...yep its a big worry to someone like me too...but i go with Paul no matter what you do to your body when your time is up its up..unless of course you abuse drugs drive too fast you know accident wise.
You can prolong your life though by regular heath checks if you feel you come from bad stock. We got a new hospital goin up next to us at work that does that body screening where it can tell wether you are gonna have a heart attack within the next 5 years or the start of cancer etc

Talk about playing God!!!