Once upon a time, there were at least two kinds of people in the world: Those who drank coffee for its delicious taste and alertness-giving effects, and those who stayed away for fear of it interrupting their sleep.
Recent studies suggest that life doesn’t have to be this way -- at least when it comes to nap-takers.
In fact, consuming a cup of coffee shortly before a power nap has been shown to improve the effects of the nap, providing for more alertness afterwards than coffee or a nap alone can provide.
The science behind the “coffee nap,” as it has come to be called, boils down to how sleep, caffeine and a drowsiness-inducing chemical called adenosine work within the human body.
Each hour we are awake, levels of adenosine rise in the body, which gradually work to make us seek sleep. When we are finally asleep, that buildup of adenosine is cleared away.
This relationship between sleep and adenosine combined with the fact that caffeine’s effects are delayed by 20 to 30 minutes are what makes coffee naps so effective, .
Caffeine and adenosine compete for the same receptors in the brain, so when adenosine is depleted during a nap, this effectively means that there are more spots open in the brain for caffeine to take hold.
So if you drink a cup of coffee and then sleep for 20 or so minutes, you will have effectively supercharged your caffeine intake and your ability to be alert and focused post-nap.
And you will have done this all while sleeping.
Researchers at Loughborough University in the United Kingdom were some of the first to disprove this myth that caffeine and naps don't mix.
Before you go ahead and try this yourself, be careful what you put into your coffee.
"Drinks with a very high sugar content can worsen sleepiness," according to the UK researchers.