I’m not quite sure, maybe I’m making this one up because I can’t really remember much more, but wasn’t there an episode when cartman tries to eat healthy food and then something bad happens to him. Like he’s getting an allergic reaction or just sick. Then someone, maybe a doctor, tells him and his mom that he can only eat fastfood because his body got used to it. There might be a chance that something like that happened in another TV show. Anyway, thanks for trying to help 😅