Heart age
There are so many factors at work including genetic predisposition s for contributing factors.
Personally I consider a major factor for me in keeping my 'heart age' low is the old saying ' You are only as old as the woman you feel'.
My current and first wife are both 18 years younger than me and few people believe I am the age I am.
Over four decades of martial arts helps as does not drinking to excess, when the bottle is empty I rarely open another.
Another major factor is not having a phone number for a doctor, so no home visits for me, those guys are dangerous!