For additional info, I had a pretty serious endocrine problem that the Navy never figured out, but a civilian endocrinologist sorted in about three visits. That's all sorted, but I have to work at losing the weight like I gained it by being a sloth.
I had always been super active, racing motocross, mountain biking, running 10ks and half marathons, spartan races, etc.. But I was pushing 320 pounds and if I cut my caloric intake I'd pass out from low blood sugar. That is what the endocrinologist fixed. The diet is because I got sick of walking around being the strong guy who is scary fast for a fat kid. (I can run a 5:30 mile, which is fast for someone my size) I can probably push 5:15 right now, and am trying to go sub 5:00 like I could in college once I get back to my "normal" (pre-endocrine isuue) size.
I had been slowly dropping weight since that was fixed, but it was coming off slow eating reasonable even when I was doing an hour of HIIT training burning 1k calories 4-5 days a week and working out on every layover.