A change of diet would help him too, more fresh. I grew up eating terribly because of the way my mother cooked (or rather heated up something from a can or package). I really didn't know any better, maybe he doesn't either.
Health crises require consistency. Perhaps he would be willing to be consistent if you were willing to guide him a little.
Does he drink diet soda? Diet soda floods the system with amino acids that are then found in the urine (proteinuria), according to Dr.James Balch, Prescription for Nutritional Healing.