Is the light late at night from your tablet too bright? Professor Shantha Rajaratnam, a researcher from Australia, thinks so.  According to Rajaratnam, nighttime use of portable digital devices could lead to increased sleep disorders.

“We think that the advent of electric lighting has significantly impacted upon sleep-wake patterns, but with the proliferation of electronic devices that emit light we are expecting that these problems will increase,” said Rajatnam

A similar study by Dr. Lois Krahn, a psychiatrist at the Mayo Clinic in Scottsdale, Arizona, shows that handheld devices emit around 30 to 50 lux. Rajaratnam explains, “We know from preliminary reports that this level of light emission, 30 to 50 lux, is sufficient over a week or so to delay the timing of the circadian clock as well as suppress the production of the hormone melatonin.” And without melatonin, a hormone that helps to regulate sleep, snoozing becomes a whole lot more difficult.

Based on the study at the Mayo Clinic, Dr. Krahn makes two recommendations. Use middle or low settings for brightness and keep the device at least 14 inches from your face.

Of course, you could always just turn the device off …