People aren't overweight because of genetics. To say so is indeed bullshit. Genetics do however play the deciding role in which body type you end up with and endomorphs do have a much easier time getting overweight. Still, just because you're an endomorph you shouldn't use it as an excuse for overeating and not taking proper care of your body. Besides, EVERYTHING isn't stacked up against you. Endomorphs generally have better hair, smoother skin and much more attractive facial features so stop thinking you're some kind of victim due to your bloody genetics.
Anyway, isn't this whole discussion slightly off-topic? Not that anyone gives a shit. We're in the Naruto forums after all.