It could be argued that smoking, alcoholism, and obesity are all means of coping with a high stress lifestyle. I wonder how many more people would die from other reasons if they were no longer able to use those coping mechanisms. Or maybe more importantly, how much total happiness would they have in their life if they had the extra time. I say this as a fairly recent cancer survivor if that matters.

edit: Does anyone know if psychologists or sociologists have a formula for quantifying happiness? Something like mechanical advantage. It seems intuitive that certain behaviors can act like a fulcrum by increasing happiness now at the expense of sadness later, either born by you or those close to you. I'm sure we've all had smokers joke that you can keep the last 20 years of life, maybe they're on to something.