I've eaten at the Big Texan several times, but I've never been tempted to try the 72-ounce challenge. I think the biggest steak I've ever eaten was about 22 ounces. 72 just would not happen. That's 4½ pounds of meat.
The stomach of an adult is about the size of a fist. Well, that's for a normal adult who rarely ever eats a large meal. For most Americans, what with the portion sizes being what they are, the stomach is stretched out to be about the size of a small cantaloupe. Interlock your fingers to make one big fist. That's probably closer to the size. Sure, the stomach can stretch up to 80 times its normal size when consuming a large meal or a large liquid intake, but a 4½ pound piece of meat, and all the trimmings? That can't be good for you.