How to Get a Good Night's Sleep

Over half of American adults regularly have trouble falling asleep. Millions more are presumably tired enough to go to sleep, but choose to stay up for a variety of reasons (work, family, Three Stooges reruns). Between those who can't fall asleep and those who willfully decide they have better things to do, America is a land of zombies during waking hours. Sleep researchers confirm the ideal amount of sleep is what your mother always told you: about eight hours per night.

According to a National Sleep Foundation survey, the average American is short an hour of sleep, getting just six hours and 54 minutes per night. And it's getting worse: One-third of respondents said they got less sleep than they did five years ago. It is now the norm in many professions to regularly put in 12- to 18- hour days and get fewer than five hours of sleep per night. Ask a first-year investment banker at Morgan Stanley.

Sleep deficits catch up with you eventually. One out of five Americans reported feeling so sleepy during the day that it interfered with their activities. Exhaustion can be dangerous too. Sleep researchers have found that staying awake for 18 hours is equivalent to 0.08 blood alcohol content (the legal driving limit in many states). And those young physicians working 36-hour shifts? You don't want to know.

During sleep, your brain's nerve cells recharge themselves, according to the latest theory by the National Institute on Aging. If you regularly stay up into the wee small hours of the morning, consider that the latest research partially attributes obesity, diabetes, infections, and colds to a lack of sleep. Getting up in years is no excuse either: Researchers believe older people need just as much sleep as everybody else-eight hours.

Sleep consists of four stages: light sleep, true sleep, deep sleep, and rapid-eye movement (REM) sleep. One round-trip through the four stages takes from 90 minutes to two hours. A full night's sleep consists of four complete cycles. If your sleep is interrupted after stage two you will feel tired the next day. For this reason, naps should either be less than 45 minutes or a full two hours, to avoid disrupting the deep and REM sleep stages.

If you get eight hours but still seem fatigued, you may have sleep apnea. Some 14 percent of adults have the syndrome, which involves the cessation of breathing for a few seconds during sleep, and is caused by the tongue or other tissue blocking the throat. Intense log-sawing interrupted by spooky quiet is sleep apnea's signature. You can identify it readily: Ask your spouse. If you (or your spouse) just can't take it any more, a nasal mask worn to bed can give relief.

Dropping a few pounds might help too; overweight people, especially males, are likely candidates for sleep apnea. Extreme cases may require surgery. See a sleep disorders clinic for your options.