The more I think about it, the more I think they have confused an episode of Aqua Teen Hunger Force with a diet video:
Carl before the South Bronx Parasite Diet:
Carl after being on the South Bronx Parasite Diet for a while:
Carl after after being on the South Bronx Parasite Diet at it's inevitable conclusion looking buff:
It turns out that many news stories these days are mistaken recaps of Aqua Teen Hunger Force episodes. I don't know how it happens, but it does.