As smartphones become an increasingly present part of everyday life, a new study warns they could be having a detrimental effect on teenagers' sleep.
Researchers from the University of Basel in Switzerland analysed the smartphone usage and sleeping patterns of more than 300 students, finding that individuals who spend more time online are more likely to experience problems drifting off at night.
Doctors found that teenagers with smartphones spent double the amount of time (two hours in total) on the internet each day in comparison to their counterparts with more basic mobile phones, while also sending significantly more texts - an average of 85 per day compared to just seven.
What's more, only 17 per cent of those with smartphones turned them off when they went to bed, in contrast to 47 per cent of teenagers with basic mobiles. This may have encouraged smartphone users to carry on using the internet, therefore distracting themselves from getting a good night's sleep.
Results of the study showed that young people who went online or sent text messages at night were more likely to report poor sleep, as well as symptoms related to depression, potentially affecting their mood during the day.
The publication of this research comes as the National Sleep Foundation in the US has announced new recommendations for the amount of sleep individuals should try to get each night.
For 14 to 17-year-olds, this comes in at between eight and ten hours, while for those aged 18 to 25, it is seven to nine hours.
Charles A Czeisler, chairman of the board of the National Sleep Foundation and professor of sleep medicine at Harvard Medical School, explained: 'This is the first time that any professional organisation has developed age-specific recommended sleep durations based on a rigorous, systematic review of the world's scientific literature relating sleep duration to health, performance and safety.'
Furthermore, doctors recommend that phones and the internet are switched off at least one hour before an individual goes to bed to encourage a better night's sleep.