Modern humans became the “worst breathers in the animal kingdom” as soft diets shrank our jaws and mouth breathing habits sparked sleep issues, stress, weak immunity, and chronic disease. Nestor weaves his wild experiments — like mouth-taping at Stanford and pulmonaut quests — with hard science on nasal pathways, plus ancient wisdom from Pranayama yogis, Tibetan Tummo monks, and shamanic breath rituals that tuned bodies for superhuman calm and endurance. Under the data pulses breath's quiet alchemy: your built-in gateway to nervous system coherence, deeper focus, and that subtle, embodied ease.

What you can get from reading it

• A clear understanding of why nasal breathing (vs. mouth breathing) changes your physiology, from sleep quality and snoring to immune function and jaw development.​
• Practical techniques like slow “resonant” breathing, light “less is more” breathing, alternate nostril breathing, and breath holds — with simple how‑to guidance you can actually try the same day.​
• A felt sense of how changing your CO₂ tolerance and exhale length can flip your nervous system from fight‑or‑flight into deep rest, focus, and emotional steadiness.​
• An appreciation for ancient practices like Pranayama, Tummo, and Sudarshan Kriya, reframed through modern research so you see them as nervous‑system technology, not just esoteric rituals.​​
• Concrete, slightly edgy stories from freedivers to Soviet labs to choir schools that make the science visceral and help you remember why to stick with the practices when they feel uncomfortable or strange.​
• A new relationship with your own breath as a daily, built‑in tool for self‑regulation, recovery, and subtle altered states, rather than something automatic and ignored.​

About the author

James Nestor is a science journalist who got obsessed with breathing after reporting on extreme free divers who trained themselves to dive hundreds of feet on a single breath and described profound states of calm and presence underwater. He’s written for outlets like Outside, Scientific American, and The Atlantic, and spent nearly a decade traveling to labs, ancient sites, and fringe “pulmonauts” to test claims on his own body, which gives the book a grounded, curious, “try it with me” feel instead of a top‑down guru voice.