With Every Breath
Oxidative Stress and
It is now beyond question that caloric restriction can have a profound impact on both average and maximal lifespan. But how are we to explain this effect, which can be observed in virtually every species? We could imagine that animals reared on a calorically restricted diet are simply healthier, and as a result live longer. That could perhaps explain the increase in average lifespan, but it is not at all obvious how such factors could affect maximum lifespan, which, to the extent that it is genetically determined, would not be expected under normal conditions to vary on anything less than an evolutionary time scale.
If the conclusion stated at the end of the last chapter is true, that what the caloric restriction experiments are telling us is that overfeeding may prevent us from realizing our true maximum lifespan, then it may well be that in these experiments we are touching on something very fundamental to the aging proccess. We have said before that in order to understand aging, we must search for basic senescence mechanisms