I bet all of those digestive and health issues he has are self inflicted. He has an eating disorder, it's just not the common ones like Anorexia or Bulimia. We might be diagnosing a new eating disorder, that might directly tie into the bodybuilding lifestyle.
His desire to stuff himself full of calories, with no regard for the health aspect of said food is definitely a mental disorder of some kind. The fact that he has turned a blind eye to his body's constant rejection, and cries for help, only further substantiates my theory.
Guy needs to put down the fork and see a therapist.