system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that after eating spicy food, eating hot (as in temperature) food is so much more painful?
gpt
Capsaicin (the thing that makes peppers spicy)   makes the TRPV1 protein activate and sends "this is hot" siignal to the brain. TRPV1 is the same protein that sends the signal to your brain if you burn your tongue or touch a hot stove. 

So to your brain, you're burning something that's already burning... Making it hurt worse :)