>Another may be that we
>are trying for levels of health and vitality that are higher than
>what was "needed" for our bare survival.

Yes I think we are doing exactly that, and that we are completely justified
in our attempts to achieve health and vitality greater than that which was
needed for our survival. More accurately, we are justified in seeking ways
to achieve health and vitality greater than that which was necessary to
perpetuate our genes. Our survival as individuals is not the "goal" of
evolution. The only "purpose" for our existence is to perpetuate our genes
to the next generation.

(Like you I use quotes because it is difficult to speak of a "goal" or
"purpose" of evolution when evolution does not in reality have purpose, but
I will stop with the quotes because it makes for awkward reading.)

In evolutionary terms, living organisms are merely gene perpetuating
machines. As Richard Dawkins made so clear, only the survival of the *gene*
is important; the survival of the organism is completely irrelevant. The
praying mantis knows this very well. The female devours her mate's head,
which he gladly sacrifices as food to help nourish the fertilized egg.

This means that the forces of evolution.. natural selection.. have
engineered our bodies to work well until the age at which we likely to have
procreated. Nature's implied warranty gradually becomes null and void with
each year that passes after our sexual prime. In fact there is good reason
to think even that we are genetically programmed to break down and die.

We are like astronauts aboard carefully engineered rockets designed to be
launched into orbit to achieve some end, for example the photographing of
the earth. After we have achieved our goal, we become mere space junk. The
engineers and technicians down below (mother nature/natural selection) are
no longer concerned for our fate and we would be foolish to place all our
trust in them. As astronauts aboard that abandoned space ship we are very
wise to use every resource we have available to us to maintain our health
and longevity. Vitamins, including megadosed vitamins, are one of those
resources. Smart drugs, hormone replacement therapies, other
pharmaceuticals, etc, these are all legitimate tools at our disposal. We are
under no obligation to go quietly into that dark night.

-gts