It's involuntary, it's almost impossible to resist, and it spreads faster between people who are close to each other than between strangers. Contagious yawning isn't boredom. It's an old mirroring system.
Sometimes your body knows before your brain does. The stomach drop that hits right before someone tells you the bad news isn't dramatic imagination. It's a real, fast warning system, and it's older than language.
It's not really about the taste. Comfort food works because, somewhere along the way, your brain learned to connect certain foods with being cared for.
The chest pain, the appetite loss, the feeling that you've been hit by something. Heartbreak isn't a metaphor. Your brain processes it almost exactly like a physical wound.