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Breath

The New Science of a Lost Art

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Ebook
On sale May 26, 2020 | 304 Pages | 9780735213630
A New York Times Bestseller

A Washington Post Notable Nonfiction Book of 2020

Named a Best Book of 2020 by NPR
 
“A fascinating scientific, cultural, spiritual and evolutionary history of the way humans breathe—and how we’ve all been doing it wrong for a long, long time.” —Elizabeth Gilbert, author of Big Magic and Eat Pray Love

No matter what you eat, how much you exercise, how skinny or young or wise you are, none of it matters if you’re not breathing properly.


There is nothing more essential to our health and well-being than breathing: take air in, let it out, repeat twenty-five thousand times a day. Yet, as a species, humans have lost the ability to breathe correctly, with grave consequences.

Journalist James Nestor travels the world to figure out what went wrong and how to fix it. The answers aren’t found in pulmonology labs, as we might expect, but in the muddy digs of ancient burial sites, secret Soviet facilities, New Jersey choir schools, and the smoggy streets of São Paulo. Nestor tracks down men and women exploring the hidden science behind ancient breathing practices like Pranayama, Sudarshan Kriya, and Tummo and teams up with pulmonary tinkerers to scientifically test long-held beliefs about how we breathe.

Modern research is showing us that making even slight adjustments to the way we inhale and exhale can jump-start athletic performance; rejuvenate internal organs; halt snoring, asthma, and autoimmune disease; and even straighten scoliotic spines. None of this should be possible, and yet it is.

Drawing on thousands of years of medical texts and recent cutting-edge studies in pulmonology, psychology, biochemistry, and human physiology, Breath turns the conventional wisdom of what we thought we knew about our most basic biological function on its head. You will never breathe the same again.

One

 

The Worst Breathers in the Animal Kingdom

 

The patient arrived, pale and torpid, at 9:32 a.m. Male, middle-aged, 175 pounds. Talkative and friendly but visibly anxious. Pain: none. Fatigue: a little. Level of anxiety: moderate. Fears about progression and future symptoms: high.

 

Patient reported that he was raised in a modern suburban environment, bottle-fed at six months, and weaned onto jarred commercial foods. The lack of chewing associated with this soft diet stunted bone development in his dental arches and sinus cavity, leading to chronic nasal congestion.

 

By age 15, patient was subsisting on even softer, highly processed foods consisting mostly of white bread, sweetened fruit juices, canned vegetables, Steak-umms, Velveeta sandwiches, microwave taquitos, Hostess Sno Balls, and Reggie! bars. His mouth had become so underdeveloped it could not accommodate 32 permanent teeth; incisors and canines grew in crooked, requiring extractions, braces, retainers, and headgear to straighten. Three years of orthodontics made his small mouth even smaller, so his tongue no longer properly fit between his teeth. When he stuck it out, which he did often, visible imprints laced its sides, a precursor to snoring.

 

At 17, four impacted wisdom teeth were removed, which further decreased the size of his mouth while increasing his chances of developing the chronic nocturnal choking known as sleep apnea. As he aged into his 20s and 30s, his breathing became more labored and dysfunctional and his airways became more obstructed. His face would continue a vertical growth pattern that led to sagging eyes, doughy cheeks, a sloping forehead, and a protruding nose.

 

This atrophied, underdeveloped mouth, throat, and skull, unfortunately, belongs to me.

 

I'm lying on the examination chair in the Stanford Department of Otolaryngology Head and Neck Surgery Center looking at myself, looking into myself. For the past several minutes, Dr. Jayakar Nayak, a nasal and sinus surgeon, has been gingerly coaxing an endoscope camera through my right nasal cavity. He's gone so deep into my head that it's come out the other side, into my throat.

