Considering that food is full of foreign proteins, it makes sense that the intestine is the immune system’s version of Grand Central station. It’s the largest organ to regularly sweep up and annihilate molecules that don’t belong. And because food comes from outside, it’s no surprise that some people have allergies to it. The bigger mystery is why most don’t. Somehow during evolution, the immune system and food components developed a secret handshake that allows munchables to pass without a fuss.
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