In honour of International Coffee Day, we swan dive into the coffee nap, biology’s way of telling you it’s okay to be alert, but also asleep.
Coffee and naps. Undoubtedly two of the greatest things known to man, until you put them together and it’s like women and the Liberal Party: it just doesn’t seem to work. But, while anyone who has ever crammed for an exam knows that caffeine disrupts sleep, it turns out, there’s a way around it: if you down a double espresso and then climb under the covers for no more than 20 minutes, you can actually maximise alertness when you wake up. It sounds crazy, but don’t worry: there is science to back it up!
The way coffee works is that once you sip that sweet, roasted goodness, it goes through your intestine and into your bloodstream where it crosses into your brain. From there, it meets with something called adenosine, a totally normal chemical we create just generally by being awake and attempting to function throughout the day. But you get too much adenosine, it makes you feel sleepy. Again, totally normal: it’s your brain’s way of telling you to stop mindlessly scrolling Instagram and turn out the light. The cunning thing about caffeine, however, is it has kind of the same shape as the receptors that adenosine usually fits into. So it butts in and takes over and fills the tired spots so you don’t feel sleepy anymore. There’s only so much caffeine can do, however. It’s not like Putin – it isn’t omnipotent. This is why you can knock back a coffee and still just feel like death: caffeine blocks some of the receptors, but it can’t block all of them.
This is where the power nap comes in. When you nap, you naturally lose adenosine. But here’s the thing: if your nap goes too long, you get into deep sleep which is fine if it’s midnight and you’re on the couch with the dog, but not so good if you’ve curled up under your desk during your lunch break and you’ve somehow gotta be alive for a 2:30 conference call. And while there’s nothing better than a nap, there’s nothing worse than waking up from a nap that accidentally went too long and wondering who you are, where you are and what year it is.
Hence the beauty of the coffee nap, which is all about timing. Conveniently, the time it takes caffeine to get into your brain is exactly the same amount of time that constitutes the perfect nap. (Isn’t biology clever?) So if you can manage to throw back a flat white and then crash before the caffeine gets to your brain, you’re a winner winner espresso dinner!
Your adenosine levels will drop while you snooze and then the caffeine will hit you when you wake. There’ll be less adenosine for it to fight with (because you lost a bunch during your beauty sleep) and so the coffee will be even more effective in getting your brain working.
As for how much coffee you should be drinking? Most experts reckon about two cups, quickly before sleep, is the way to go. But if you’re anything like me and there’s no way you could possibly fall asleep on cue and keep your naps to a mere 20 minutes, never fear: the same study that decided two cups is all it takes also concluded that even if you can’t fall asleep, just letting yourself rest and get a bit dozy can make a huge difference. Scientists haven’t been able to look at the brain itself during or after a coffee nap so a lot of this is all hypothetical based on what we know about how our noggins work – but there have been a bunch of human studies done, like one which examined sleepy people in a driving simulator.
Half took a 15 minute coffee nap while the others did one or the other and – no surprise – the coffee nappers performed better upon waking than all the others. Another study kept 24 men awake for 24 hours with nothing but 15 minute naps to break up their day. Half were given a caffeine pill and took “coffee naps”, the other half took nothing. Again, no prizes for guessing who performed better: the caffeinated performed almost as good as they would have after a full night’s sleep.
So there you go; lazy caffeine junkies of the universe unite: we may have Trump, superstorms, bushfires, sexist jerks in parliament and any number of other terrible, horrible, no good, very bad things to deal with, but at least we know we’re allowed to have our cappuccino and nap too.