Eli5 why can’t we continuously take caffeine and never sleep?

Question

I work overnight shifts (11pm-7am) and take caffeine pills to stay awake. When I get home, even if I take more caffeine I’m sometimes still too tired and fall asleep. Why does it eventually stop working? Is there some sort of chemical limit? Why can’t caffeine replace sleep for longer periods of time (like days on end)?

In: 595

Answer 1

The purpose of sleep in humans is to do maintenance on the body. Running your body on caffeine acts on receptors in your body but won’t let your body maintain itself. This leads to memory problems and cardiac problems, leading to heightened risk of stroke or Alzheimer’s.