I’m not sleeping well, so this article piqued my interest:

A good night’s sleep now appears to be every bit as important to good health and long life as a nutritious diet and regular exercise.

"Sleep is in the top three," says Dinges. "And I think it’s No. 1. Sleep is a biological imperative and not getting enough has health-related costs."

In April, the Institute of Medicine issued a report confirming links between sleep deprivation and an increased risk of hypertension, diabetes, obesity, depression, heart attack and stroke.

Some scientists are exploring possible connections between inadequate sleep and a decline in immune function.

The Archives of Internal Medicine devoted its Sept. 18 issue to the relationship between sleep and health. An editorial called for assessment of sleep habits as a standard part of all medical checkups.

That’s because short sleep can hasten the arrival of the inevitable long sleep. The largest study of sleep duration and mortality was published in February 2002 in the Archives of General Psychiatry. The Cancer Prevention Study II of the American Cancer Society followed more than a million participants for six years. The best survival was found among those who slept about seven hours a night, the worst among those who slept less than 4.5 hours. Too much sleep — nine hours or more — also was associated with a higher risk of mortality.

***

Americans are racking up sleep debt like a college kid with a credit card. About 40% of Americans say they get fewer than seven hours of sleep on weekdays, and most — 71% — get fewer than eight hours of sleep, according to a 2005 survey by the National Sleep Foundation. Even on weekends, they sleep about 7.4 hours — better, but not enough to pay back the week’s loss. Every hour they fall behind is considered an hour of sleep debt, and Americans accumulate about two full weeks of personal sleep debt a year.

Sleep researchers have a name for the way the vast majority of people in this country sleep: volitional chronic sleep deprivation, and it is a lifestyle disorder.

Without enough sleep, the cost in reduced memory, focus, concentration and reaction time is well established. Incidents in the lore of sleep research include the Exxon Valdez oil spill and the Chernobyl nuclear power plant disaster. In each, key decisions were made by people who were sleep deprived.