Why Do We Need to Sleep?
The Latest Fascinating Theories on This Mystery Phenomenon
by SixWise.com

With all of our advances in medicine and technology, with millions of dollars invested in numerous research studies, science still has not been able to definitively understand the purposes behind the natural, inevitable act of sleep.

The exact reasons for why we do it, and why we do it for so long, remain a mystery. Most of what we do know about it comes from understanding it backward: though we don't know why we sleep, we do know that when we don't sleep, our health will soon suffer.

Sleep Helps to Restore Your Body

Like refueling a car or taking a drink of water, it's thought that sleep refreshes your body and helps to restore the energy that you've used up during the day. Says Dr. Neil B. Kavey, director of the Sleep Disorders Center at Columbia-Presbyterian Medical Center in New York City, sleep is the time when your body is able to do repair work. Additionally, when we sleep:

• Muscle tissue is rebuilt and restored

• Growth hormone is secreted (this is important for kids but also for rebuilding tissue in adults)

• Mental energy is restored

And because sleep is your body's time to repair, not getting enough of it can impair your immune system and leave you less able to fight off diseases. This is a major concern, especially when you consider that 75 percent of Americans who responded to the National Sleep Foundation's 2005 Sleep in America poll say they experience symptoms of sleep problems including difficulty falling asleep, waking during the night, experiencing fatigue during waking hours or snoring.

If you belong to this 75 percent, you may want to consider, along with reading the six sleep tips at the end of this article, the Sleep Easy CD. With guided sleep meditations by a leading meditation expert (and contributing editor to SixWise.com) and music by a renowned meditation music composer with 20 years experience, this CD will help you find deep rest and sleep in just minutes every night.

The Brain Never Sleeps

It was once thought that being awake was the natural state of the brain, and that during sleep the brain would take a rest and "shut down," so to speak. But now it's known that, according to the Harvard Medical School, the brain is always in an active state whether the body is sleeping or awake (specific groups of brain structures control the body's functions at different times).

We Need Sleep to Survive

One thing that no one is debating is that sleep is an absolute necessity, but there even have been studies done to prove it. According to the National Institutes of Health (NIH), while rats normally live for two to three years, those deprived of all sleep only live about three weeks, and those deprived of REM sleep (the stage of sleep when we dream and during which it's thought brain regions used in learning are stimulated) survive only about five weeks on average.

At the same time, the rats developed abnormally low body temperatures and sores on their tails and paws. Researchers believe the sores indicate a sluggish immune system and suggest just how detrimental sleep deprivation can be to the immune system of humans.

Sleep and Sickness

Ever notice how when you're sick you're almost always tired? As it turns out, while fighting off infections our immune systems produce powerful chemicals called cytokines that make us sleepy. It's thought that this is the body's way of helping us to fall asleep, during which the body is able to conserve energy and other resources that the immune system needs to fight the infection.

How Much Sleep Do We Need?

It's generally recommended that adults get between seven and nine hours of sleep a night. The NIH gives these additional recommendations:

• Infants generally require about 16 hours a day.

• Teenagers need about nine hours on average.

• Some people may need as few as five hours or as many as 10 hours of sleep each night.

• Women may need several more hours of sleep than usual during the first three months of pregnancy.

• If you've been sleep deprived for several days, you will create a "sleep debt" that will need to be repaid, meaning that you'll need to sleep longer than usual just to function normally and feel rested.

Trouble Falling Asleep?

A past Sixwise.com article, Stress Keeping You Awake? Stressed Because You Can't Sleep?, offers these six tips to help you sleep like a baby tonight.

1. Create a relaxing bedtime routine.

2. Keep your bedroom cool, quiet, and dark.

3. Drink a cup of relaxing tea, like chamomile.

4. Massage your feet.

5. Stretch a bit before you lie down.

6. Once you are in bed, listen to relaxing music or a relaxation or sleep CD to help you "shift gears" and relax into sleep.

While it's not known precisely why you need it, it is known - by your own body most of all - that you do. In fact, adequate and routine sleep is one of the most essential steps you can take to improve your health.

Recommended Reading

How to Relax (and Lower Your Cortisol Levels): A Golden Key to Your Health

Stress Now Proven to Cause Weight Gain in Women: Five Key Stress-Reduction Tips

Stress Keeping You Awake? Stressed Because You Can't Sleep?

Sources

National Institute of Neurological Disorders and Stroke

The Mysteries of Time and Sleep

WFMY News April 1, 2005

MSNBC News