The lack of a clear answer to this challenging question does not mean that this research has been a waste of time. Yet, despite decades of research and many discoveries about other aspects of sleep, the question of why we sleep has been difficult to answer. In other studies, they have looked at sleep patterns in a variety of organisms to see if similarities or differences among species might reveal something about sleep's functions. They have examined, for example, what happens when humans or other animals are deprived of sleep. Scientists have explored the question of why we sleep from many different angles. 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? An Unanswerable Question? 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. Going without food produces the uncomfortable sensation of hunger, while going without sleep makes us feel overwhelmingly sleepy. 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.īoth eating and sleeping are regulated by powerful internal drives. 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. One way to think about the function of sleep is to compare it to another of our life-sustaining activities: eating. 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. We feel more alert, more energetic, happier, and better able to function following a good night of sleep. While we may not often think about why we sleep, most of us acknowledge at some level that sleep makes us feel better.

As with eating well, good sleep is a staple of optimal health.

Sleep no more explanation