You breathe between 22,000 and 25,000 times a day. Every one of those breaths taken through the mouth skips a filter your body built for the job.
We teach this first, because every other exercise in the course rests on it.
Nitric oxide — the nose's biggest advantage
Breathing through the nose generates nitric oxide in the sinuses. The gas dilates blood vessels and improves blood flow through the lungs.
In 1998 three scientists won a Nobel Prize for establishing nitric oxide as a signalling molecule in the vascular system. Breathe through the mouth and none of it is produced.
The nose does more than admit air
The nose performs around thirty functions. Warming the air, humidifying it and filtering out dust and bacteria are only the first few.
Through the mouth, air arrives in the lungs cold, dry and unfiltered. It is why mouth breathers get ill more often.
It matters most at night
Sleeping with the mouth open lets the tongue fall backwards and narrows the airway. That produces snoring, and in serious cases breathing stops altogether — sleep apnoea.
Waking with a dry mouth is the tell that you spent the night breathing through it. It is usually the reason eight hours of sleep still leaves you tired.
What if your nose is blocked?
Most people assume they breathe through the mouth because the nose is blocked. It generally runs the other way: the nose is blocked because they breathe through the mouth.
Breath-hold exercises briefly raise carbon dioxide and nitric oxide, and the nose opens. Most people feel the difference in the first lesson.
