Most regular superhero books are designed to go on forever; of course, very few of them do, but the point is they are trying to throw mud against the wall and hope it will stick, and most of it slides off.
I don't feel any pressure to lose weight - and in any case, if I didn't have my food I'd be a nasty piece of work and wouldn't be able to function.
I think if you're a competent actor with a good imagination, and if it's on the page, it makes your job a lot easier.