 

"Say eeee," he says. Nayak has a halo of black hair, square glasses, cushioned running shoes, and a white coat. But I'm not looking at his clothes, or his face. I'm wearing a pair of video goggles that are streaming a live feed of the journey through the rolling dunes, swampy marshes, and stalactites inside my severely damaged sinuses. I'm trying not to cough or choke or gag as that endoscope squirms a little farther down.

 

"Say eeee," Nayak repeats. I say it and watch as the soft tissue around my larynx, pink and fleshy and coated in slime, opens and closes like a stop-motion Georgia O'Keeffe flower.

 

This isn't a pleasure cruise. Twenty-five sextillion molecules (that's 250 with 20 zeros after it) take this same voyage 18 times a minute, 25,000 times a day. I've come here to see, feel, and learn where all this air is supposed to enter our bodies. And I've come to say goodbye to my nose for the next ten days.

 

For the past century, the prevailing belief in Western medicine was that the nose was more or less an ancillary organ. We should breathe out of it if we can, the thinking went, but if not, no problem. That's what the mouth is for.

 

Many doctors, researchers, and scientists still support this position. Breathing tubes, mouthbreathing, and nasal breathing are all just means to the same end. There are 27 departments at the National Institute of Health devoted to lungs, eyes, skin disease, ears, and so on. The nose and sinuses aren't represented in any of them.

 

Nayak finds this absurd. He is the chief of rhinology research at Stanford. He heads an internationally renowned laboratory focused entirely on understanding the hidden power of the nose. He's found that those dunes, stalactites, and marshes inside the human head orchestrate a multitude of functions for the body. Vital functions. "Those structures are in there for a reason!" he told me earlier. Nayak has a special reverence for the nose, which he believes is greatly misunderstood and underappreciated. Which is why he's so interested to see what happens to a body that functions without one. Which is what brought me here.

 

Starting today, I'll spend the next quarter of a million breaths with silicone plugs blocking my nostrils and surgical tape over the plugs to stop even the faintest amount of air from entering or exiting my nose. I'll breathe only through my mouth, a heinous experiment that will be exhausting and miserable, but has a clear point.

 

Forty percent of today's population suffers from chronic nasal obstruction, and around half of us are habitual mouthbreathers, with females and children suffering the most. The causes are many: dry air to stress, inflammation to allergies, pollution to pharmaceuticals. But much of the blame, I'll soon learn, can be placed on the ever-shrinking real estate in the front of the human skull.

 

When mouths don't grow wide enough, the roof of the mouth tends to rise up instead of out, forming what's called a V-shape or high-arched palate. The upward growth impedes the development of the nasal cavity, shrinking it and disrupting the delicate structures in the nose. The reduced nasal space leads to obstruction and inhibits airflow. Overall, humans have the sad distinction of being the most plugged-up species on Earth.

 

I should know. Before probing my nasal cavities, Nayak took an X-ray of my head, which provided a deli-slicer view of every nook and cranny in my mouth, sinuses, and upper airways.

 

"You've got some . . . stuff," he said. Not only did I have a V-shape palate, I also had "severe" obstruction to the left nostril caused by a "severely" deviated septum. My sinuses were also riddled with a profusion of deformities called concha bullosa. "Super uncommon," said Nayak. It was a phrase nobody wants to hear from a doctor.

 

My airways were such a mess that Nayak was amazed I hadn't suffered from even more of the infections and respiration problems I'd known as a kid. But he was reasonably certain I could expect some degree of serious breathing problems in the future.

 

Over the next ten days of forced mouthbreathing, I'll be putting myself inside a kind of mucousy crystal ball, amplifying and hastening the deleterious effects on my breathing and my health, which will keep getting worse as I get older. I'll be lulling my body into a state it already knows, that half the population knows, only multiplying it many times.

 

"OK, hold steady," Nayak says. He grabs a steel needle with a wire brush at the end. It's the size of a mascara brush. I'm thinking, He's not going to put that thing up my nose. A few seconds later, he puts that up my nose.

