I agree that good health, which may give us the ability to live longer and enjoy life more is definitely a combination of good genes, a healthy lifestyle, (diet, nutrition, exercise) and a positive attitude (including minimizing stress)–hence the premise of the mind-body connection as mentioned.
Personally, I also believe that, at the core of the matter, you need to feel you have a purpose or a variety of reasons for living–whatever they may mean to each person–and imo, that is the engine that drives the other aspects.
Our family and extended family (including parents and grandparents) have pretty much operated on those premises for as long as I can remember–and since most of them (even the ones who received a serious diagnosis at some point) all looked at least 10 years younger than their ages (without intervention) and ended up living long and fulfilling lives–we’re just trying to follow their great examples.