Coffee and sleep. Two things that humanity has not yet decided what is more pleasant. But what humanity knows 100% is what effect caffeine (in any form) has on the human body, and especially how caffeine affects the quality of sleep.   

So how does caffeine work and how does it disrupt your sleep?

Caffeine is a substance that we classify as a psychoactive stimulant, thanks to which you can remain alert, attentive, and energetic even if you have slept for a short time. This is because caffeine blocks adenosine receptors, which causes drowsiness when your receptors are full in your brain. Caffeine has a similar molecular structure, allowing it to effectively block adenosine receptors. 

*Addiction alert* but when receptors are still blocked, the brain creates new ones. This, in turn, forces us to drink more and more coffee and fundamentally affects our decaffeinated functioning.

Matthew Walker, the author of the book Why We Sleep, claims that caffeine affects your sleep in several different ways. Being a stimulant, it is likely to cause you difficulty falling asleep or waking up from sleep.
Undout Sleep Box coffee caffeine affects your sleep
Caffeine works much longer than people think. We know that caffeine works partially after 6 hours of consumption (half-life of 6 hours), but what we don't talk about is that after 12 hours, a quarter of the caffeine consumed is still in our body. It basically means that if you drink a cup of coffee around noon, it's like having a quarter of a cup at midnight before bedtime. Which is a problem for most people.

But what if you drink a cup of coffee for dinner and fall asleep without any problems? It is true that enough people have some immunity to caffeine, and they will not cause them any problem with falling asleep or waking up during the night. However, one cup contains about 150-200 mg of caffeine, an amount that reduces the length of a deep sleep by about 20 percent.


Whatever you can imagine, according to Matthew Walker, in order to achieve this reduction naturally, you must be aged 15 to 20 years. Or that coffee… 

The decaf doesn't sound so bad anymore, huh? 

But how can we drink coffee so that we can benefit and not ruin our sleep?

  • If possible, avoid caffeine after 2 pm.

  • Try drinking sugar-free coffee.

  • Use quality, ideally organic coffee.

  • Try not to exceed the recommended amount of caffeine (according to Health Canada 2.5 mg per kilogram body weight). That's usually up to 4 cups of coffee for an adult.

  • Avoid synthetic or low-fat milk.

  • If you drink “turkish”, start using a paper filter or perhaps different alternative brewing method.

    We hope you have gained some new knowledge about the impact of caffeine on your sleep and perhaps learned how to use it in a more effective and healthy way.


    Sources: TED-Ed, Matthew WalkerSleep Foundation