Health Conditions A-Z Infectious Diseases Common Cold What Are Boogers? By Maggie O'Neill Maggie O'Neill Maggie O’Neill is a health writer and reporter based in New York who specializes in covering medical research and emerging wellness trends, with a focus on cancer and addiction. Prior to her time at Health, her work appeared in the Observer, Good Housekeeping, CNN, and Vice. She was a fellow of the Association of Health Care Journalists’ 2020 class on Women’s Health Journalism and 2021 class on Cancer Reporting. In her spare time, she likes meditating, watching TikToks, and playing fetch with her dog, Finnegan. health's editorial guidelines Updated on April 7, 2024 Medically reviewed by Kashif J. Piracha, MD Medically reviewed by Kashif J. Piracha, MD Kashif J. Piracha, MD, FACP, FASN, FNKF, is a practicing physician at Methodist Willowbrook Hospital. learn more Trending Videos Close this video player PeopleImages / Getty Images You probably heard a lot of jokes about boogers growing up and were taught not to pick them. You may have wondered what are boogers made of. Boogers are pieces of dried nasal mucus that trap air pollutants, bacteria, dirt, pollen, and other harmful substances. Your body often produces more mucus than usual if you have a bacterial or viral infection or allergies. Where does snot come from? Snot—unlike boogers, which are hard nasal mucus—is liquid nasal mucus that drips out of your nose or down your throat. There are several snot colors, such as black, green, white, or yellow. Your boogers may also sometimes be bloody. Read on to learn what boogers are, including what they are made of and why you have them (and why you shouldn't pick them). How To Soothe a Sore Throat Fast What Are Boogers Made Of? Boogers are pieces of dried nasal mucus trapped in your nose. Mucus is the slimy material that mucus membranes lining your nostrils create to trap air pollutants, bacteria, dirt, pollen, and other harmful substances. Your nose and sinuses make 1 liter (l) of snot per day. What Is Snot? Snot is liquid nasal mucus—whereas boogers are dried nasal mucus—that drips out of your nose if you have a runny nose. You may notice snot dripping down your throat if you have post-nasal drip. Your body usually makes more snot than usual if you have an infection to get rid of the bacteria or virus making you sick. What Do the Colors of Boogers Mean? The color of boogers reflects the airborne dirt, dust, and debris they block. Boogers nearly always have some color to them, including: Black or brown: Caused by smoking or certain types of lung disease Dark or bright green: Usually a sign of a bacterial infection Red: Can occur if your nasal tissue is dry and bleeds or be a sign of a bacterial infection White: May mean that you are congested Yellow: Signals an infection How Do Boogers Form Boogers form when air passes through your nostrils, drying up nasal mucus. Goblet cells secrete mucin (a fluid that lubricates the airways) and line the inside of the nostrils. This lubrication helps protect against: Air pollution Bacteria and viruses Dirt Dust Pollen Nasal mucus traps these substances in the hairs of your nose (cilia). The air that passes through nasal breathing dries up the snot, forming boogers. Why Do You Have Boogers? Nasal mucus that dries up and becomes boogers helps keep you healthy. Snot helps trap airborne dirt, dust, and debris you inhale through your nose, preventing it from reaching your lungs. Several things can cause enough boogers to form in your nostrils that you feel stuffed up, including allergies, a cold, and sinusitis. Having a stuffy nose does not mean you are necessarily sick. Dry air can also cause the sensation. Infections The mucus in your nostrils helps keep infectious microbes, like bacteria and viruses, from getting into your airway and making you sick. Producing boogers is normal and does not mean you are sick. An infection, such as a cold or sinusitis, can cause your body to produce more boogers. Bacterial or viral infections cause the mucus membranes that line your nose to become inflamed, leading to more snot. Allergies Allergens and irritants, such as dust, mold, pollen, or smoke, also increase mucus production. Allergic rhinitis (hay fever) is inflammation of the nose. Other symptoms include a runny nose, itching, sore throat, and sneezing. How To Get Rid of Boogers Try a saline rinse if you feel like you cannot breathe through your nose. Saline rinses help clear away any mucus and shrink down the nasal turbinates, or soft tissues on the outside of the nasal passage. You'll flush the rinse through each of your nostrils. You can buy saline rinse over the counter or make your own. Nasal decongestants can also remove excess nasal mucus and boogers if the saline rinse does not help. Do not take nasal decongestants for more than three days. These drugs can cause rhinitis medicamentosa (rebound congestion), or inflammation in the nose. Antihistamines can also help decrease nasal production if you have allergies. Talk to a healthcare provider if these home remedies do not work, or you have: A cough that brings up mucus or lasts longer than 10 days Foul-smelling nasal discharge Nasal discharge that occurs after a head injury or with a fever Snot that drips out of one nostril or is a color other than white or yellow A stuffy nose that occurs with blurry vision or swelling of the face or lasts longer than three weeks Throat pain White or yellow spots on the tonsils or throat Avoid Picking Your Nose You'll want to avoid picking your nose, medically known as rhinotillexomania. Picking your nose can damage the delicate tissue that lines the nasal passages. You might develop nosebleeds as a result. Putting a finger on or inside your nostril can also transmit any bacteria or viruses on that finger into your nose, increasing the risk of an infection. If you touch a surface like a doorknob, for example, that has cold viruses on it, you transfer viral particles into your body when you put that same unwashed finger in your nose to flick out a booger. It works the other way, too: Putting your fingers in your nose can transmit viruses and bacteria from your boogers to other surfaces you touch afterward, potentially making others sick. Use a tissue to blow your nose and wash your hands shortly after gently. Why Do I Have a Dry Cough at Night, and How Do I Stop It? A Quick Review Boogers, which are dried nasal mucus, may seem gross. Nasal mucus is pretty important, though: Snot helps trap airborne dirt, dust, and microbes that you breathe in and prevents them from reaching your lungs. Boogers can be yellow, green, or brown because of the particles that get trapped. Remember, do not pick your nose, which can introduce any germs on your finger into your body or transfer them to others. Was this page helpful? Thanks for your feedback! Tell us why! Other Submit 8 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Nemours KidsHealth. What's a booger? NIH News in Health. Marvels of mucus and phlegm. Dao DPD, Le PH. Histology, goblet cells. In: StatPearls. StatPearls Publishing; 2024. MedlinePlus. Allergic rhinitis. MedlinePlus. Stuffy or runny nose – adult. American Academy of Family Physicians. Decongestants: OTC relief for congestion. American Academy of Family Physicians. Nosebleeds. MedlinePlus. Common cold.