This is a great question and I have often wondered this myself! Basically I think it has something to do with inheritance and blood line factors which give certain people an "edge" over others AND gives someone a predisposition to have or not have health problems in a certain "area". For the most part I don't think these people really end up getting away with living their unhealthy lifestyles. It ends up being expressed some way some how at some point in their lives i.e. cancers, female issues, bad breath, hair loss/balding, anger & bitterness, depression, fatigue, diabetes, mental illness, constipation, digestion problems, etc. I think we sometimes think people aren't afflicted with anything esp. when it's not a visible thing like acne, but many are. These are also some of the same people who believe an illness hit them right out of the blue, but it was really something that was building for a long time.