E-Books and Sleep Disruption

We've written countless times on the importance of sleep - just click on the topic "sleep" in the searchable index on the right hand side of this post. But now we need to sound a cautionary note about a recommendation that we often make to students -- to use an E-reader, such as a Kindle or an iPad for most of their reading. We recommend these devices for many reasons. They allow students to easily click on the definition of unfamiliar words without needing to put down a book and seek out a dictionary. Many versions allow students to highlight text. They enable students who struggle with reading decoding to easily increase the size of the text they view, something which research has shown makes it easier for some students to decode the words on a page. And they often have audio capacity, which allows students to hear the words pronounced while reading them on the e-Reader page, something that enhances the connection between the written word and the spoken sounds and builds comprehension.

In short, we are big fans of e-Readers and the accessibility and convenience they offer. But a recent study by Harvard Medical School researchers has demonstrated that E-readers, which the study refers to as LE-eBooks (for light emitting electronic books), can have a negative impact on health and sleep when used before bedtime. As noted in an online report in Harvard Medical School News:

“We found the body’s natural circadian rhythms were interrupted by the short-wavelength enriched light, otherwise known as blue light, from these electronic devices,” said Anne-Marie Chang, corresponding author and associate neuroscientist at Brigham and Women’s Division of Sleep and Circadian Disorders. “Participants reading an LE-eBook took longer to fall asleep and had reduced evening sleepiness, reduced melatonin secretion, later timing of their circadian clock and reduced next-morning alertness than when reading a printed book.”

Different e-devices have different levels of brightness and the study used only iPads. Still, they all use blue light in some form and can be expected to have some impact on sleep.

So, what does that mean for parents and students? E-readers still have significant benefits and their use can provide not just convenience for everyone, but real help to those who struggle with reading. But this well-crafted study should prompt families to think about how -- and when -- these devices are used. The bedtime story, whether it is one you read to your child, one your child reads by himself, or your own end-of-day reading time, will be better for all if done from a paper book.