Data is still emerging on this relatively new topic, but research so far seems to indicate that the health benefits of reading can be negated in digital books.

For example, reading a book has long been associated with one of the routines that leads to better quality sleep. However, a study out last year found that reading from a tablet or iPad before bedtime may actually disrupt sleep quality.

Researchers at the Brigham & Women's Hospital in Boston followed every nightly twitch, turn and snore of 12 volunteers over a two-week period. They found that those who read from a screen had a harder time falling asleep, spent less time in the crucial "REM" (Rapid Eye Movement) phase of sleep, and were less alert the next day.

They concluded that back-lit devices are especially powerful when it comes to suppressing the release of melatonin, the hormone that brings on sleep.

Reading from such a device "is exactly what you don’t want to do at bedtime," says Charles Czeisler, the study’s senior author. "Many people read things to help them fall asleep. They probably don’t realize that this technology is actually making them less likely to feel sleepy."

Another study from Norway's Stavanger University last year found that readers absorb less information on Kindles than on paper. In the survey, 50 readers were given the same short story to read. Half read the 28-page story on a Kindle, and half in a paperback, with readers then tested on aspects of the story including objects, characters and settings.

Researchers found that those who used a Kindle "performed significantly worse on the plot reconstruction measure, i.e., when they were asked to place 14 events in the correct order."

"When you read on paper you can sense with your fingers a pile of pages on the left growing, and shrinking on the right," says lead researcher Anne Mangen. "You have the tactile sense of progress, in addition to the visual ... [The differences for Kindle readers] might have something to do with the fact that the fixity of a text on paper, and this very gradual unfolding of paper as you progress through a story, is some kind of sensory offload, supporting the visual sense of progress when you're reading."

It's early days but this could suggest that the impact of reading on enhancing memory is less potent in eBooks, compared to actual books.

Book smart; the unexpected health benefits of being an avid reader