How long can my cat live with worms.?

My cat has worms and I am wondering how long he can live with them. They don't seem to bother him that much, in fact he actually enjoys them I think. He poops them out then eats them creating a self sustaining life cycle for bot worms and cat. Im even thinking about not feeding him anymore because he is getting pretty fat off the worms, and that doesn't seem very healthy (a fat cat...ewww). How long do you think he can live with this smorgasbord of worms?