Not sleeping well? Turn off your cell phone
A new study suggests that cell-phone radiation could be causing sleepless nights.

By Anne Fisher
Last Updated: August 25, 2008: 10:51 AM EDT


(Fortune Small Business) -- Your phone may be keeping you awake - and not because it's ringing.

According to a research study earlier this year which got little attention on this side of the Atlantic, mobile phones send out radiation that hampers people's ability to sink into the deep stages of sleep. Scientists from Karolinska Institute and Uppsala University in Sweden, and from Wayne State University in Michigan, gathered 35 men and 36 women between the ages of 18 and 45 and exposed about half of them to 884-megaherz wireless signals identical to those emitted by cell phones. The other half got no radiation. The result: The people who had been subjected to the radiation took longer to enter the deep stage of sleep that refreshes and restores, and spent less time there, than the other group.

The study was funded by a trade association called the Mobile Manufacturers Forum, which represents the biggest cell phone companies in Europe. After the findings were published by MIT, the embarrassed cell phone makers tried to play down the experiment's results, saying they were "inconclusive."

But Bengt Arnetz, the Swedish professor who led the study, says there is no doubt that cell phones "have measurable effects on the brain." He believes that the radiation from phones activates the brain's stress system, making people feel more alert and decreasing their ability to wind down and snooze.

"And bear in mind, when you're talking on the phone, there is a mental stimulus from the conversation itself, in addition to the radiation," Arnetz says. "The combination makes it doubly hard to relax into deep sleep."

Other European research backs him up. One landmark study followed 1,656 Belgian teenagers for an entire year and found that most of them talked on their cell phones in bed at night before falling asleep. The kids who did so just once a week were more than three times as likely as non-phone users to describe themselves as "very tired" during the day, while the teens who talked in bed on more than one night a week were five times as likely to report tiredness.

What about Wi-Fi computer signals? Can they interfere with sleep? The scientific jury is still out, but consider this: Kevin Koym, who owns a consulting company and a software engineering firm in Austin, Tex., says of his struggles with insomnia: "I never had sleep problems until I started using Wi-Fi So now I am careful to shut off my computer at home in the evening."

Whatever the scientific verdict, taking a nightly break from your electronics can't hurt. So turn off the computer, power down the CrackBerry, and relax.