See, when these people say "unrealistic" what they really mean is "unrealistic without major lifestyle changes." I've dealt with LOTS of fat people along with other sorts of addicts, and these people get so hardwired into eating like shit and being lazy that an actual healthy lifestyle seems like strange voodoo to them. That's where you get shit like fats sharing a 15 minute workout or walking a 5k and treating it like they did a marathon, their standards of what being active is drop to nothing.