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By James NestorRating: 4.8/5Released: 2020

Breath

"The New Science of a Lost Art"

ARC Integration Hook:

Guides ARC's breathing protocol recommendations during stress checks and morning lung oxygenation timers.

In *Breath*, science journalist James Nestor investigates a basic but neglected aspect of human health: how we breathe. Nestor travels the world to explore the evolutionary, physiological, and neurological differences between mouth breathing and nasal breathing, showing that how we inhale and exhale dictates our sleep quality, metabolic speed, and stress levels.

Mouth Breathing vs. Nasal Breathing

Nestor explains that humans have become chronic mouth breathers due to changes in jaw structure caused by modern soft diets. This shift has severe biological consequences:

Mouth Breathing: Bypasses the body's natural air filtration and humidification systems. It triggers the sympathetic nervous system ("fight or flight"), raising heart rate, increasing blood pressure, and contributing to sleep apnea, snoring, and daytime fatigue.
Nasal Breathing: Releases nitric oxide, a molecule that plays a vital role in increasing oxygen circulation, dilating blood vessels, and activating the parasympathetic nervous system ("rest and digest").

Sleep Apnea and Circadian Sleep Structure

Mouth breathing during sleep causes the soft tissues in the back of the mouth to collapse, obstructing the airway. This results in sleep apnea and snoring, which fragment sleep architecture by forcing the brain to wake up briefly to gasp for air, preventing you from reaching slow-wave deep sleep.

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Tip

> Nestor details "mouth taping"—using a small strip of surgical tape to keep lips closed during sleep—as a simple, effective method to force nasal breathing, eliminate snoring, and deepen sleep.

Respiratory Protocols

Nestor outlines key exercises to restore optimal breathing:

1. Slower Breathing: Breathe in for 5.5 seconds, and out for 5.5 seconds (about 5.5 breaths per minute). This matches the natural resonance rhythm of human blood circulation.
2. Hypoventilation: Practice breathing less to build carbon dioxide tolerance, which enhances oxygen delivery to cells via the Bohr effect.

How ARC Applies This

ARC incorporates Nestor's research into daily check-ins and recovery guides. The app prompts you to practice Nasal Oxygenation during morning light windows and offers structured 5.5-second breathing guides during high-stress alert periods to help you reset your nervous system.

Reviewed ByARC Scientific Team
Author BiographyScience Journalist & Author

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