Why does your body need sleep?

Last I read, they still aren't exactly sure. It is said to refresh systems, or is an evolutionary adaption to keep a species from harm when certain predators are about, or to reduce the need for food.

Importance of sleep

Sleep is essential for a person’s health and wellbeing.

	Moonrise -  1189 pts -  (2 years ago)
	...I'm not sure that really answers the question.

I just learned this in Psychology class this week.

Sleep is a mental and physical restoration process. Over time, when people go without sleep, they lose the ability to control their emotions and they become more emotional "fragile". Basically, people tend to lose personal control.

Also, sleeping is very important for mental functioning. During the day we have experiences and at night when we sleep our minds strengthen these experiences and we form memories. Without sleep, we cannot form memories (or at least not strong ones). Without sleep, you shouldn't expect to do well in school.

Another side effect of poor sleep habits is weight gain. I believe this is caused by the stress that occurs when sleep is deferred.

Your brain actually is wearing down as you constantly use it.
You can lay your body to rest and not do anything, but your brain is still generally highly active.


Did you know dolphins have learned to sleep with on half of their brain at a time to allow swimming while sleeping?