When phlegm has a yellow, green, or red color to it ... While there are plenty of reasons to quit smoking or vaping already, ...

Brown mucus could suggest possible infection, but also air pollution or excess smoking. Carleton-Nathan says yellow, green, red, pink or brown mucus is not an immediate cause for alarm.

People who have darkened mucus due to smoking should stop smoking. In addition to clearing up the mucus, quitting smoking provides many health benefits. Anyone exposed to pollutants on a regular ...