Your nose makes about 1 liter of mucus a day, most of which you swallow





A normal amount of nasal mucus and fluids released per day amounts to about 900-1000 milliliters or one liter. These fluids are designed for filtering and heating of the inhaled air you. Although a small part of the discharge you get rid of, for example, when you sneeze, a large part remains in the body, flowing down the back of the throat. Not too pleasant fact, but still - a person can not exist without swallowing their own snot, even if he is not sick.

via factroom.ru