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Breath: The New Science of a Lost Art

#booknotes #health #wellness #breathing

Most people probably don't give too much thought to their breath. Seems like an automatic thing that happens in order to sustain our life. Just as our heart beats without conscious effort, our breath continues. My mom mentioned this book to me as we took a stroll through Bramber Woods Park on a sunny, summer afternoon in 2021. She told me about a part of the book that said that the breath should be taken through the nose. I remember thinking...this sounds like a load of bull. Even though I practice yoga, especially meditation and pranayama. And even though I practice Wim Hof's breathing techniques AND even though I read all 3 of his books. Reading Breath: The New Science of a Lost Art by James Nestor really deepened my understanding of breathing and its importance on health.

This book uncovers that many modern aliments can be reduced or reversed simply by changing the way we breathe. Breathing in different ways can influence everything from your body weight to your overall health. Breath affects the size and function of your lungs. We can use breathing to hack into our nervous system and control our immune response and restore health. Changing how we breathe will help us live longer. No matter what you eat or how much you exercise or how skinny or wise you are...none of it will matter unless you are breathing correctly. The missing pillar of health is breath.

Mouth Breathing Destroys Your Health

How Breathing Came to Be

Evolution Doesn't Always Mean Progress

How the Body Makes Energy From Air and Food

Pituitary Gland and Vasopressin

Nostril Patterns

Left and Right Nostrils: HVAC System

Alternate Nostril Breathing - Nadi Shodhana

Nostril Breathing Is Mentioned in Ancient Texts

George Catlin - Nasal Breathing Habits of Indigenous Tribes

Tape Your Lips Shut When You Sleep

5 Tibetan Rites

The Full Circuit of Blood and the Thoracic Pump

Carbon Dioxide

The Journey of an Oxygen Molecule (Cruise Ship Example)

Breathe Less = More Carbon Dioxide and Increased Oxygen

Carbon Dioxide and Weight Loss

Slow Breathing and Prayer

Breathing Less and Blood pH

Slow Resting Heart Rate

Farming and Cooking Messed Us Up

Weston A. Price Says We Lackin' Vitamins

....But We Lackin' Chewing

Mouth Expanders

Chewing and Stem Cells

Autonomic Nervous System


Wim Hof

Vagus Nerve

Holotropic Breath Work

Amygdalae and Chemoreception

Carbon Dioxide Therapies

Some Unanswered Questions



Sudarshan Kriya

Breathing Can't Do Everything

Disease of Civilization


Mouth Breathing Destroys Your Health

The author, James Nestor, conducted a 20-day study at Stanford University to determine if the pathway through which we breathe—nose or mouth—matters? James Nestor and Anders Olsson plugged their nose, forcing them to breathe through their mouth for 10 days then carefully documented the state of their health. Dr. Jayakar Nayak, a nasal and sinus surgeon and Associate Professor at Stanford was overseeing the experiment.

Nestor's personal observations after 10 days of self-inflicted nasal obstructed:

  • His blood pressure spiked by 13 points, which put him into stage 1 hypertension. This state of chronically raised blood pressure, can cause heart attacks, stroke, and other serious problems.

  • Heart rate variability (a measure of nervous system balance) plummeted. Suggesting that his body was in a state of stress.

  • Pulse increased

  • Body temperature decreased

  • Mental clarity hit rock bottom

  • Felt: terrible

Olsson’s data mirrored Nestor's.

Official results from Dr. Jayakar Nayak’s lab ➜ After just 10 days of forced mouth breathing:

  • Catecholamine and stress-related hormones spiked which is an indication that their bodies were under physical and mental stress.

  • A bacteria infested Nestor's nose. If he continued mouth breathing this could have caused a sinus infection.

  • Blood pressure skyrocketed.

  • Heart rate variability plummeted.

  • Persistent nocturnal suffocation. (Snoring)

  • Experienced sleep apnea

  • They would likely end up with chronic snoring and obstructive sleep apnea... as well as hypertension, and metabolic / cognitive issues as a result

  • Fatigue, irritation, testiness, anxiety.

  • Bad breath

  • Frequently trips to the restroom

Not all of the measurements changed.

  • Blood sugar levels weren’t affected.

