E-readers have grown in popularity
With the growth of e-books over the last few years, we have seen an explosion in the variety of e-readers with Amazon alone offering 4 models in the Fire range and 3 in the Kindle range. Alongside those, there are models by Kobo, Sony and Nook. Of course this is not the only way to read ebooks as there are Ipads and other tablets, laptops and pc’s, and a friend of mine even reads on the train using his mobile phone. With the growth in size of mobile screens as we have seen with the introduction of the IPhone Six Plus and the Samsung GalaxyS6, these bigger devices are starting to resemble mini-tablets and reading a book on a phone will become increasingly more widespread.
Of the seven e-reader models offered by Amazon, only 1, the basic Kindle does not utilise backlit technology. It, and some models by Nook and Sony, utilise E-Ink technology, which effectively ‘sprays’ words onto the screen and the unit doesn’t use any battery power all the time the page is visible. The displays of all the other devices mentioned above – tablets, laptops, pc’s and mobile phones, all use some form of backlit technology.
Why is this important?
In day-to-day usage, it doesn’t make much difference how you read your eBook, although many people report their eyes tiring quicker when reading from a screen, rather than from a newspaper or paperback book. It starts to become important when these devices are being used last thing at night. Research has shown that using a backlit device before going to sleep, not only stops you falling asleep quickly, it also reduces the amount of quality REM sleep you have.
A Little Science
When trying to fall asleep, your body generates a hormone called melatonin. Researchers at Harvard University Medical School have shown that the blue wavelength light emitted by backlit devices can slow down or prevent the production of melatonin, causing people who use them late at night to experience trouble in falling asleep and making them feel more tired in the morning.
Is sleep loss important? Lead researcher on the Harvard study, Prof Charles Czeisler, says ‘sleep deficiency has been shown to increase the risk of cardiovascular disease, metabolic diseases like obesity and diabetes, and cancer.’ It is also well documented that a deep, REM sleep is essential for your body to repair damaged cells and for your brain to sort out all the disparate pieces of information collected during the day into their proper places.
What should you do?
To improve your sleep quality, minimise the use of computers, tablets and mobile phones late in the evening. This is particularly true of teenage children who already have a late body clock that keeps them up at night and are difficult to get out of bed in the morning, and the use of laptops and phones before sleep only exacerbates the problem.
If you like to read before falling asleep, choose a paperback, newspaper or a basic Ereader that is not back-lit such as the Kindle, Nook Simple Touch (without the glow light) or the Sony PRS600.