The buildup of excess mucus in your nasal passages and throat is a common and uncomfortable symptom of many illnesses.

Being sick with a cold or other congestion-causing illness comes with a variety of symptoms, but a particularly annoying one is the buildup of mucus in your nasal passages and throat.

In addition to causing general discomfort, all the excess phlegm can make it difficult to talk and make you feel like you constantly need to swallow or spit. On the latter front, is one of those throat-clearing mechanisms better than the other?

Below, medical experts break it down.

First of all, what exactly is mucus?

“Mucus is a slippery, gel-like substance produced by mucous membranes in the body ― especially in the respiratory, digestive and urogenital tracts,” Dr. Heather Viola, an internal medicine doctor with the Mount Sinai Health System, told HuffPost. “It’s mostly water, but also contains proteins like mucins, antibodies, enzymes and salts.

These antibodies and enzymes in particular can fight infection ― just one of the many purposes of mucus.

“Mucus works to moisturize and protect tissues, trap dust and allergens and aid immune defense by flushing out irritants,” Viola noted. “Phlegm is a type of mucus specifically coming from lungs and lower airways, particularly when you are sick. It tends to be thicker and stickier than normal mucus and traps and expels pathogens.”

As with rectangles and squares, all phlegm is mucus, but not all mucus is phlegm. Viola added that phlegm is a more accurate term when referring to throat or chest congestion.

Why does it build up in your throat when you’re sick?

“When you’re sick with a cold, flu or sinus infection, your body ramps up mucus production to trap and flush out pathogens, keep inflamed tissues moist and support immune responses,” said Dr. Jonathan Parsons, a pulmonologist at The Ohio State University Wexner Medical Center. ”This excess mucus can drip........

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