Your nostrils take turns
In most people the two sides of the nose alternate congestion across a few hours. One side leads, then the other.
Established2 min read
Kayser described the nasal cycle in 1895. Erectile tissue in the turbinates swells under autonomic control, left and right out of phase. The period is often a few hours. Posture and illness ride on top of it.
The slower side conditions air differently, and some smell receptors work better in a low flow. The nose runs two experiments and refuses to run them at the same speed.
Caveats
- Not everyone has a clear cycle all the time. Illness can pin one side down.
Sources
- 1Hasegawa M., Kern E. B.. The Human Nasal Cycle. Mayo Clinic Proceedings 52, 1977.