I go through this. Partly with me it's family history -- My Dad only ate two meals a day and we ate a very big dinner, especially on the occasions we went out to eat. As I grew up, I've gone through different stages, but when I started suffering anxiety and depression, I got isolated and ate a lot. I also exercised a lot so like you I didn't get fat until medication made me gain uncontrollably. Some of us can eat a ton without gaining a lot at least until we get old. So at least for me, eating became something to do that was intense to replace all the intense things I was passionate about that I started avoiding because of anxiety and depression. I call it now a kind of bulimia, in a way -- you eat, then purge by not eating or perhaps forcing yourself to go the bathroom or exercise compulsively -- lots of things we can do besides vomiting to sort of purge. I guess the cure is, to not feel or be so isolated because of your illness, which is hard because it means tackling your illness head on which is the very thing anxiety and depression push us to avoid. I would recommend, if you haven't done it or aren't doing it now, that you get into therapy and try to figure this thing out, and in the meantime, try and keep yourself absorbed in things the way you probably did before you became depressed -- in short, try to end the isolation and avoidance that is the essence of your illness through sheer will, if you can. What you don't want is what happened to me, which is a body full of pain as I'm in my Sixties and all that exercise and lack of sleep caught up to me and a lot of teeth problems. Good luck.