Btw for the capsaicin thing. It’s one of the going theories for why warmer places all around earth tend to traditionally eat much spicier foods than colder places. Food spoils faster in the heat, and the spice both masks the spoilt taste and can help, or is thought to help, cleanse you of parasites.

(I know spicy plants don’t grow in colder places, too, but the tendency holds for colder regions that would have had access to hot plants)