Family Health What Is Mucus? Surprising Facts About Your Phlegm By Primary Care, January 25, 2018 You may call it mucus, phlegm, boogers, snot, or something extra cutesy. Whatever name you use for it, there’s much to learn about these little buggers. During cold or allergy season, for example, it can seem like mucus is clogging up your sinuses, nose, and throat and just trying to ruin your life. When you’re sneezing it out or coughing it up, mucus hardly seems like a good thing. However, mucus does have a purpose — and real benefits. Read on for useful facts about mucus to help you appreciate it. Have more questions about your health? Get them answered by contacting a UPMC primary care doctor. Gross But Good: What Is Mucus, Anyway? We tend to associate mucus with our noses, but it’s so much more. In fact, mucus is any viscous liquid your body produces to cover your organs and line any cavities. RELATED: Can Neti Pots Relieve Sinus Problems? A source of antiseptic enzymes, mucus shields your sinuses and: Protects your stomach lining against acid Keeps food moving down your esophagus Traps dust, bacteria, and other particles in the air before they get to your lungs Too Much of a Good Thing? Typically, your body can produce a liter of this sticky stuff each day. And when you’re sick, your body makes even more mucus or it becomes thicker. RELATED: What Makes My Nose Run? If the insides of your nose and sinuses are inflamed, it may take longer to get rid of extra mucus. So, when you’re sick and have more mucus and it’s draining slower, it may seem intolerable, but it’s actually important. What Does the Color of Mucus Mean? Normally, your mucus should be clear. Changes in the color of mucus sometimes can provide clues to your health. Here’s what the color of mucus indicates: Cloudy or white mucus is a sign of a cold. Yellow or green mucus is a sign of a bacterial infection. Brown or orange mucus is sign of dried red blood cells and inflammation (aka a dry nose). If you’re producing extra large amounts of mucus that make it difficult to breathe, or if you have concerns about the color of your mucus, contact your primary care doctor at UPMC.