Heart stops.
Wrong.
Current conventional common wisdom: smoking.
I made a curious discovery a number of years ago, perhaps 10 or so years past: in a discussion similar to this one there was a list of the modern 10 longest-lived persons, and their documented age.
All of them smoked most of their lives, with three of them smoking past age 100.
Ironically it occured during the "smoking" hysteria and the monumental penalty extracted from smokers in the U.S. via the tobacco companies.