(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

Biological aging is made of the following:

– Telomeres shorten over time. Telomeres are the end-caps or ‘shoelace tips’ protecting the DNA in your cells. The Telomeres are used up a little bit every time a cell divides. Once the telomere is worn away entirely, that cell can’t replicate anymore, and is essentially ‘dead’

– DNA damage buildup. The sun’s rays, viruses, and various chemicals damage your DNA. When your DNA gets too damaged, your cells cant replicate, or they replicate mutated and cause cancer or other diseases.

– Gene expression errors. Your cells arent reading your DNA correctly and you’re getting harmful mutations.

– Cells don’t die when they’re supposed to. As a side-effect of mutation or damage, sometimes cells dont submit to the natural maintenance cleanup and refuse to die. They keep using up the body’s nutrients, sitting around doing nothing.

– Energy production cellular marchinery malfunctions. Cells dont get enough food/energy/nutrients and die faster than they can be rebuilt.

– Inefficient cell communication. Due to damage accumulating over time, communication systems within the body break down, and cells can’t tell each other what they need. Like, your liver’s broken cell phone can’t tell your gut ‘hey we need more sugar down here!’ and never get that sugar delivery, and so cells die.

– Stem Cell exhaustion. Stem cells can turn into any other cells, and are important when healing damaged tissue. If you have no stem cells, your healing goes to shit and your little cuts never seal back up.

—

All these things build up over time.

Due to accumulated damage, random mutations from sun radiation, and a breakdown of cellular processes, the body shows signs of ‘aging.’

And eventually your cells get so shitty at doing their job that a minor infection from a cut on your leg can’t be stopped, and it kills you. Or one of ten-thousand other ways ‘cells just not working’ can kill you.