Caffeine is a sleep killer

By Lise Birk Kristensen

Caffeine is a presentation enhancer, but caffeine should be consumed in moderation as most people underestimate how long caffeine actually stays in the bloodstream and the impact it has on our sleep.

Caffeine is found in many foods such as soft drinks, chocolate, tea, and energy drinks. Caffeine is an intoxicant that affects our mental and physical functions. Research has even shown that caffeine has a direct effect on the central nervous system. However, caffeine also has a positive effect on our health by increasing mental stimulation, including attention and reaction speed. Research even shows that caffeine relieves pain, postpones migraine headaches, and boosts mood.

However, caffeine should be consumed in moderation as it can disrupt sleep. Even if you feel tired, caffeine creates a chemistry in your brain that makes it difficult to fall asleep. Caffeine suppresses our sleep hormone, melatonin, and instead promotes the production of our stress hormone, adrenaline; the exact opposite of what we need to sleep well. The last thing we need if we want to give our body a chance to recharge its battery is for the brain to be chemically affected. This can create a vicious cycle where we need the caffeine to keep us going, while at the same time the caffeine shortens and disrupts our sleep and the deficit increases.

Small doses are best

A typical cup of coffee contains around 100-150 mg of caffeine. It takes an average of 5-7 hours for the amount to be halved. If we consume a regular cup of coffee containing 120 mg of caffeine, it will take 5-7 hours for half of the caffeine to leave our bloodstream. The remaining 60 mg will still be floating around in your bloodstream, and after another 5-7 hours you will be down to 30 mg. Anything over 150 mg of caffeine in the blood (a good cup of coffee) when we go to sleep has the potential to disrupt our sleep.

But should we stop drink coffee then? Absolutely no. But pay attention to the amount of coffee you consume and the timing. This is what's important to keep in mind if we want to avoid caffeine interfering with our sleep. Drink your cup of coffee in the morning and supplement with water in the afternoon.