Exactly! I had so many patients that would have sudden weight swings after some kind of medical issue, even when their diet was well within healthy caloric intake, and (even worse imo) would have suffered other medical issues had they dropped enough intake to reach their new break point.

It isn't like it's even rare to have one of the dozen plus major medical issues that can cause fat gain well beyond what diet can counter. Hell, host having enough stress can make it very difficult to maintain a healthy diet and still reach one's break point because of how cortisol influences metabolism. And that's without some underlying cortisol disorder. An individual disorder or disease might be rare, but taken together, it starts making up a m Large chunk of the population.