Is Your Cell Phone Keeping You Awake at Night?

You may think that you can’t live without your cell phone. But maybe you’d sleep better without it.

A study from Sweden in 2008 involved 21 healthy subjects between the ages of 14 and 20. They were divided into two groups.

A control group used their cell phones for no more than five calls or text messages per day. The other group used their phones for more than 15 calls or text messages per day. One of these participants had more than 200 text messages per day. Only one of the 21 subjects turned the phone off at night.

Results show that people with excessive cell phone use had a number of sleep problems. They had irregular sleeping hours and took longer to fall asleep.

Their sleep was more agitated, and they woke up more often. It took them longer to reach the stage of deep sleep. They also had more trouble waking up in the morning and were more tired before mid-day.

In 2007 a study in the journal Sleep found that teens who use cell phones after “lights out” are more likely to be tired one year later. The odds of being “very tired” were 3.3 times higher for those who used the cell phone at any time of night.

But it’s not just the time spent on the phone that can hinder your sleep. The cell phone itself – or your exposure to its radio frequency field - may affect your sleep.

One study in 2007 involved 36 women and 35 men. They were exposed to three hours of an 884 MHz wireless signal.

After exposure it took participants longer to reach the stage of deep sleep. They also spent less time in deep sleep.

But another study in 2007 failed to find similar results. Ten subjects were exposed to a defined radiofrequency electromagnetic field. They did not find a significant effect on sleep.

Another study in 2006 exposed 55 volunteers to cell phone emissions for 30 minutes. There was no impact on melatonin production. But there may be an effect on the timing of melatonin production. The body produces more melatonin at night as a "sleep signal."

So it remains unclear how and how much cell phones may affect your sleep. But it may be best to turn your phone off and keep it out of the bedroom at night. Sleep without it, even if you can’t live without it.