  • Cell counts in the blood remained the same

  • Ionized calcium remained the same,

  • as did most other blood markers.

Key message: Mouth breathing is terrible.

How Breathing Came to Be

One of the things this book discusses is how oxygen and carbon dioxide are crucial to our heath and evolution as a species. This "ball of sludge" example really helps solidify concepts later on.

Ball of sludge

Our earliest ancestors appeared on some rocks 4 billion years ago...we were a microscopic ball of sludge. We needed energy to sustain ourselves so we found a way to eat air.

Using carbon dioxide

Back then, the atmosphere was mostly carbon dioxide. We took this gas in, broke it down, and expelled what was left: oxygen.

Oxygen built we used that

We did this for a billion years and eventually oxygen built up in the atmosphere.

About 2.5 billion years ago, a scavenger ancestor emerged and it learned to take in all that leftover oxygen and excrete carbon dioxide. This was the first cycle of aerobic life.

More we evolved

Oxygen produced 16 times more energy than carbon dioxide. Aerobic life forms used this boost to evolve and grow larger / more complex. They took over the land, sea, and 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.

Full circle but evolved:

The aerobic cells that were once clinging to swampy rocks billions of years ago now made up the tissues in mammalian bodies. These cells took oxygen from our blood and returned carbon dioxide. The carbon dioxide flowed back through our veins, through our lungs, and into the atmosphere....this is the process of breathing.

Efficient breathing allowed us to thrive:

Our ability to breathe efficiently and in a variety of ways allowed our mammal ancestors to capture food, escape predators, and adapt to different environments.

Change. But for better or worse?

Things were going well until about 1.5 million years ago, when our airways began to shift and fissure. This shift now affect every person on Earth.

Stuffy noses, snoring, some degree of wheezing, asthma, allergies... these are the impact of these shift and fissures. You might think these are a normal part of being human. These problems didn’t randomly develop. Something caused them.

Evolution Doesn't Always Mean Progress

Nestor flew to Philly to examine a collection of skulls known as the Morton Collection. The skulls ranged from 200 to thousands of years old. Dr. Marianna Evans, an orthodontist and

dental researcher spent many years studying these human skulls.

All modern skulls showed some degree of crooked teeth. There are 5,400 different species of mammals on the planet and humans are now the only ones to routinely have misaligned jaws, overbites, underbites, and crooked teeth.

Why are we evolving in ways that make us sick?!

Evolution doesn’t always mean progress. It means change. And life can change for better or worse.

These days, the human body is changing in ways that have nothing to do with the “survival of the fittest.” We are adopting and passing down traits that are detrimental to our health. This concept is called dysevolution.

We are experiencing shrinking space in the front of the human skull. When mouths don’t grow wide enough, the roof of the mouth tends to rise upwards instead of out. The upward growth interferes with the development of the nasal cavity. It shrinks and disrupts the delicate structures in the nose. The reduced nasal space leads to obstruction and reduces airflow.

The next question is why is the available space in the front of the human skull shrinking?

How the Body Makes Energy From Air and Food

There are two ways: With oxygen: aerobic respiration

Without oxygen: anaerobic respiration

Anaerobic energy is generated only with glucose. It is quicker and easier for our body to access. When the body doesn't have enough oxygen....It kind of acts like a back up system or a turbo boost. When you need it can tap into it. Anaerobic energy is inefficient and can be toxic because it creates an excess of lactic acid. This is why aerobic respiration is so important. Remember those cells that evolve to eat oxygen 2.5 billion years ago... We've got 37 trillion of them in our bodies. When you run your body aerobically with oxygen you gained 16 times more energy efficiency over anaerobic. The key to exercise and the rest of life is to stay in that energy efficient aerobic zone for the majority of time.

The book offers a quick way to find your max heart rate for exercise:

Subtract your age from 180. I am 33. So my max heart rate (according to this) is

180-33= 147

This is the highest you can go to remain in the aerobic state. Longer exercise and training sessions can happen below that number. If you push it further, then the body will risk going too far into the anaerobic zone for too long. Instead of feeling good after a workout, you’ll feel a bit off (tired, shaky, nauseated). Note: There are different ways to calculate your max heart rate and aerobic zone. The 180 formula is a good guideline.

