Good health is all about quality of life. If you smoke you are highly likely to die of COPD. If you drink too much alcohol you can get chronic pancreatitis which is horrible. In another sense if you like to play sports and you like to win then be in better shape that the opponent. I di Jiu Jitsu and like to strangle people, if I was a fat piece of shit I would be the one getting choked out. Easy