Lacking Sweet Dreams These Days? Culprit May Be the iPad In Your Bed

Is there a chance you're reading the news in the dark -- in your bed?

Can't put down the tablet, or laptop, or cell phone?

If so, you're probably not alone.

According to consumer research, millions of Americans bring their cellphones, tablets and e-readers to bed every night. The trend is causing concern in the medical community based on increasing evidence that the light emitted by the devices is contributing to sleep loss.

Last month, the American Medical Association issued a policy recognizing "that exposure to excessive light at night, including extended use of various electronic media, can disrupt sleep or exacerbate sleep disorders, especially in children and adolescents."

According to researchers quoted in the Chicago Tribune, any light at night can be disruptive, but in recent years, studies have zeroed in on the particularly potent "blue light" emitted abundantly from the energy-efficient screens of smartphones and computers.

Translation: Sleeping with your iPad may not be helping you sleep.

From the Chicago Tribune's story:

Because blue light is especially prominent in daylight, our bodies associate it with daytime, which may be why exposure to blue light can make us more alert and improve our response times. It also has been shown to suppress melatonin, a hormone that helps regulate sleep and is not produced during the day.

In May 2011, Swiss researchers at the University of Basel reported that subjects who spent time at night in front of an LED computer screen, as opposed to a screen emitting a variety of colors but little blue light, experienced "a significant suppression of the evening rise in endogenous melatonin and sleepiness."

But couldn't the same be said about TV, which is a longtime late-night past time for those who can't sleep?

Apparently not. Unlke TV, which also emits blue light, electronic devices such as phones and iPads are positioned closer to our faces, thus increasing the intensity and effects of the blue light on our brains.

"Blue light preferentially alerts the brain, suppresses the melatonin and shifts your body clock all at the same time," Harvard Medical School sleep researcher Steven Lockley was quoted as saying. "Your brain is more alert now and thinks it's daytime because we have evolved to only see bright light during the day."