How Caffeine Affects Sleep: Main Questions and Answers

Since you’ve just opened this article, I bet you’ve drunk at least a cup of coffee today. Or maybe more. Anyway, you are not the only one who regularly uses caffeine to stay awake. Coffee and other caffeinated beverages are a very important part of our daily diet.

Sociologists from Gallup say that some two-thirds of adult American population drink at least one cup of coffee every day. The average amount of coffee consumed per day reaches 2.7 cups, and more that 25% Americans admit that they are addicted to coffee. In other countries of the Western world, the situation is roughly the same.

Not only people use coffee as a tasty drink, but it is perhaps the easiest and the most popular way to maintain energy and stay up all day (and also night). On the other hand, various negative effects of caffeine for sleep and for health in general are a matter of common fears. In this article, we will deal with the most popular questions and myths about caffeine’s effects on people’s sleep and will tell how to drink coffee and sleep healthy.

What Caffeine Is

Caffeine is a psychoactive drug, which is widely used as a natural stimulant. Of course, it has medical and other functions, but enhancing performance is the main goal caffeine is applied for. In the article, we will explore how it disrupts sleep and helps keep energy.

Since coffee is the most popular way of taking caffeine, I will refer mostly to this drink in this article. Yet, lesser amounts of caffeine can be found in tea, cola, energetic drinks, and other beverages. The caffeine amount is one standard cup of coffee is roughly equal to its amount in 2.5 bottles of cola or 0.5 bottles of “energy shot” drink.

The Influence of Caffeine on Our Sleep in 5 Questions

  1. How does caffeine disrupt sleep?

Short answer: If consumed a few hours before sleep, caffeine disrupts the ability to fall asleep and worsens the quality of sleep.

Detailed answer: Everyone knows that caffeine helps maintain energy and avoid falling asleep, and it’s the major reason why we drink coffee. How does caffeine achieve that? Basically, it just blocks the action of adenosine receptors, which have sedative effects for our body, and replaces them with itself, as well as stimulates our autonomic nervous system. The scientists have long been noticing the direct influence of caffeine on sleep, which is reflected in “increased capability for arousal and decreased the ability to develop or sustain deeper stages of non-rapid eye”. Put in normal English, caffeine helps us wake up and prevents the stage of deep sleep.

So, when you drink coffee a few hours before sleep, it will be more difficult for you to fall asleep quickly and sleep well. These negative effects can appear even if you take caffeine 6 hours before going to bed. The recent study, which was conducted by scholars from Michigan, analyzes the effects of drinking coffee 0, 3, and 6 hours before sleep, and comes to the conclusion that even the last option can significantly reduce total sleep time. So, if you want to sleep long and well, you should avoid consuming caffeinated drinks prior to your bedtime.

  1. So, can I just drink a lot of coffee and sleep 4 hours per night?

Short answer: Not if you care about your health at least a bit. You still need to get enough sleep, and coffee will not be able to help avoid that.

Detailed answer: The ability to sleep less and staying fresh is very desirable in the modern society, and there are ways to achieve it. But just drinking more coffee and relying on it will be not only not helpful but even harmful for your health. There are two reasons why simply increasing the amount of caffeine you take won’t do you any good. First, caffeine’s “boost” can just disappear if you don’t get enough sleep. Second, excessive use of caffeine has a lot of negative effects on our body.

The first point can be proven with the recent study done by the Academy of Sleep Medicine. Scientists explored the influence of caffeine on sleep when a person extremely lacks sleep. What is the influence of coffee in such situations? Well, this influence simply doesn’t exist. After three nights of sleeping 5 hours per night, coffee will no longer improve your performance. So, if you want coffee to work for you, try to get a decent amount of sleep at least sometimes. And, of course, don’t forget about negative effects, which caffeine can cause for your sleep. We will talk about them in the next question.

  1. What negative effects of caffeine you are talking about?

Short answer: When you take too much caffeine, you can face long-term troubles with the health of your sleep, such as sleep disturbance or insomnia.

Detailed answer: “Enough is as good as a feast”, our grandfathers (or their grandfathers) used to say. Moderate coffee drinking can improve your performance and be useful for your health, but when you take it too much, it is bad for your health in general and especially for your sleep. What negative effect does caffeine cause for sleep? The first one is sleep disturbance. When you are addicted to coffee too much, you can experience long-term sleep disorders, such as mild sleep disruption, which decreases the length and quality of your sleep.

Other two major effects of being too much into caffeine are insomnia and polyuria. Insomnia is also known as sleeplessness, and this term speaks for itself. People who take too much caffeine, always face difficulties sleeping, such as being unable to fall asleep or being sleepy during the daytime. Then you drink a cup of coffee to be less sleepy, and this vicious circle never ends. The second effect, named with the Greek-originated word polyuria, is simply excessive urination, including nocturia, which is the need to urinate throughout the night. So, if you don’t want to experience those, remember about moderation.

  1. So, is caffeine so harmful to my health and sleep? Should I stop consuming it at all?

Short answer: No, the previous question doesn’t mean that you must not take caffeine at all. No more that 4-5 cups of coffee per day might be useful for your performance and beneficial for the health.

Detailed answer: Of course, drinking too much coffee and other caffeinated beverages is bad for your health, but it’s not a reason to avoid caffeine completely. In moderate amounts, caffeine is positive for improving performance, helps enhance productivity, and improve memory and concentration. So, coffee can really make you work more effectively. Just consume it wisely.

What amount of caffeine should you take? According to the Food and Drug Administration of the United States, an ordinary healthy adult may consume 400 milligrams of caffeine a day. When measured in brewed coffee, it’s 4-5 standard cups of coffee. Of course, if you do drink 5 coffee per day, it’s much recommended not to take “energy shot” drinks or other beverages with a high level of caffeine. People with health problems and pregnant women should limit the amount of caffeine more radically. For children under 12, it’s better not to take caffeine at all.

  1. How do I need to consume caffeine to sleep well and stay healthy?

Short answer: Limit the amount of caffeine you take and don’t drink coffee in the second part of the day. Combine coffee with afternoon naps.

Detailed answer: Let’s start with two major tips which should have already been obvious from everything we’ve said above. First of all, you will need to limit the amount of caffeine. As we’ve already discussed, its excessive use doesn’t do any good for your health and for the quality of your sleep. Second, try not to drink coffee before sleep — even 6 hours before sleep.

Another tip for combining caffeine and sleep is combining caffeine and afternoon nap. A proper 20-30 minute daily sleep itself is a good way to sleep less and stay energetic throughout the day because it can dramatically help you keep energy and increase performance. You can achieve great results if you drink a cup of coffee before an afternoon nap. When you wake up in a few minutes, caffeine will start working and will help you stay fresh. Anyway, try to get as much as you can from coffee, but still avoid risking your health.