Mucus isn't exactly something people give much thought to — until they're sick and dealing with a constantly runny nose. But mucus is actually an important part of a healthy immune system, according ...

When you're sick you'll often produce more phlegm, and might notice it's thicker or a different color: white, green, yellow or maybe even brown. Subscribe to our newsletter for the latest sci-tech ...

Add Yahoo as a preferred source to see more of our stories on Google. Americans are weathering the worst flu season in years, as a number of other respiratory illnesses circulate too, such as COVID-19 ...

I’m guessing you haven’t spent much time thinking about mucus recently. Sure, some of you with allergies or colds probably have, but not in a sort of optimistic way. Well, good news, there are ...

When a person has black or dark-colored mucus, they may have inhaled potentially harmful pollutants. Coughing up black mucus may also be due to an underlying infection or condition. Mucus serves an ...

Why Is My Mucus Yellow? Yellow mucus is a common symptom that occurs when your body is fighting a cold, sinus infection, or other respiratory issue. Its yellow color appears as white blood cells move ...

Add Yahoo as a preferred source to see more of our stories on Google. The color of your mucus can reveal some surprising things about your health. (Photo: Getty Images) (Getty Images/iStockphoto) ...