 

I watch through the video goggles as Nayak maneuvers the brush deeper. He keeps sliding until the brush is no longer up my nose, no longer playing around my nose hair, but wiggling inside of my head a few inches deep. "Steady, steady," he says.

 

When the nasal cavity gets congested, airflow decreases and bacteria flourish. These bacteria replicate and can lead to infections and colds and more congestion. Congestion begets congestion, which gives us no other option but to habitually breathe from the mouth. Nobody knows how soon this damage occurs. Nobody knows how quickly bacteria accumulate in an obstructed nasal cavity. Nayak needs to grab a culture of my deep nasal tissue to find out.

 

I wince as I watch him twist the brush deeper still, then spin it, skimming off a layer of gunk. The nerves this far up the nose are designed to feel the subtle flow of air and slight modulations in air temperature, not steel brushes. Even though he's dabbed an anesthetic in there, I can still feel it. My brain has a hard time knowing exactly what to do, how to react. It's difficult to explain, but it feels like someone is needling a conjoined twin that exists somewhere outside of my own head.

 

"The things you never thought you'd be doing with your life," Nayak laughs, putting the bleeding tip of the brush into a test tube. He'll compare the 200,000 cells from my sinuses with another sample ten days from now to see how nasal obstruction affects bacterial growth. He shakes the test tube, hands it to his assistant, and politely asks me to take the video goggles off and make room for his next patient.

 

Patient #2 is leaning against the window and snapping photos with his phone. He's 49 years old, deeply tanned with white hair and Smurf-blue eyes, and he's wearing spotless beige jeans and leather loafers without socks. His name is Anders Olsson, and he's flown 5,000 miles from Stockholm, Sweden. Along with me, he's ponied up more than $5,000 to join the experiment.

 

I'd interviewed Olsson several months ago after coming across his website. It had all the red flags of flakiness: stock images of blond women striking hero poses on mountaintops, neon colors, frantic use of exclamation points, and bubble fonts. But Olsson wasn't some fringe character. He'd spent ten years collecting and conducting serious scientific research. He'd written dozens of posts and self-published a book explaining breathing from the subatomic level on up, all annotated with hundreds of studies. He'd also become one of Scandinavia's most respected and popular breathing therapists, helping to heal thousands of patients through the subtle power of healthy breathing.

 

When I mentioned during one of our Skype conversations that I would be mouthbreathing for ten days during an experiment, he cringed. When I asked if he wanted to join in, he refused. "I do not want to," he declared. "But I am curious."

 

Now, months later, Olsson plops his jet-lagged body into the examination chair, puts on the video glasses, and inhales one of his last nasal breaths for the next 240 hours. Beside him, Nayak twirls the stainless-steel endoscope the way a heavy metal drummer handles a drumstick. "OK, lean your head back," says Nayak. A twist of the wrist, a crane of the neck, and he goes deep.

 

The experiment is set up in two phases. Phase I consists of plugging our noses and attempting to live our everyday lives. We'll eat, exercise, and sleep as usual, only we'll do it while breathing only through our mouths. In Phase II, we'll eat, drink, exercise, and sleep like we did during Phase I, but we'll switch the pathway and breathe through our noses and practice a number of breathing techniques throughout the day.

 

Between phases we'll return to Stanford and repeat all the tests we've just taken: blood gases, inflammatory markers, hormone levels, smell, rhinometry, pulmonary function, and more. Nayak will compare data sets and see what, if anything, changed in our brains and bodies as we shifted our style of breathing.

 

I'd gotten a fair share of gasps from friends when I told them about the experiment. "Don't do it!" a few yoga devotees warned. But most people just shrugged. "I haven't breathed out of my nose in a decade," said a friend who had suffered allergies most of his life. Everyone else said the equivalent of: What's the big deal? Breathing is breathing.

 

Is it? Olsson and I will spend the next 20 days finding out.

 

. . .

 

A while back, some 4 billion years ago, our earliest ancestors appeared on some rocks. We were small then, a microscopic ball of sludge. And we were hungry. We needed energy to live and proliferate. So we found a way to eat air.