Pituitary Gland and Vasopressin

Mouth breathing breathing causes the body to lose 40% more water. You likely notice this at night. You would think that this moisture loss decreases the need to urinate at night. In your deepest stage of sleep, the pituitary gland secretes hormones, one of which is vasopressin. Vasopressin is an antidiuretic. It communicates with cells to store more water.

If your body spends inadequate time in deep sleep, which is what happens with chronic sleep apnea, vasopressin won't be secreted normally. The kidneys will release water which triggers the need to urinate. This also signals the brain that we need to rehydrate. We get thirsty and we have to pee more.

Chronic insomnia with long thought to be a psychological problem. But is often a breathing problem. They can't sleep because they can't breathe.

Nostril Patterns

1300 years ago, the Shiva Swarodaya (ancient Tantric text), described how nostrils open and close throughout the day. This book doesn't go into deep detail about this yoga but I am glad that James Nestor even mentioned it. For example, this book mentions that the cycle is influenced by the sun and the moon but this is just one of many variables that effect the nostril cycle. The main reason I am including Shiva Swarodaya in these book notes is to bring it to awareness. It is an ancient science called Swara Yoga.

Scientists have known for more than a century that the nostrils move to their own rhythm. They really do open and close like flowers throughout the day and night. This is called nasal cycles. A German physician named Richard Kayser described it in 1895. He noticed that the tissue lining one nostril of his patients seemed to quickly congest and close while the other would mysteriously open. After about 30 minutes to 4 hours, the nostrils switched.

Kayser attributed the shift to changes in sexual urges. The inside of the nose is covered in erectile tissue. It can saturate with blood and increase in size and stiffness in accordance with state of arousals.

After Kayser’s theory, many decades passed before anyone could offer a logical explanation for why the nostrils cycled or why it was lined with erectile tissue. There were many theories...what researchers eventually confirmed was that nasal erectile tissue mirrored states of health. It became inflamed during sickness or other states of imbalance. If the nose became infected, the nasal cycle became more pronounced and switched back and forth quickly.

Left and Right Nostrils: HVAC System

The right and left nasal cavities work like an HVAC system, controlling temperature and blood pressure and feeding the brain chemicals to alter our moods, emotions, and sleep states.

Right Nostril

The right nostril is a gas pedal When you’re inhaling primarily through the right channel:

  • Circulation speeds up

  • Body gets hotter

  • Cortisol level increases

  • Blood pressure increases

  • Heart rate increases

This happens because breathing through the right side of the nose activates the sympathetic nervous system, the “fight or flight” mechanism that puts the body in a more elevated state of alertness and readiness.

Breathing through the right nostril will also feed more blood to the opposite hemisphere of the brain, specifically to the prefrontal cortex, which has been associated with logical decisions, language, and computing.

Left Nostril

Inhaling through the left nostril has the opposite effect: it works as a kind of brake system.

The left nostril is more connected to the parasympathetic nervous system, the rest-and-relax side.

  • Lowers temperature

  • Blood pressure decrease

  • Cools the body

  • Reduces anxiety

Left-nostril breathing shifts blood flow to the opposite side of the prefrontal cortex, the right area that plays a role in creative thought, emotions, formation of mental abstractions, and negative emotions.

Alternate Nostril Breathing - Nadi Shodhana

There is a yoga(pranayama) practice dedicated to manipulating the body’s functions with forced breathing through the nostrils, called nadi shodhana. In Sanskrit, nadi means channel and shodhana means purification. The practice is also called alternate nostril breathing. This is something that I practice almost every day. I first learned it from Yoga With Adriene.

There are dozens of alternate nostril breathing techniques. I do the most basic one:

This really brings me into a different state. I usually do this in the evening when I am already really knocks me out! Sometimes I do it first thing in the morning and it brings me calm and stillness.

Nostril Breathing Is Mentioned in Ancient Texts

Breathing through your nose isn't a new concept. The book gives 3 examples but there are many more:

  1. The Ebers Papyrus, one of the oldest medical texts ever discovered dating back to approx. 1550BC, stated that the nostrils were supposed to feed air to the heart and lungs.... not the mouth.

