Metabolism is a word that is talked about a lot when you bring up dieting. Yes there are people who can eat a lot, and do not seem to gain much weight. They are of course either burning it up in their daily activities, or their bodies are simply passing all that food through them, and it's ending up in the toilet. The question you need to ask yourself: "Is all that extra food/fat intake finding it's way to the lining of your arteries, even though it's not creating a spare tire?"