Why Do We Sleep?

Sleep is one of the most wonderful gifts that has been bestowed on us by Mother Nature. After a tiring day at work, nothing is more rewarding than a good, peaceful slumber. All you need is a comfy bed, a pillow or two, the right temperature and Zzzzz…


Sleeping Baby Meme



Everyone sleeps, right? Think as long and as hard as you want, but it’s highly unlikely that you’ll ever find a person who doesn’t sleep at all. It’s true that not all people sleep in the same way; in other words, not everyone experiences the same sleep quality. Some people become totally oblivious to the world around them when they sleep, while others are light sleepers who wake up at even the softest of sounds. However, even if it’s just a short nap, everyone catches some sleep nearly every day.

So. if everyone does it, then there must be a reason behind it. Let’s tackle the notion of sleep from an inquisitive perspective: Why do we sleep?

We Need It!

Brain At Rest

Credits:Beatriz Gascon J/Shutterstock

Sleep is one the most important aspects of our life, which is evidenced by the fact that we spend almost one-third of our lives asleep! Therefore, if you are a nonagenarian (a person who is between 90 and 99 years of age), then you have slept through roughly 30 years of your life. That’s quite a long slumber!

Although you become unaware of your surroundings when you fall asleep, your brain remains constantly at work (albeit at a slower rate). Certain areas of your brain are activated during sleep; in fact, there are some regions of your brain that are more active during sleep than they are when you’re awake and fully responsive to everything happening around you.

brain during sleep

The reason for sleep is one of those mysteries that has not been fully unraveled, but there are a number of hypotheses that explain why we feel the need to nap!

Process of Restoration

This is the one of the most popular theories behind sleep; we sleep to restore and revive our bodies. Our body enters a mode of restoration while we sleep to restore and rebuild the energy we’ve expended during wakefulness. This hypothesis of restoration, being a rather intuitive explanation, also has evidence to support it. When we’re asleep, there is a whole array of genes that are turned on, and these genes are associated with the process of both restoration and our metabolic pathways.

Information Processing Power

This is actually the most important reason why we might sleep. For many, sleep may just be a ‘thing’ that everyone indulges in once (or multiple times) each day, but in reality, sleep is much more than that. If a person is sleep-deprived for a few days, then they will experience a considerable reduction in their information processing powers. To understand this better, consider a person who has not slept even for a catnap for 4 days straight. If you give the person a set of logical questions to answer, not only will it be very unlikely that they’ll be able to solve the question, but don’t be surprised if you get punched in the face. Sleep deprivation also causes unusually high levels of irritability.

If you’ve taken some wisdom from this article, then do yourself a favor by catching a good night’s sleep. It’s not just something that you do once in a while; it’s a habit that you should engage in throughout your life.


  1. Why Do We Sleep, Anyway? – Healthy Sleep (Harvard University)
  2. Why Do We Sleep? – The Dartmouth Undergraduate Journal of Science
  3. Why Do We Sleep? – California Institute of Technology
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About the Author:

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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