Now I have a little more time on my hands.
1. The average life expectancy on Earth is not 80 but under 70.
2. 40 does not go into 80 3x
The reason the average life was lower in the past in comparison to today is the fact that their was little to no scientific research and developement of things like vaccines which are making us live longer. Old diets were much better than ours currently and your adjectives show just that. To make sure we are on the same page and to clarify, diets of the past did not make them live a shorter life and our current diets do not make us live longer. It is the X factors that play the major role here. It is a fact that lifestyle dieseases are increasing at an unseen pace. We have more control over this than say polio or MMR. Sorta like Ldub said our immune systems are not what they should be since we are not exposed to the same as our ancestors. The mentioned hormones are just one reason that we become ill. All of this further solidifies the idea of supplementing what we consume in order to prevent. Its not a hippy lifestyle, it is simply science and techonolgy.