A cloudy goo points to the beginning of a cold, allergies, or dehydration. "It happens when nose hair cells have been injured by inflammation, so the mucus slows down, loses moisture, and becomes white," says Stringer. Guzzle H2O and spritz your nostrils with saline spray (available at drugstores); it will help moisturize the nose and flush out any pesky particles.
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Yellow or green
Here's a case where you can't judge your mucus by its color. Contrary to popular belief, green mucus doesn't necessarily signify a bacterial infection and yellow a virus, says Stringer. "The color change depends on how much mucus is in your nose as well as how much inflammation is present." But both colors do indicate that you're sick and your immune system is trying to fight back. The tinge is from a large quantity of white blood cells that arrived on the scene to help battle the bug. When they die, they leave behind a green-colored enzyme that tinges your mucus.
Gold and super sticky
Mucus that's a darker shade of yellow with a peanut butter-like consistency could point to fungal sinusitis, a type of infection caused by mold spores that get trapped in the nose. "We breathe in mold all the time and most people will clear it right down their throat, but if you are allergic, it will stick, causing swelling in your nasal passages," explains Stringer. "The spores grow and you lose moisture in the nose, which is what causes the very unusual and persistent color and texture of the mucus." With this hue, you should see your doctor ASAP.
Red or pink
Specks of this hue are blood from broken blood vessels, which lie very close to the surface of the inside of the nose. When you blow too hard or the lining is too dry, they can rupture, says Stringer.
Super-dark mucus could mean you inhaled pollutants or smoke, but it may also signal a chronic sinus infection or fungus. "Fungus likes to hang out in dead tissue, and if your mucus has been backed up and accumulating, it's the perfect environment for fungus to latch on to and hang out," says Stringer. In any case, you should check in with your doctor.
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This article was originally published by our partners at Prevention.