, James Nestor, thanks for your time, it’s been a pleasure.

James Nestor: Thank you very much for having me.

Brett McKay: My guest here was James Nestor, he’s the author of the book Breath: The New Signs of a Lost Art. It’s available on and book stores everywhere. You can find out more information about his work at his website, Also check our shows at, where you’ll find links to resources and we delve deeper in this topic.

Well, that wraps up another edition of The AOM Podcast. Check at our website, where you can find our podcast archive, as well as thousands of articles. And if you’d like to enjoy ad-free episodes of the AOM podcast, you can do so on Stitcher Premium. Head to, sign up, use code MANLINESS at check out, for a free month trial. Or just sign up, download the Stitcher app on Android or iOS, and you start enjoying ad-free episodes of The AOM Podcast. And if you haven’t done so already, I’d appreciate if you to take one minute to give us a review in Apple Podcast or Stitcher. It helps out a lot, and if you’ve done that already, thank you. Please, consider sharing the show with a friend or family member who you think would get something out of it. As always, thank you for the continuous support. Until next time, this is Brett McKay, reminding you to not only listen to The AOM Podcast, but put what you’ve heard into action.

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