 

The atmosphere was mostly carbon dioxide then, not the best fuel, but it worked well enough. These early versions of us learned to take this gas in, break it down, and spit out what was left: oxygen. For the next billion years, the primordial goo kept doing this, eating more gas, making more sludge, and excreting more oxygen.

 

Then, around two and a half billion years ago, there was enough oxygen waste in the atmosphere that a scavenger ancestor emerged to make use of it. It learned to gulp in all that leftover oxygen and excrete carbon dioxide: the first cycle of aerobic life.

 

Oxygen, it turned out, produced 16 times more energy than carbon dioxide. Aerobic life forms used this boost to evolve, to leave the sludge-covered rocks behind and grow larger and more complex. They crawled up to land, dove deep into the sea, and flew into the air. They became plants, trees, birds, bees, and the earliest mammals.

 

Mammals grew noses to warm and purify the air, throats to guide air into lungs, and a network of sacs that would remove oxygen from the atmosphere and transfer it into the blood. The aerobic cells that once clung to swampy rocks so many eons ago now made up the tissues in mammalian bodies. These cells took oxygen from our blood and returned carbon dioxide, which traveled back through the veins, through the lungs, and into the atmosphere: the process of breathing.

 

The ability to breathe so efficiently in a wide variety of ways-consciously and unconsciously; fast, slow, and not at all-allowed our mammal ancestors to catch prey, escape predators, and adapt to different environments.

 

It was all going so well until about 1.5 million years ago, when the pathways through which we took in and exhaled air began to shift and fissure. It was a shift that, much later in history, would affect the breathing of every person on Earth.

 

I'd been feeling these cracks for much of my life, and chances are you have, too: stuffy noses, snoring, some degree of wheezing, asthma, allergies, and the rest. I'd always thought they were a normal part of being human. Nearly everyone I knew suffered from one problem or another.

 

But I came to learn that these problems didn't randomly develop. Something caused them. And the answers could be found in a common and homely human trait.

 

 

A few months before the Stanford experiment, I flew to Philadelphia to visit Dr. Marianna Evans, an orthodontist and dental researcher whoÕd spent the last several years looking into the mouths of human skulls, both ancient and modern. We were standing in the basement of the University of Pennsylvania Museum of Archaeology and Anthropology, surrounded by several hundred specimens. Each was engraved with letters and numbers and stamped with its ÒraceÓ: Bedouin, Copt, Arab of Egypt, Negro Born in Africa. There were Brazilian prostitutes, Arab slaves, and Persian prisoners. The most famous specimen, I was told, came from an Irish prisoner whoÕd been hanged in 1824 for killing and eating fellow convicts.

 

The skulls ranged from 200 to thousands of years old. They were part of the Morton Collection, named after a racist scientist named Samuel Morton, who, starting in the 1830s, collected skeletons in a failed attempt to prove the superiority of the Caucasian race. The only positive outcome of Morton's work is the skulls he spent two decades gathering, which now provide a snapshot of how people used to look and breathe.

James Nestor is an author and journalist who has written for Scientific American, Outside, The New York Times, The Atlantic, and more. His latest book, Breath: The New Science of a Lost Art, was an instant New York Times and London Sunday Times bestseller and will be translated into more than 35 languages. Breath was awarded the Best General Nonfiction Book of 2020 by the American Society of Journalists and Authors and was a Finalist for Best Science Book of 2021 by the Royal Society. Nestor’s first book, Deep: Freediving, Renegade Science, and What the Ocean Tells Us About Ourselves, was a Finalist for the 2014 PEN/ESPN Award For Literary Sports Writing and an Amazon Best Science Book of 2014. Nestor has presented his work at Stanford Medical School, the United Nations, and on radio and television shows including Fresh Air with Terry Gross, ABC’s Nightline, CBS Morning News, and dozens of NPR programs. He lives and breathes in San Francisco. View titles by James Nestor

About

A New York Times Bestseller

A Washington Post Notable Nonfiction Book of 2020

Named a Best Book of 2020 by NPR
 
“A fascinating scientific, cultural, spiritual and evolutionary history of the way humans breathe—and how we’ve all been doing it wrong for a long, long time.” —Elizabeth Gilbert, author of Big Magic and Eat Pray Love

No matter what you eat, how much you exercise, how skinny or young or wise you are, none of it matters if you’re not breathing properly.


