Human body · 34 s
Why your nose runs in the cold
Your nose runs in the cold on purpose.
Why. Your lungs want warm, damp air. Cold air is usually dry, so your nose works overtime to add moisture to every breath.
How. Nerves tell glands in the lining to pump out extra fluid. It’s thin and watery, nothing like what you get with a cold.
The twist. Warm breath condenses at your chilly nose tip too. A scarf over your nose helps.
How sure? “On purpose” means a protective reflex, while the condensation is plain physics. Not medical advice.
Sources
- Why does cold weather cause runny noses? (2009), NPR
- Why does my nose run when it’s cold? Smithsonian
What the video says
Your nose runs in the cold on purpose, mostly.
Your lungs want warm, damp air. Cold air is usually dry, so your nose works overtime to add moisture to every breath.
Nerves tell glands in the lining to pump out extra fluid. It's thin and watery, nothing like what you get with a cold.
Your breath adds to it. It's warm and humid, and at your chilly nose tip it condenses into droplets.
A scarf over your nose actually helps. Your sleeve says thanks.