Somewhere I read that Adam the first man created by God lived about 930 years.
If so, this means that gradually any technological advancements (starting with primitive items), along with diseases, brought the average life expectancy say in Japan (which is highest of other nations) about 82 years.
We know that cancer is more than 3000 years old.
This question must be related to our space research!
Why? Because bringing in clean energy from outer space, making technologies there and transport it to the Earth, as well as use of other minerals there in any form, may reduce our diseases and hopefully, we may have longer life expectancy.
Even we assume statistics about environmental pollutions are manipulated by politicians, still man caused pollution is certainly partially believable.
No doubt, there is another disease in our societies, which I have noted in my book, which is huge income inequalities, without adequate social programs, like health care, particularly in the USA.
I noted earlier that because of forces outside of the centroid position on the Earth, we have no life, even if we find water in some planets.
Indeed forces may not even create molecule chemistry of water i.e. 2 hydrogen element and one oxygen element as often told by the media.
I hope space researchers and politicians (Particularly 2016 US election) note this fact that, in the next 40 years we need to address severe earth problems by our space research .
And mathematics, particularly DNA of mathematics plays an important part in this initiative.
I strongly believe that mathematical research on DNA Riccati level coupled with research on cells within medical research levels, will be a right course of action in this regard.
We will be alone on the Earth for many thousands of years unless we find a way to bring fresh resources and clean energy from the nearby plants.
Dr.Mehran Basti Basti05b@aol.com
PS: Evils such as "atomic pollutions, world wars, racial hatred," etc. are noted in my book.