What Your Snot Says About You (Infographic)

Diagram of sinuses and chart of mucus colors.
Nasal discharge can be an indicator of health. (Image credit: By Karl Tate, Infographics Artist)

The paranasal sinuses are air-filled cavities that are lined with mucus-making cells. The mucus serves to keep the nose from drying out and to trap contaminants before they reach the lungs.


Mucus (”snot”) is made of water, proteins, antibodies and salts. Its color is an indicator of health:


CLEAR indicates healthy.


WHITE is thick mucus indicating sinus congestion.


YELLOW means that infection-fighting cells are battling a cold.


GREEN indicates that your immune system is fighting a bacterial infection.


RED is blood in the mucus, possibly from broken tissue in the nose.


BROWN could be blood or an inhaled contaminant.


BLACK, unless you're a smoker, could mean a fungal infection.



Karl Tate
LiveScience Infographic Artist
Karl has been Purch's infographics specialist across all editorial properties since 2010.  Before joining Purch, Karl spent 11 years at the New York headquarters of The Associated Press, creating news graphics for use around the world in newspapers and on the web.  He has a degree in graphic design from Louisiana State University.