system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What does caffeine acctualy do to your body in order to keep you awake?
gpt
There's a molecule called Adenosine. As you go longer without rest, it builds up in your nerves. If adenosine were to dock with adenosine receptors, you would feel drowsy and tired. Caffeine comes in and docks with the adenosine receptors, preventing actual adenosine from binding to them. No binding = no sleepiness and more alertness.


Over time the caffeine you have is metabolized or gotten rid of, and you get tired again.