Web of sleeplessness

You hit the sack after a long day, but instead of sleeping, you check your Instagram, Twitter, Facebook and e-mails one last time. Two hours later, you're still up reading, tweeting and replying to e-mails.

If you're one of those people who sleep with their mobile devices or tablets next to their pillow (as 90% of 18- to 29-year-olds are doing, according to a study by OnlinePsychologyDegree.net), you may be woken up by notifications throughout the night.

More and more research says we're not getting enough shut-eye , and our gadgets are to blame.

According to a study by Rensselaer Polytechnic Institute's Lighting Research Centre, exposure to the backlit display in most gadgets (such as smartphones, TVs and tablets) for two hours before bedtime can interrupt sleep. This is because the displays suppress melatonin, a hormone used in the human sleep-wake cycle, by 22%.

Researcher Brittany Wood said in the study: "To produce white light, these electronic devices must emit light at short wavelengths, which makes them potential sources for suppressing or delaying the onset of melatonin in the evening, reducing sleep duration and disrupting sleep."

With a study revealing that one in three people would rather give up sex than their phones, and that one in four people are woken in the middle of the night a few times a week by mobile devices, technology is not only coming to bed with us, but it's keeping us awake too.

The OnlinePsychology study reveals that one in two people will automatically check their phones when they wake up in the middle of the night.

I do this too. Initially it is to check the time, but I find myself checking e-mails, Instagram and Twitter. Sound familiar? I'm sure it does, particularly to the social media-obsessed younger generation.

But using our gadgets late at night isn't just bad for your sleep - it's bad for your psychological health too. Research by John Hopkins University published in the health journal Nature revealed that our use of gadgets can result in depression and anxiety.

The university's Samer Hattar told Medical News Today: "Chronic exposure to bright light - even the kind of light you experience in your own living room at home or in the workplace at night if you are a shift worker - elevates levels of a certain stress hormone in the body, which results in depression and lowers cognitive function."

RPI researchers recommend we dim electronic devices when using them at night to minimise melatonin suppression and limit the use of devices prior to bedtime.

Many people claim they cannot fall asleep without the assistance of reading (sometimes on their tablets or e-readers such as Kindles), watching television or surfing the internet, but if these devices are having adverse effects on our sleep, it's time to consider falling asleep the good old fashioned way: by counting sheep.