well case not closed, actually far from closing:
'
The Role of Genes Versus Environment in Aging and Exceptional Longevity. Gerontologists often cite studies of lifespans amongst identical twins reared apart to describe the genetic and environmental components of aging. Based upon these studies, the common answer is 70-80% environment and 30-20% genes.'
again:
https://www.bumc.bu.edu/centenarian/overview/
Cancer... runs in families
Hypertension... runs in families
Heart disease... runs in families.
Dozens more, those are just the big 3.
So if you do a study of two twins and they come from one of the above...
Twin #1 one lives life like Freddie here... (that's a compliment Freddie) or Baron (ditto on the compliment)....
But twin #2, he or she eats crap, drinks like a fish, both alcohol and soft drinks, and smokes a pack or two a day.
Twin #2 dies at 64 of a stroke.
Twin #1 dies @ age 72.
Study confirmed.. it's all about lifestyle.
Except.... twin #2 died of cancer.
Through no fault of their own.
Then there's the next door neighbor whose family has none of the above and lives a life somewhere in the middle of twin one and twin 2... ahhh... probably leaning a little more towards a twin #1 lifestyle as they roll into their late 60's or early 70's... wisdom sets in... and they live well into their 90's.
A 30% increase... and that's a big deal.
So its just like everything else... there's a 100 ways to run a study.
Desired results are easy to achieve.
I won't "close the case"... but my money's still on genetics.