Want a good night’s sleep? Read a book


There are many ways to slide into a good night’s sleep -- here, we’re concerned with just one of them: reading. And if you take to bed with a good book on your tablet, like the man above, you’re doing it wrong.

That’s according to a new study -- a teeny, tiny study -- at Rensselaer Polytechnic Institute’s Lighting Research Center. RPI found that looking at a backlit screen, like those on iPads and other tablets, can lead to sleeplessness.

“Our study shows that a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22 percent,” said Mariana Figueiro, the lead researcher. “Stimulating the human circadian system to this level may affect sleep in those using the devices prior to bedtime.”


In the study, 13 subjects read, watched videos and played games on tablets with backlit displays for two hours. The subjects were equipped with devices to measure the light their eyes were receiving, and some wore goggles that filtered the light they saw.

Results of the study, titled “Light level and duration of exposure determine the impact of self-luminous tablets on melatonin suppression,” were recently published in the journal “Applied Ergonomics.” It was funded by Sharp Laboratories of America.

Another researcher suggests that teenagers and young adults, who “tend to be night owls,” may be particularly sensitive to the tablet light exposure.

What’s a bedtime reader to do? These results suggest avoiding backlit tablets and reaching for something else. A text-only Kindle, for example. And paper books, while old fashioned, work perfectly.

Happy reading, and happy sleeping.

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