The nose warms and humidifies incoming air. We’ve heard that a lot.
However, when you dig into the scientific literature, you learn that nitric oxide (NO) might outweigh all other aspects of nasal breathing. It’s actually hard to overstate the benefits of nasal NO.
Which brings us to this week’s paper:
Nasal Nitric Oxide in Man
- Published in Thorax in 1999 (Read Full Summary Here)
This was a great overview of the many functions of nasal NO. Here are a few of my favorites. Check out the full summary for more.
The general consensus is that NO is continuously released in the paranasal sinuses. Because of this continuous release, a lower flow rate will result in higher concentrations. This could be yet another benefit of slow breathing: Increased nitric oxide delivery to the lungs.
Another amazing benefit of nasal NO is that it increases arterial oxygenation. For example, one study showed that nasal breathing increased tissue oxygenation 10% more than mouth breathing.
Finally, and this was my favorite part, a study showed that breathing humidified air through the mouth did not increase oxygenation; however, breathing supplemental NO through the mouth increased oxygenation similar to what is seen in nose breathing.
Although the warming and moistening effects are important, this suggests that nitric oxide might explain many of the benefits of nasal breathing.
I am continually amazed by everything nitric oxide does in the body. I think it’s my new favorite gas (never thought I’d have one of those!).
In good breath,
Nick
P.S. Who Needs Gas?.