There is nothing more essential to our health and well-being than breathing: take air in, let it out, repeat twenty-five thousand times a day. Yet, as a species, humans have lost the ability to breathe correctly, with grave consequences.

Journalist James Nestor travels the world to figure out what went wrong and how to fix it. The answers aren’t found in pulmonology labs, as we might expect, but in the muddy digs of ancient burial sites, secret Soviet facilities, New Jersey choir schools, and the smoggy streets of São Paulo. Nestor tracks down men and women exploring the hidden science behind ancient breathing practices like Pranayama, Sudarshan Kriya, and Tummo and teams up with pulmonary tinkerers to scientifically test long-held beliefs about how we breathe.

Modern research is showing us that making even slight adjustments to the way we inhale and exhale can jump-start athletic performance; rejuvenate internal organs; halt snoring, asthma, and autoimmune disease; and even straighten scoliotic spines. None of this should be possible, and yet it is.

Drawing on thousands of years of medical texts and recent cutting-edge studies in pulmonology, psychology, biochemistry, and human physiology, Breath turns the conventional wisdom of what we thought we knew about our most basic biological function on its head. You will never breathe the same again.

Excerpt

One

 

The Worst Breathers in the Animal Kingdom

 

The patient arrived, pale and torpid, at 9:32 a.m. Male, middle-aged, 175 pounds. Talkative and friendly but visibly anxious. Pain: none. Fatigue: a little. Level of anxiety: moderate. Fears about progression and future symptoms: high.

 

Patient reported that he was raised in a modern suburban environment, bottle-fed at six months, and weaned onto jarred commercial foods. The lack of chewing associated with this soft diet stunted bone development in his dental arches and sinus cavity, leading to chronic nasal congestion.

 

By age 15, patient was subsisting on even softer, highly processed foods consisting mostly of white bread, sweetened fruit juices, canned vegetables, Steak-umms, Velveeta sandwiches, microwave taquitos, Hostess Sno Balls, and Reggie! bars. His mouth had become so underdeveloped it could not accommodate 32 permanent teeth; incisors and canines grew in crooked, requiring extractions, braces, retainers, and headgear to straighten. Three years of orthodontics made his small mouth even smaller, so his tongue no longer properly fit between his teeth. When he stuck it out, which he did often, visible imprints laced its sides, a precursor to snoring.

 

At 17, four impacted wisdom teeth were removed, which further decreased the size of his mouth while increasing his chances of developing the chronic nocturnal choking known as sleep apnea. As he aged into his 20s and 30s, his breathing became more labored and dysfunctional and his airways became more obstructed. His face would continue a vertical growth pattern that led to sagging eyes, doughy cheeks, a sloping forehead, and a protruding nose.

 

This atrophied, underdeveloped mouth, throat, and skull, unfortunately, belongs to me.

 

I'm lying on the examination chair in the Stanford Department of Otolaryngology Head and Neck Surgery Center looking at myself, looking into myself. For the past several minutes, Dr. Jayakar Nayak, a nasal and sinus surgeon, has been gingerly coaxing an endoscope camera through my right nasal cavity. He's gone so deep into my head that it's come out the other side, into my throat.

 

"Say eeee," he says. Nayak has a halo of black hair, square glasses, cushioned running shoes, and a white coat. But I'm not looking at his clothes, or his face. I'm wearing a pair of video goggles that are streaming a live feed of the journey through the rolling dunes, swampy marshes, and stalactites inside my severely damaged sinuses. I'm trying not to cough or choke or gag as that endoscope squirms a little farther down.

