I was going to mention that comics pros from the 1970's and earlier weren't the rotund pigs we've seen from the 80's and forward, but then I realized that was probably because they couldn't afford food.
The Golden Age comics guys all lived around New York City, where the publishers were, so they spent a lot of time walking.
And also, yes, some of them were probably starving. Jack Kirby
was skinny so that Joe Quesada
wouldn't have to be.