Gut: The Inside Story of Our Body’s Most Underrated Organ

by Giulia Enders

Those tiny particles can enter the lymphatic system, embedded in fat droplets, and once there, they attract the attention of ever-vigilant immune cells. When the immune cells discover a tiny particle of peanut in the lymphatic fluid, for example, they naturally attack it as a foreign body. The next time the immune cells encounter a peanut particle, they are better prepared to deal with it and can attack it more aggressively. And so it goes on, until we reach the stage where just putting a peanut in our mouth causes our immune cells to whip out the big guns straightaway. The result is increasingly severe allergic reactions, such as extreme swelling of the face and tongue. This explanation applies to allergies caused by foods that are both fatty and rich in protein, such as milk, eggs, and, most commonly, peanuts. There is a simple reason almost no one is allergic to greasy bacon. We are made of meat ourselves, and so we generally have few problems digesting it.