 

"Say eeee," Nayak repeats. I say it and watch as the soft tissue around my larynx, pink and fleshy and coated in slime, opens and closes like a stop-motion Georgia O'Keeffe flower.

 

This isn't a pleasure cruise. Twenty-five sextillion molecules (that's 250 with 20 zeros after it) take this same voyage 18 times a minute, 25,000 times a day. I've come here to see, feel, and learn where all this air is supposed to enter our bodies. And I've come to say goodbye to my nose for the next ten days.

 

For the past century, the prevailing belief in Western medicine was that the nose was more or less an ancillary organ. We should breathe out of it if we can, the thinking went, but if not, no problem. That's what the mouth is for.

 

Many doctors, researchers, and scientists still support this position. Breathing tubes, mouthbreathing, and nasal breathing are all just means to the same end. There are 27 departments at the National Institute of Health devoted to lungs, eyes, skin disease, ears, and so on. The nose and sinuses aren't represented in any of them.

 

Nayak finds this absurd. He is the chief of rhinology research at Stanford. He heads an internationally renowned laboratory focused entirely on understanding the hidden power of the nose. He's found that those dunes, stalactites, and marshes inside the human head orchestrate a multitude of functions for the body. Vital functions. "Those structures are in there for a reason!" he told me earlier. Nayak has a special reverence for the nose, which he believes is greatly misunderstood and underappreciated. Which is why he's so interested to see what happens to a body that functions without one. Which is what brought me here.

 

Starting today, I'll spend the next quarter of a million breaths with silicone plugs blocking my nostrils and surgical tape over the plugs to stop even the faintest amount of air from entering or exiting my nose. I'll breathe only through my mouth, a heinous experiment that will be exhausting and miserable, but has a clear point.

 

Forty percent of today's population suffers from chronic nasal obstruction, and around half of us are habitual mouthbreathers, with females and children suffering the most. The causes are many: dry air to stress, inflammation to allergies, pollution to pharmaceuticals. But much of the blame, I'll soon learn, can be placed on the ever-shrinking real estate in the front of the human skull.

 

When mouths don't grow wide enough, the roof of the mouth tends to rise up instead of out, forming what's called a V-shape or high-arched palate. The upward growth impedes the development of the nasal cavity, shrinking it and disrupting the delicate structures in the nose. The reduced nasal space leads to obstruction and inhibits airflow. Overall, humans have the sad distinction of being the most plugged-up species on Earth.

 

I should know. Before probing my nasal cavities, Nayak took an X-ray of my head, which provided a deli-slicer view of every nook and cranny in my mouth, sinuses, and upper airways.

 

"You've got some . . . stuff," he said. Not only did I have a V-shape palate, I also had "severe" obstruction to the left nostril caused by a "severely" deviated septum. My sinuses were also riddled with a profusion of deformities called concha bullosa. "Super uncommon," said Nayak. It was a phrase nobody wants to hear from a doctor.

 

My airways were such a mess that Nayak was amazed I hadn't suffered from even more of the infections and respiration problems I'd known as a kid. But he was reasonably certain I could expect some degree of serious breathing problems in the future.

 

Over the next ten days of forced mouthbreathing, I'll be putting myself inside a kind of mucousy crystal ball, amplifying and hastening the deleterious effects on my breathing and my health, which will keep getting worse as I get older. I'll be lulling my body into a state it already knows, that half the population knows, only multiplying it many times.

 

"OK, hold steady," Nayak says. He grabs a steel needle with a wire brush at the end. It's the size of a mascara brush. I'm thinking, He's not going to put that thing up my nose. A few seconds later, he puts that up my nose.

 

I watch through the video goggles as Nayak maneuvers the brush deeper. He keeps sliding until the brush is no longer up my nose, no longer playing around my nose hair, but wiggling inside of my head a few inches deep. "Steady, steady," he says.

