[Dextor]

I have the exact same problem. I just eat and eat and eat! It's annoying because it also stops you from gaining weight and muscle. I have this thing called Ectomorphism, which means I find it extremely hard to gain weight and my metabolism is very fast. I tried researching before, and I don't know if you can actually make it go slower, but if you're looking to gain weight, apparently body builder shakes are very good. I also read that instead of having three main meals every day, have about 8 small ones, and always make sure the biggest food has lots of protein. Other than that, I don't know.
Hope that helps!