Sleep is something we do throughout our entire lives, from the moment we are born until the moment we are finally laid to rest. In fact, during an average life span, a person spends the equivalent of 27 years asleep!

Sleep is such a natural tendency that most of us don't give it much thought. When we do think about sleep, it's usually because we haven't gotten enough of it or because we feel the need to do it for longer than what would be considered 'normal'.

As taken for granted as sleep is, it really is a controversial topic. There are countless differences of opinion as to why we sleep, how much sleep we should be getting each day, where we sleep, what makes the ideal sleep environment, why we don't sleep enough and why we sleep too much.

The general consensus is that sleep is necessary otherwise we wouldn't spend so much of our lives doing it. Most also agree that sleep is our way of giving our minds and our bodies a rest. While sleep patterns and needs vary from person-to-person, the general consensus has always been that sufficient sleep is an absolute necessity.

Conclusions from the earliest studies about sleep indicated that the body entered a state of near paralysis during which time little activity took place. This belief changed dramatically when studies began focusing on brain activity. The realization that brain activity did not stop during the sleep state but instead was highly active and organized and carried out several physiological processes is what we refer to today as REM or Rapid Eye Movement sleep.

Sleep seems to be the body's way of recharging after a busy day. Some would argue that sleeping is a waste of time and that there are ways to train ourselves to get by with much less sleep.

Most of us can miss one night's sleep and still function rather normally the next day. Doctors do it all the time. There may be an increase in irritability and perhaps some trouble staying focused, but overall, the body and the mind still function.

Beyond that though, there is a noticeable decline in the mind's capabilities, specifically in the areas that control our language, our memories and our ability to plan. The symptoms that can develop are similar to the symptoms that develop after consuming excess amounts of alcohol including slowed reactions and impaired rationalization skills. At this point, an individual faces an increased risk of becoming involved in an accident.

A lack of sleep can cause problems properly regulating body temperature and can cause metabolism to increase. After several days of no sleep, hallucinations usually begin. So it does seem that we need to sleep

Some of the popular theories about why we need sleep are:

Sleep is a restorative process.
Sleep enhances the brain's ability to remember.
Sleep is a way to conserve energy.
Sleep is a way to keep us safe from predators.
Sleep just feels way too good!

The real reason why we need sleep will likely be discovered some day, but until then, the mystery continues. In the meantime, science strives to understand as much as possible about sleep's effects and patterns, as well as our need for it. If you're interested in learning more about sleep and how it affects you, visit for more information.