It’s bad habit to use a smartphone or tablet to surf the internet or read an e-book at bedtime.
That’s because it’s harder to fall asleep when your eyes are exposed to the blue light emitted by the device. It also leads to a poorer quality of sleep and makes you feel tired the next morning.
These are the findings of a team from Harvard Medical School, who compared the impact of reading before sleeping on those who read paper books and those who read from electronic devices.
The two-week experiment involved 12 volunteers, who spent five days reading a paperback and five days reading from an iPad.
Regular blood samples showed reading an e-book slowed their production of the sleep hormone melatonin, BBC reports. As a result, they took longer to fall asleep, had less deep sleep and felt more tired the next morning.
To be sure, their findings are not new, but the experiment serves to support the contention of many experts that exposure to light before bedtime affects our sleeping pattern.
As we all know, we have a body clock that tells us the time of day, when to sleep and when to wake up.
The blue light coming from electronic devices can disrupt this body clock, slowing or preventing the production of the hormone melatonin that we need to have a deep and rejuvenating sleep.
“The light emitted by most e-readers is shining directly into the eyes of the reader, whereas from a printed book or the original Kindle, the reader is only exposed to reflected light from the pages of the book,” Prof. Charles Czeisler, the lead researcher, told BBC News.
And lack of sleep is bad for the health.
“Sleep deficiency has been shown to increase the risk of cardiovascular disease, metabolic diseases like obesity and diabetes, and cancer,” he said.
Their study was published in the journal Proceedings of the National Academy of Sciences.
– Contact us at [email protected]