The other issue is accumulated toxic damage we cannot fix at all. When did we phase out leaded petrol? (We haven't fully, but you get the idea...) When did pe

The other issue is accumulated toxic damage we cannot fix at all. When did we phase out leaded petrol? (We haven't fully, but you get the idea...) When did people mostly stop smoking carcinogens and heavy metals? When did we start, or stop, using toxic azo dyes for clothing? Or particular fireproofing or plasticizing chemicals that are endocrine poisons? Or the latest plague, which hit a lot of people in the brain? While any of those things is not predictive enough at individual level due to genetic variance, statistics of big numbers show delayed correlations that heavily imply causation, while high dose studies show obvious toxicity of this kind. And when such chronic damage happened 20-30 years ago there's not that much our medicine can do yet. We cannot even reactivate a thymus (major gland of the immune system) well yet en masse. Or fix or reliably help livers.