  2. Genesis 2:7 stated “the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.”

  3. A Chinese Taoist text from 8th century AD stated that the nose was the “heavenly door.” It advises that breath must be taken in through it. It warns against breathing through the mouth “for breath would be in danger and illness would set in.”

George Catlin - Nasal Breathing Habits of Indigenous Tribes

Western societies didn't even consider the benefits of nasal breathing until the 1800s. It was likely due to an artist/researcher named George Catlin. In the 1830, Catlin's health was failing. He packed up his shit and headed deep into nature. He spent 6 years wandering the Great Plains. He wanted to document the lives of 50 Native American tribes. He lived with the Lakota Sioux, Pawnee, Crow, Osage, Omaha, Cheyenne, Mandan and Blackfeet.

He observed that they all had outstanding physical structure. He also noted that these people have never seen a dentist but their teeth were perfectly straight...and no one seemed to be sick of have health problems.

The tribes attributed their health to breathing. The Natives explained that breath inhaled through the mouth drained the body of strength, deformed the face, and caused stress and disease. On the other hand, breath inhaled through the nose kept the body strong, made the face beautiful, and prevented disease.

Healthy nasal breathing started habits at birth. Mothers in the tribes carefully close the baby’s lips with their fingers after each feeding. They continued to trained children to breathe through their noses and they carried this throughout their entire life.

George Catlin published a book in 1862 called The Breath of Life.

Tape Your Lips Shut When You Sleep

This might seems like a weird thing...but I tried it after reading this book and I do think there is value to it. Basically, you take a piece of surgical tape and put it over your lips when you sleep.

Dr. Mark Burhenne studied the links between mouth breathing and sleep for decades. He says that mouth breathing contributed to gum disease and bad breath. He says mouth breathing is the number one cause of cavities and that it is even more damaging than sugar consumption, bad diet, or poor hygiene. That's nuts.

The sinuses release nitric oxide. Nitric oxide is key in increasing circulation and delivering oxygen to the cells. Immune function, weight and circulation are greatly influenced by the amount of nitric oxide in the body. Nasal breathing alone can boost nitric oxide sixfold, which allows us to absorb about 18 percent more oxygen than breathing through the mouth.

Ann Kearney, a doctor in speech pathology at Stanford University uses mouth taping to help her patients. Its a use it or lose it situation. Like other parts of the body, the nasal cavity responds to whatever input it receives. When the nose isn't used will atrophy. Keeping the nose in constant use trains the sinuses inside the nasal cavity and throat to flex and stay open. Advice: So breathe through your nose when you're awake an conscious of it.

Tape your mouth shut to help you maintain your practice when you sleep.

I am going try this more consistently, for 30 days perhaps, and report back.

5 Tibetan Rites

The 5 Tibetan Rites a series of stretches that were passed down from one Buddhist monk to another for 2,500 years. Even if you breathe through your nose all day, you wont get the full benefit unless you have the lung capacity to hold in all that air. A few minutes of bending and breathing can increase your lung capacity. With that extra capacity, you can expand your life.

The stretches, called the Five Tibetan Rites, was brought to the Western world by writer Peter Kelder. Kelder heard about these techniques from a man that learned them from monasteries in the Himalayan mountains. Kelder described these techniques in a book titled The Eye of Revelation, published in 1939. Its honestly a quick routine. Here is a great demonstration:

Here is a really good explanation:

The Full Circuit of Blood and the Thoracic Pump

The blood flowing through our arteries and veins does a full circuit once a minute.

It pumps an average of 2,000 gallons of blood a day. This blood flow is essential to delivering fresh oxygenated blood to cells and removing waste.

The speed and strength of our circulation is influenced by the thoracic pump. Thoracic pump is the term for the pressure that builds inside the chest when we breathe.

When you inhale ➜ negative pressure draws blood into the heart.

When you exhale ➜ blood shoots back out into the body and lungs...back into circulation.

The thoracic pump is powered by the diaphragm which is the the muscle that sits beneath the lungs. The diaphragm lifts when you exhale, which shrinks the lungs. The diaphragm drops when you inhale, which expands the lungs.

These days, people only engage 10 percent of the range of the diaphragm when breathing, which overburdens the heart, elevates blood pressure, and causes a rash of circulatory problems.

