I fantasize about this. Ok, bear with me, this is really satisfying to think about. I fantasize about this every time I see someone complaining that "genetics" has caused their fattitude. It would be fun to write a book or screenplay. Imagine a world where this technology exists: Humans can swap consciences for weeks at a time, meaning I keep my brain, but my body trades with someone else. Among the many applications of this technology, a TV show emerges where fat people trade bodies with "fat people haters" with these rules in place: I fantasize about this because it would absolutely eliminate people who can magically defy basic rules of thermodynamics. Anyone who claims that they can't diet, or that they gain weight while consuming only 400 calories a day, would be met with tons of opposition, not "just love your body! You look great!" but rather "huh? really? then why don't you go on that show and make yourself some pizza money?" There would finally be a way to definitively prove to people that their size is a direct result of their bad decisions, and fat people would disappear. Any fatty who managed to walk away from that show with money would face a ton of "challengers" who would be willing to double the odds and prove physics right. Realistically, the show would be cancelled after just a few episodes, because all fatties would finally admit to themselves that they CAN lose weight, if they're motivated enough. None of them would go on the show anymore, just to be shamed in front of a worldwide audience, in the most embarrassing way possible. (GPS locators would be injected into the thin bodies, to keep fatties from running away.) Thin people could make good money this way, as long as they're willing to live in a disgusting pig body for two weeks. If their body comes back in terrible condition, they can spend part of their $10,000 on a gym membership.  We would go from millions of fat people and their excuses, to just a few thousand and their "that show is rigged!" comments. People would start to be ashamed of their fatness again. There would still be fats who genuinely don't care that they're fat, but they would know for a fact that if someone else took over their body, they wouldn't be fat anymore. The entire "body acceptance" narrative (as it applies to fatness) would be blown to pieces. Ah, but that will just have to remain a dream.