"Its color comes from white blood cells and other ... he adds. Like yellow mucus, "green mucus is a sign that your body is actively fighting off an infection," says Dr. Connor.

Phlegm might seem like an everyday nuisance, but it can serve as a critical indicator of your body’s respiratory and systemic ...

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 ...