For some, foods that generate pain can trigger an adrenaline rush, similar to watching a horror movie.
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In both cases, the brain can override the initial pain reaction. Paul Rozin, a professor of psychology at the University of Pennsylvania, attributes this override to humans’ ability to differentiate between serious and “benign” pain. Eating moderate amounts of spice is generally safe, he said, but even so, the body treats it as a health threat.
“That’s where the pleasure comes, from the fact that you’re overriding your body’s signal not to do this,” Rozin said.