According to Dr. Clinton Bellamy (author, med. doctor, attorney and condiments company owner), the capsaicin in hotter chilis release endorphins in the eater, similar to a "runner's high". The hotter the pepper, the more the high... but just like the narcotic stuff, people develop tolerance to it! Then, you have to eat hotter and hotter peppers to get the same feeling!
Peppers also help boost metabolism... he suggests keeping a bottle of hot sauce on the table to keep your family healthy.
That's so funny - I had no idea. And interesting, because I crave the super spicy salsa they have at El Compadre in Los Angeles and I could never figure out why... I guess this would be it, because that is some spicy spicy sauce!
Cayenne pepper is said to speed up your metabolism as well. It was all the rage here (in the land of skinny) for awhile and it was sold out every time I would go to whole foods. But just think - if you sprinkle super spicy pepper on your food and get super skinny and addicted to the high, you might just end up in Pepper Rehab. It's a vicious, spicy cycle.