You've hit the nail on the head, pointing out that fear reaction. Fear of losing control is kind of funny when you think that people don't really have much control to begin with. We've got heredity, and happenstance, and we've got patterns of dealing with food that are learned at our parent's knees. These may allow us leeway for modifying our behavior to some extent, but they are always going to be exerting their influence, however much we think that we're in charge.