I always have the urge to eat. not just a snack but a huge meal. i never seem to get full. i always think about food. what could this be from?

Mysterious: When this is new, your physician needs to rule out an insulinoma. If this is lifelong, my own thinking is that it is primarily genetic -- the psychology folks may disagree, and of course many factors come into play. The key is what we're going to do about this -- your physician has several options for you, and you may be offered bariatric surgery. Best wishes & thanks for asking.