Extreme method of weight loss

I remember a friend of mine from my college days. Though actually we met through science fiction fandom. He just lived in the town where I went to college. I never would have met him otherwise, since he was older and out of school and working.

But he had a tremendous weight problem -- was definitely the largest person I've ever known. He either didn't or couldn't diet, and so for weight loss his doctor eventually recommend he have intestinal bypass surgery. I don't think his digestive system ever recovered from it.