A Good Night's Sleep

By Alice Park

Who doesn't welcome the sweet oblivion of a good night's sleep? The sad reality, however, is that a decent slumber is increasingly hard to come by. The average adult sleeps an hour and a half less now compared with more than a century ago, thanks to the Internet, e-mail, cell phones and 24-hour entertainment that all take bites out of the sleep cycle. If you need incentive to put some of those hours back into it, consider this: the amount of sleep you get may endanger your life. That's the conclusion reached by a new study conducted in Britain at University College London Medical School.

Research has long documented that people may pay for shorter slumber with a shorter life span. Sleep is the body's opportunity to rest and repair what the day has wrought, and if your heart is working at its 3 p.m. rate when the clock hits 3 a.m., it's simply going to wear out faster. In the new study, epidemiologist Jane Ferrie questioned 7,700 British civil servants about their sleep habits over an eight-year period and found that those who slept six to eight hours nightly at the beginning of the study but decreased the amount of rest they got by the end of it increased their risk of dying from heart disease 110%. "When you sleep, your blood pressure drops, your heart rate drops, and the heart doesn't have to work as much," explains Dr. Lawrence Epstein, medical director of the Sleep Health Centers in Boston. Makes sense; still, the more than doubling of the risk surprised both Epstein and the authors of the paper.

The natural answer to getting too little sleep is to sleep more--perhaps a lot more. But hold on. Ferrie found that short sleepers who slept each night for five hours or less did indeed decrease their overall risk of dying within eight years when they snagged two to three more hours of sleep a night by the end of the study. But once they started piling up too much sleep, crossing the line to nine hours or more daily, the risk of dying--not from heart disease but from other causes--rises the same 110%. Too few subjects in Ferrie's study fell into this category for her to offer explanations of the findings, but others will undoubtedly investigate how excessive sleep can contribute to health problems. For now, aim for the six-to-eight-hour sweet spot and stay there--without sleeping pills, incidentally, which produce a poorer-quality sleep that's as bad as getting too little. It's a simple solution that may pay off in big ways. [This article contains a chart. Please see hardcopy or pdf.]