One of one bosses I worked for, I heard he told his wife that he wasn't feeling okay, and he went to the hospital and that was the day he died. Life is about management, if you manage your symptoms and take care of yourself, manage your issues well and even prevent them before they happen, then a person stands a chance. 

While we're not God, it's important to be proactive, if I was proactive about myself in my younger years, maybe I'd have done better, but I'm grateful to God nonetheless