(or 2!) Dying of old age, can you actually DIE because of the body being worn out, or is it always a disease or such? I read that if we cure every disease, we would live hundreds of years.

Question

Title! I don’t get it. Isn’t my finger getting worn from just being used for too long? Or will it eventually get worse because of something else?

In: Biology

Answer 1

No one dies of ‘old age’. There’s always a more proximate cause. Not sure I can ELI5. I can ELI15.

For those who die of “natural causes” in younger elder years (50-80), usually because either cancer (a common malady of all multicellular long lived organisms) or because the immune system is too active in responding to to insults of Western lifestyles. That heart attack? That’s inflammation from lifelong high fat diet (macrophages expressing MMP9 to break down fibrous covers of vascular walll cholesterol buildup).

In older elder years (perhaps 81-120), death is more commonly a result of inadequate immune response, because immune stem cells hit their Hayflick limit, and can’t respond to infection.