non meme answer? metabolism increases with weight. sometimes people subconsciously overestimate how much they need to maintain their weight, and continue eating more than that. a person of average height literally cannot get over ~350 freedom units unless they are eating 8000+ calories a day without any exercise. i guess they could be some bizarre mutant powerlifter or sumo but we aren't talking about that
if one of those 600+ pound fatties on TLC just stopped eating, they'd eventually relapse and gain all of the weight back because they lost it too fast for the body to retrain itself to eat normally. either that or die from shock. when someone gets that fat you have to gradually and strictly lower intake
but to actually get to that point in the first place
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