Extending your breaths 50 to 70 percent of the diaphragm’s capacity will ease cardiovascular stress and allow your body to work more efficiently. The diaphragm is kind of like the second heart. It affects the rate and strength of the heartbeat.

Carbon Dioxide

James Nestor talks about one of his colleagues name Anders Olsson who stresses importance of carbon dioxide. Olsson stated that we have 100 times more carbon dioxide in our bodies than oxygen and that most of us need even more of it. In the "ball of sludge" example from earlier in these notes, Olsson stated that it wasn’t just oxygen but huge quantities of carbon dioxide that facilitated the explosion of life during the Cambrian Explosion 500 million years ago. Olsson believes that we can increase CO2 in our bodies to sharpen our minds, burn fat, and heal disease.

Olsson says that carbon dioxide could be beneficial He hypothesized that too much oxygen in the body could actually hurt you. Big heavy breaths might be the worst advice anyone could give you. This sort of breathing depletes our bodies of carbon dioxide.

The best way to improve many chronic health problems and to improve athletic performance and extend longevity was to focus on how we breathe specifically to balance oxygen and carbon dioxide in the body. To do this we need to learn how to inhale and exhale slowly.

Also, in 1940, Yandell Henderson, a physiologist at Yale, whos main focus was studying respiration and circulation stated:

"Carbon dioxide is the chief hormone of the entire body. It is the only one that is produced by every tissue. And that probably acts on every organ."

Though his experimentation he discovered that while breathing at a normal rate our lungs will absorb only 1/4 of the available oxygen in the air. The majority of that oxygen is exhaled back out. By taking longer breaths we allow our lungs to soak up more with less.

How could inhaling smaller amounts of air and having more carbon dioxide in our bloodstream increase oxygen in our tissues and organs? Let's go on a cruise.

The Journey of an Oxygen Molecule (Cruise Ship Example)

I really enjoyed this analogy of a cruise ship:

The nose and mouth are the gateways for the long journey of breath. If you follow the air ...its a pretty interesting journey it takes. The body is a collection of tubes. There are wide tubes, like the throat and sinuses and very narrow tubes like capillaries. The tubes that make up your lung tissues are very small. There a shit ton of them. 1500 miles. That's from Toronto to Cuba.

Each breath travels down the throat and eventually splits into the right and left lungs. As it keeps going, that breath gets pushed into smaller tubes called the bronchioles until it dead-ends at 500 million little structures called the alveoli.

The author uses a good analogy to explain the rest of the journey. Imagine yourself about to take a cruise. You have to wait in the waiting area at the dock when a ship approaches. You go through security, board the ship, and sail off.

This is similar to the path oxygen molecules take once they reach the alveoli.

The alveoli is like the dock and it is surrounded by a river of plasma filled with red blood cells which are the boats.

As each boat (cell) passes by, passengers (oxygen molecules) squeeze through the membranes of the alveoli and lodge themselves inside one. The passengers have boarded.

The cellular cruise ship has a bunch of guest rooms. These guestrooms are protein called hemoglobin. Oxygen finds a seat inside a hemoglobin and then the red blood cell sails upstream, deeper into the body.

As blood passes through tissues and muscles, oxygen will disembark, providing fuel to hungry cells. As oxygen gets off the cell, other passengers board the cell...mainly carbon dioxide which is the “waste product” of metabolism. The cruise ship will begin a return journey back to the lungs.

The cruise ship eventually ends up and back at the port (lungs). Carbon dioxide exit the body through the alveoli, up the throat, and out the mouth and nose in an exhale.

Every breath you take....this is what happens. This is how every healthy cell gets it oxygen.

This blows my damn mind. What's even more intriguing are the numbers...the scale to which this is happening: The whole cruise takes approximately one minute. We have 25 trillion red blood cells(boats).

There are 270 million hemoglobin(guestrooms).

Each guest room seats 4 oxygen molecules(passengers).

That is ONE BILLION molecules of oxygen boarding and disembarking within each red blood cell.

Breathe Less = More Carbon Dioxide and Increased Oxygen

So back to this question:

How could inhaling smaller amounts of air and having more carbon dioxide in our bloodstream increase oxygen in our tissues and organs?

That cruise ship example we understand HOW the processes works.