 

When the nasal cavity gets congested, airflow decreases and bacteria flourish. These bacteria replicate and can lead to infections and colds and more congestion. Congestion begets congestion, which gives us no other option but to habitually breathe from the mouth. Nobody knows how soon this damage occurs. Nobody knows how quickly bacteria accumulate in an obstructed nasal cavity. Nayak needs to grab a culture of my deep nasal tissue to find out.

 

I wince as I watch him twist the brush deeper still, then spin it, skimming off a layer of gunk. The nerves this far up the nose are designed to feel the subtle flow of air and slight modulations in air temperature, not steel brushes. Even though he's dabbed an anesthetic in there, I can still feel it. My brain has a hard time knowing exactly what to do, how to react. It's difficult to explain, but it feels like someone is needling a conjoined twin that exists somewhere outside of my own head.

 

"The things you never thought you'd be doing with your life," Nayak laughs, putting the bleeding tip of the brush into a test tube. He'll compare the 200,000 cells from my sinuses with another sample ten days from now to see how nasal obstruction affects bacterial growth. He shakes the test tube, hands it to his assistant, and politely asks me to take the video goggles off and make room for his next patient.

 

Patient #2 is leaning against the window and snapping photos with his phone. He's 49 years old, deeply tanned with white hair and Smurf-blue eyes, and he's wearing spotless beige jeans and leather loafers without socks. His name is Anders Olsson, and he's flown 5,000 miles from Stockholm, Sweden. Along with me, he's ponied up more than $5,000 to join the experiment.

 

I'd interviewed Olsson several months ago after coming across his website. It had all the red flags of flakiness: stock images of blond women striking hero poses on mountaintops, neon colors, frantic use of exclamation points, and bubble fonts. But Olsson wasn't some fringe character. He'd spent ten years collecting and conducting serious scientific research. He'd written dozens of posts and self-published a book explaining breathing from the subatomic level on up, all annotated with hundreds of studies. He'd also become one of Scandinavia's most respected and popular breathing therapists, helping to heal thousands of patients through the subtle power of healthy breathing.

 

When I mentioned during one of our Skype conversations that I would be mouthbreathing for ten days during an experiment, he cringed. When I asked if he wanted to join in, he refused. "I do not want to," he declared. "But I am curious."

 

Now, months later, Olsson plops his jet-lagged body into the examination chair, puts on the video glasses, and inhales one of his last nasal breaths for the next 240 hours. Beside him, Nayak twirls the stainless-steel endoscope the way a heavy metal drummer handles a drumstick. "OK, lean your head back," says Nayak. A twist of the wrist, a crane of the neck, and he goes deep.

 

The experiment is set up in two phases. Phase I consists of plugging our noses and attempting to live our everyday lives. We'll eat, exercise, and sleep as usual, only we'll do it while breathing only through our mouths. In Phase II, we'll eat, drink, exercise, and sleep like we did during Phase I, but we'll switch the pathway and breathe through our noses and practice a number of breathing techniques throughout the day.

 

Between phases we'll return to Stanford and repeat all the tests we've just taken: blood gases, inflammatory markers, hormone levels, smell, rhinometry, pulmonary function, and more. Nayak will compare data sets and see what, if anything, changed in our brains and bodies as we shifted our style of breathing.

 

I'd gotten a fair share of gasps from friends when I told them about the experiment. "Don't do it!" a few yoga devotees warned. But most people just shrugged. "I haven't breathed out of my nose in a decade," said a friend who had suffered allergies most of his life. Everyone else said the equivalent of: What's the big deal? Breathing is breathing.

 

Is it? Olsson and I will spend the next 20 days finding out.

 

. . .

 

A while back, some 4 billion years ago, our earliest ancestors appeared on some rocks. We were small then, a microscopic ball of sludge. And we were hungry. We needed energy to live and proliferate. So we found a way to eat air.

