why do we sleep?

reasons why we sleep

We sleep because of Hunger and Eating

“While we may not often think about why we sleep, most of us acknowledge at some level that sleep makes us feel better. We feel more alert, more energetic, happier, and better able to function following a good night of sleep. However, the fact that sleep makes us feel better and that going without sleep makes us feel worse only begins to explain why sleep might be necessary.

One way to think about the function of sleep is to compare it to another of our life-sustaining activities: eating. Hunger is a protective mechanism that has evolved to ensure that we consume the nutrients our bodies require to grow, repair tissues, and function properly. And although it is relatively easy to grasp the role that eating serves— given that it involves physically consuming the substances our bodies need—eating and sleeping are not as different as they might seem.

Both eating and sleeping are regulated by powerful internal drives. Going without food produces the uncomfortable sensation of hunger, while going without sleep makes us feel overwhelmingly sleepy. And just as eating relieves hunger and ensures that we obtain the nutrients we need, sleeping relieves sleepiness and ensures that we obtain the sleep we need. Still, the question remains: Why do we need sleep at all? Is there a single primary function of sleep, or does sleep serve many functions?”


In my own words, when we sleep we are growing, and our brain is repairing our tissues because of what we ate that day. Eating and sleeping are more alike than we think. Going without eating makes us very hungry, and going without sleep makes us unbelievably tired("Hunger and Eating").

my commentary

I think this website should have gave better and more understanding information. I like how this article compared eating and sleeping together. It told me how they are alike and how they are different.

We sleep to Learn

“Sleep may help the human brain get better organized - by filing away important memories and discarding unwanted information.

"That, if then I had waked after a long sleep, will make me sleep again; and then, in dreaming, the clouds me thought would open and show riches ready to drop upon me; that, when I waked I cried to dream again"

~ William Shakespeare

In a study by Turner et al, 40 people were allowed only 26 minutes sleep per night. They were given cognitive tests which showed their working memory deteriorated by 38% over four days. Without REM sleep, they found it much harder to complete memory tasks and solve problems.

Other sleep experiments have shown that procedural memory (your ability to perform certain skills) is dependent on REM sleep. Similarly, declarative memory (your knowledge of facts) relies on getting enough Slow Wave Sleep.”


In my own words, sleep helps us to organize our thoughts and memories. All the facts and problems we had that day need to be organized so the morning we wake up we will remember everything that happened the day before. Also while we sleep, our brain gets rid of information that we don't need("Why do we sleep anyway?")

my commentary

I think that it was very surprising that our brain gets rid of information that we don't need. I think it is cool how when we sleep our brain organizes all of our memories and thoughts. This is a very good article with good facts.

Work Cited

"Why Do We Sleep? Modern Theories of Sleep." Why Do We Sleep? Modern Theories of Sleep. N.p., n.d. Web. 19 May 2015.

"Why Do We Sleep, Anyway?" Why Do We Sleep, Anyway? N.p., n.d. Web. 19 May 2015.