Dr. Bischinger has been quoted as saying (in an Austrian accent), "With the finger you can get to places you just can't reach with a handkerchief, keeping your nose far cleaner. And eating the dry remains of what you pull out is a great way of strengthening the body's immune system." He then added, "Medically it makes great sense and is a perfectly natural thing to do. In terms of the immune system the nose is a filter in which a great deal of bacteria are collected, and when this mixture arrives in the intestines it works just like a medicine."
"Modern medicine is constantly trying to do the same thing through far more complicated methods, people who pick their nose and eat it get a natural boost to their immune system for free."
Picking your nose and eating it may be beneficial to your immune system. A study done by Stefan Gates stated that 44% of adults admitted to picking their nose and eating the dried mucus. The even grosser part was they said they liked it. Gates comments that "our body has been built to consume snot," because the nasal mucus is normally swallowed after being moved inside by the motion of the cilia
Mucus filters airborne contaminants. Eating it helps our immune system become stronger and learn to fight off all those contaminants. We swallow a lot of our mucus anyways through the nasal passage down the throat.