An interesting topic explored in Breath: The New Science of a Lost Art by James Nestor relates to the science behind Nadi Shodhana Pranayama, or alternate nostril breathing. Premium members have previously been granted access to a short breath-work exercise led by Veronica Cruz (my mom) here.
“The right nostril is a gas pedal. When you’re inhaling primarily through this channel, circulation speeds up, your body gets hotter, and cortisol levels, blood pressure, and heart rate all increase. 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.
Inhaling through the left nostril has the opposite effect: it works as a kind of brake system to the right nostril’s accelerator. The left nostril is more deeply connected to the parasympathetic nervous system, the rest-and-relax side that lowers temperature and blood pressure, cools the body, and 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.”
-James Nestor, Breath: The New Science of a Lost Art
“There are dozens of alternate nostril breathing techniques. I’ve started with the most basic. It involves placing an index finger over the left nostril and then inhaling and exhaling only through the right. I did this two dozen times after each meal today, to heat up my body and aid my digestion. Before meals, and any other time I wanted to relax, I’d switch sides, repeating the same exercise with my left nostril open. To gain focus and balance the body and mind, I followed a technique called surya bheda pranayama, which involves taking one breath into the right nostril, then exhaling through the left for several rounds.”
-James Nestor, Breath: The New Science of a Lost Art
“There’s a yoga practice dedicated to manipulating the body’s functions with forced breathing through the nostrils. It’s called nadi shodhana pranayama —in Sanskrit, nadi means “channel” and shodhana means “purification”—or, more commonly, alternate nostril breathing.”
-James Nestor, Breath: The New Science of a Lost Art
The book discusses the difference between breathing through each nostril which can be summarized below:
- Breathing through the right nostril:
- Activates the left side of the brain, which is associated with the prefrontal cortex, decision making, language, and computing
- Activates the sympathetic “fight or flight” nervous system, increasing alertness
- Breathing through the left nostril:
- Activates the right side of the brain, which is associated with processing emotions and creativity.
- Activates the parasympathetic “rest and digest” nervous system
- Lowers temperature and blood pressure
