If your mucus is gray or black... …you likely inhaled dark-colored particles, like smoke from a fire or heavy exhaust.

This cold and flu season, you may be looking for clues you're getting better anywhere you can find them, even in the color of ...

When a white blood cell finds a germ, it latches onto it. Then it changes its shape to surround the germ. You can imagine the ...

Carleton-Nathan says yellow, green, red, pink or brown mucus is not an immediate cause for alarm. Even dark yellow snot does not usually warrant a trip to the doctor. “In general, darker color ...

you’ve likely examined your mucus color, from yellow to green, for signs you may be healing. “We are in the midst of one of the most severe flu seasons in the past few decades, and it is ...