all fat people are substance abusers.  This. There's pretty good evidence to support the idea that obese people are essentially sugar addicts (can provide a link to a great summary, if anyone wants). There are quite a few parallels to how fat peoples' brains and coke addicts' brains look, as well as in how they respond when presented with sugar or cocaine, respectively. Part of being an addict - the main part, really - is the desire for your substance of choice above ALL else. This often ultimately ends up including family, friends, the addicts' own physical safety and mental well-being, hence the behavior some might see as sociopathic. The only part that isn't similar to addicts is how fat people just don't make the connection that their eating habits are ruining their health, whereas a drug addict usually does, but just can't bring themselves to stop using. The only theory I have for this is that there are crossed wires in fat peoples' brains, where they get stuck with the impression that eating tons of crap is the only way to eat. To survive, they'd have to learn to moderate their eating, because they can't just not eat, obviously, and most addicts aren't known for their ability to moderate themselves.