Just like most of the rest of your body, the stomach will adapt over time to fit your needs. The capacity a stomach can hold is based on volume, not on weight. which means if you were to eat very dense foods or liquids, you could very well hold more than 2.5 pounds of food in your stomach. at the same time, while the average person's stomach might hold 1 quart, that is not true for everyone. The stomach will stretch out over time if you consistantly fill it. For instance, I know for a fact that my stomach can hold well more than 1 quart without forcing me to throw up, since on plenty of occassions I have drank a half gallon of water in under 10 minutes with no problem. There is also some theory that this stretching is part of what makes weight loss difficult for much larger people. Since the stomach has stretched and enlarged, it takes more food to fill it up. There is the possibility that when a large person tries to cut down their intake, they get feelings of hunger much more easily than the normal person because relative to the size of their stomach, it is not full. the stomach will send signals to the brain that it is running low, and then the brain interprets that as hunger. Like i said though, this is just theory as far as I know.
