There’s nothing like ending the day with a good book to help your mind unwind and send you restfully to the land of nod. But what if your preferred reading is now on an iPad or a Kindle Fire? Rather worryingly for millions of lovers of e-books, a group of eminent scientists in the States now postulate that, far from inducing sleep, back-lit e-readers are actually keeping people awake.

The scientists say that the problem lies in the blue glow emitted by back-lit e-readers which inhibits the production of melatonin – one of the building blocks of our daily rhythms. Without melatonin, we do not feel sleepy, and our body clock falls out of synch with the earth’s rotation.

The study, conducted by Penn and Harvard Universities, focussed on 12 participants who read electronic books for four hours before bed over a two week period. They then repeated the experiment for two weeks reading traditional books. Researchers found reduced levels of melatonin during the e-book cycle, with readers taking on average 10 minutes longer to fall asleep.

According to researcher Dr Anne-Marie Chang, lit screens can have an “extremely powerful effect” on our circadian rhythms and disrupt our sleep patterns. Lead researcher Prof Charles Czeisler goes on to say that there is a “special concern” for teenagers who have a delayed body clock and therefore already struggle with getting up for school.

It would appear that there’s nothing quite like a real book or an original Kindle reader, illuminated with a built-for-purpose reading light, to keep your body at one with nature at night time.

Sources:

1. BBC - E-Books:
   E-Books 'damage sleep and health,' doctors warn.