5 Fun Facts About Boogers

Boogers may look gross, but they come from something that serves an important purpose: mucus. Boogers form when nasal mucus that has trapped dust, dirt and germs dries out. 

If you have children, you’ve probably heard some curious questions about boogers. Why do they come in different colors? Do they have germs? Is it OK to pick or eat them? 

Here are five fun facts about boogers that may surprise you:

Boogers start out as mucus, a sticky substance made mostly of water, along with proteins, salts and other substances. 

Your body makes mucus throughout the day to keep your nose, throat and other tissues moist. 

Most of the mucus in your nose travels down the back of your throat, where you swallow it without even noticing. But some stays behind and dries out, turning into boogers. 

The mucus that forms boogers plays an important role in protecting your body from germs. 

Mucus traps viruses, bacteria and other particles. Tiny hairlike structures called cilia help move the mucus and trapped particles along so they can be cleared away. 

“Mucus helps flush out substances like dirt, dust or bacteria before they can get into the lungs and cause irritation or breathing problems,” says Olga Rose, MD, a pediatrician at Scripps Clinic Rancho Bernardo. “It can also help keep you from inhaling viruses that can make you sick.” 

Boogers come in different colors, and there are several reasons why. 

Here’s what they may mean: 

Yellow or green: These colors often appear when your immune system responds to an infection. White blood cells and their enzymes can give mucus a yellow or green tint. 

Yellow or green mucus is common during a cold, but color alone cannot tell whether an infection is viral or bacterial or whether antibiotics are needed. 

Red or brownish: These colors may come from small amounts of blood caused by dry nasal tissues, irritation or frequent nose picking. Brown mucus can also contain old blood or inhaled dust. 

A small amount of blood usually isn’t serious, but contact your child's pediatrician if bleeding is frequent, heavy or difficult to stop. 

Black: Dark boogers can form when mucus traps soot, smoke or dirt. If black mucus persists without an obvious cause, contact your child’s pediatrician. In rare cases, black mucus can be a sign of a more serious health problem. 

Ever wonder why parents tell kids to stop picking their noses? It's not just because it's gross. 

Boogers can contain bacteria and viruses that spread to your fingers and anything you touch. Germs on your hands can also enter your nose when you pick it. 

Frequent nose picking can also irritate delicate nasal tissues and cause bleeding. 

So, what's a better way to get rid of boogers? 

Gently blow your nose into a tissue. If mucus is thick or dried out, saline nasal drops or spray can help loosen it. For babies and younger children who can't blow their noses, a bulb syringe or nasal aspirator may help. 

And don’t forget to wash your hands afterward.

Some kids like to eat their boogers. It may seem gross, but is it actually harmful? 

Occasionally eating a booger is unlikely to make you sick. After all, your body already swallows nasal mucus throughout the day. 

“Eating boogers is something we try to discourage,” says Dr. Rose. “It’s probably not harmful, but your body is getting rid of them for a reason, so it’s best to let nature take its course.” 

Still, it’s not a habit worth encouraging. Remind your child to use a tissue instead. 

Most boogers are harmless, but certain symptoms may mean it’s time to contact your child's pediatrician. 

Call your pediatrician if your child has: 

• Persistent nasal congestion or discharge lasting more than 10 days without improvement. 
• Symptoms that improve but then get worse. 
• Frequent nosebleeds or persistent bloody mucus. 
• Nasal discharge accompanied by persistent fever or significant facial pain. 

Seek immediate medical care if your child has trouble breathing. Call 911 for severe breathing difficulty. If your baby is younger than 3 months and has a fever of 100.4 degrees or higher, seek immediate medical evaluation. 

Remember, booger color alone usually isn’t enough to tell whether your child has an infection. How your child feels and whether other symptoms are present matter more.