I believe radiation is the number 1 cause of ageing...and who experimented with radiation for war purposes and what profession uses it for medical purposes...those 2 groups of wealthy/greedy/power hungery people can't stand any peasant living past age 40 now...................and as Nature goes, our earth is nearing the end of its cycle that will kill everything and then start a new cycle...............in the beginning, all will live on pure air alone and as the cycle goes, radiation will be the major cause for shortened lifespan....that is my opinion.
but regardless, if a human can live to age 250, then by golly, we all have that ability and that points at diet and habits.