Reading a tablet will stuff up your sleep -

A scientific study has just discovered a link between reading using a backlit computer screen and a lack of sleep.

The study comes from the Lighting Research Centre (LRC) at Rensselaer Polytechnic Institute and shows that a two-hour exposure to backlit displays causes melatonin suppression.

It has has a dramatic impact on teens, so letting them read from a tablet will probably keep them awake at night and sleepy during the day. The researchers did not explain how they could tell the difference between a melatonin deprived teen and a healthy one.

According to the journal Applied Ergonomics, which we get for the back breaking crossword, Mariana Figueiro, associate professor at Rensselaer and director of the LRC's Light and Health Program, gave 13 individuals self-luminous tablets to read, play games, and watch movies on.

She said that the study shows that a two-hour exposure to light from self-luminous electronic displays can suppress melatonin by about 22 percent.

Causing it to drop to this level is enough to affect sleep in those using the devices prior to bedtime.

This study could urge manufacturers to design more "circadian-friendly" electronic devices. In fact they could be tuned to wake you up in the morning and make you a bit snoozy before going to bed.

Melatonin is a hormone produced by the pineal gland at night. Researchers found that exposure to light at night, especially short-wavelength light, can slow or even cease nocturnal melatonin production.

Apparently if you want to watch your tablet and have a snooze afterwards the secret is to wear orange tinted glasses. So Ian Paisley should be asleep most of the time.