Why does caffine keep you awake?

Why does caffine keep you awake?

Chris Idzikowski (Director of the Edinburgh Sleep Centre) gives expert video advice on: What lifestyle choices can affect sleep?; Can certain foods make you drowsy?; Can alcohol make you sleepy? and more...

Caffeine's an interesting compound in that people vary in how they react to it, and people within a lifespan can vary. An example is women who are pregnant may suddenly react very badly to having caffeine, and then after can drink it again. It's a complicated compound. It probably impacts mainly on the wakefulness promoting system. It doesn't actually cause <a href="http://www.videojug.com/interview/the-effects-of-sleep-deprivation-2">sleep deprivation</a> by switching sleep off, it just makes you more alert.