 

The atmosphere was mostly carbon dioxide then, not the best fuel, but it worked well enough. These early versions of us learned to take this gas in, break it down, and spit out what was left: oxygen. For the next billion years, the primordial goo kept doing this, eating more gas, making more sludge, and excreting more oxygen.

 

Then, around two and a half billion years ago, there was enough oxygen waste in the atmosphere that a scavenger ancestor emerged to make use of it. It learned to gulp in all that leftover oxygen and excrete carbon dioxide: the first cycle of aerobic life.

 

Oxygen, it turned out, produced 16 times more energy than carbon dioxide. Aerobic life forms used this boost to evolve, to leave the sludge-covered rocks behind and grow larger and more complex. They crawled up to land, dove deep into the sea, and flew into the air. They became plants, trees, birds, bees, and the earliest mammals.

 

Mammals grew noses to warm and purify the air, throats to guide air into lungs, and a network of sacs that would remove oxygen from the atmosphere and transfer it into the blood. The aerobic cells that once clung to swampy rocks so many eons ago now made up the tissues in mammalian bodies. These cells took oxygen from our blood and returned carbon dioxide, which traveled back through the veins, through the lungs, and into the atmosphere: the process of breathing.

 

The ability to breathe so efficiently in a wide variety of ways-consciously and unconsciously; fast, slow, and not at all-allowed our mammal ancestors to catch prey, escape predators, and adapt to different environments.

 

It was all going so well until about 1.5 million years ago, when the pathways through which we took in and exhaled air began to shift and fissure. It was a shift that, much later in history, would affect the breathing of every person on Earth.

 

I'd been feeling these cracks for much of my life, and chances are you have, too: stuffy noses, snoring, some degree of wheezing, asthma, allergies, and the rest. I'd always thought they were a normal part of being human. Nearly everyone I knew suffered from one problem or another.

 

But I came to learn that these problems didn't randomly develop. Something caused them. And the answers could be found in a common and homely human trait.

 

 

A few months before the Stanford experiment, I flew to Philadelphia to visit Dr. Marianna Evans, an orthodontist and dental researcher whoÕd spent the last several years looking into the mouths of human skulls, both ancient and modern. We were standing in the basement of the University of Pennsylvania Museum of Archaeology and Anthropology, surrounded by several hundred specimens. Each was engraved with letters and numbers and stamped with its ÒraceÓ: Bedouin, Copt, Arab of Egypt, Negro Born in Africa. There were Brazilian prostitutes, Arab slaves, and Persian prisoners. The most famous specimen, I was told, came from an Irish prisoner whoÕd been hanged in 1824 for killing and eating fellow convicts.

 

The skulls ranged from 200 to thousands of years old. They were part of the Morton Collection, named after a racist scientist named Samuel Morton, who, starting in the 1830s, collected skeletons in a failed attempt to prove the superiority of the Caucasian race. The only positive outcome of Morton's work is the skulls he spent two decades gathering, which now provide a snapshot of how people used to look and breathe.

Author

James Nestor is an author and journalist who has written for Scientific American, Outside, The New York Times, The Atlantic, and more. His latest book, Breath: The New Science of a Lost Art, was an instant New York Times and London Sunday Times bestseller and will be translated into more than 35 languages. Breath was awarded the Best General Nonfiction Book of 2020 by the American Society of Journalists and Authors and was a Finalist for Best Science Book of 2021 by the Royal Society. Nestor’s first book, Deep: Freediving, Renegade Science, and What the Ocean Tells Us About Ourselves, was a Finalist for the 2014 PEN/ESPN Award For Literary Sports Writing and an Amazon Best Science Book of 2014. Nestor has presented his work at Stanford Medical School, the United Nations, and on radio and television shows including Fresh Air with Terry Gross, ABC’s Nightline, CBS Morning News, and dozens of NPR programs. He lives and breathes in San Francisco. View titles by James Nestor