system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does salsa get more spicy/hot when heated?

I usually add salsa when making cheese toasties (Bread, salsa + ham/cabanossi and cheese) why does it get more spicy when in the toaster, or oven.
gpt
So Capsaicin activates certain receptors that are sensitive to heat and therefore creates a 'burning' sensation in your mouth. Since these receptors are already activated when you're eating spicy foods, you become extra sensitive to temperature increases, which is the receptor's primary purpose. Your brain has been tricked, in a way, into a false positive inflammatory sensation, so an actual potential inflammatory source (the heat of the salsa) triggers overdrive for receptors that were already activated.