Back in the early 90s, I went to the Dr for my physical, he told me if I quit, I'd live forever. I quit then and there for three years with no problems(aside from the incessant reach for the absent pack of smokes, then reminding myself (a lot) "you don't do that anymore").

...but I started again, now pushing mid 60s, and really need to quit...gotta get that will power thing going again...I've done it before...