Biology · Caffeine’s trick

How does coffee keep you awake?

Name: How does coffee keep you awake?
Uploaded: 2026-10-25
Duration: 22 s
Description: All day, your brain makes a molecule called adenosine. As it piles up on its receptors, you feel tired. Caffeine has almost the same shape. It slips into those receptors and blocks them, so the tiredness signal can't land. You don't gain energy, you borrow it: when the caffeine wears off, the adenosine is still waiting.

What you’ll see

All day, your brain makes a molecule called adenosine. As it piles up on its receptors, you feel tired. Caffeine has almost the same shape. It slips into those receptors and blocks them, so the tiredness signal can't land. You don't gain energy, you borrow it: when the caffeine wears off, the adenosine is still waiting.