TEENAGERS who stay up at night glued to social media sites such as Facebook, Instagram and Twitter are more likely to feel anxiety and depression, according to Scottish researchers.

The pressure to keep in touch with their internet peers 24-hours a day is leading young people to ignore the need for sleep, bringing a risk of developing harmful personality disorders.

Scientists at Glasgow University measured the sleep quality and social media use of 467 teenagers and found that pressure to be available online and respond to messages impacted on their mental health.

They have warned that parents should ensure their young ones learn to switch off from the digital world and get some rest away from computer screens, tablets and phones.

It comes on the back of further recent research claiming Scotland has become a "smartphone society" with new research showing that the handheld machines are the most popular route to getting online.

According to research by the communications watchdog Ofcom, nearly four in ten (37 per cent) of internet users north of the Border cite the handsets as the most important device for accessing the internet, compared to 26 per cent for laptops.

Analysis showed that overall and night-time specific social media use, along with emotional investment in social media, were related to poorer sleep quality, lower self-esteem as well as higher anxiety and depression levels.

Led by Dr Heather Cleland Woods of the University of Glasgow, the study suggested parents should ensure children turn off their devices at night .

The study is being presented at the British Psychological Society conference in Manchester.

Lead researcher Dr Cleland Woods said “While overall social media use impacts on sleep quality, those who log on at night appear to be particularly affected.

"This may be mostly true of individuals who are highly emotionally invested. This means we have to think about how our kids use social media, in relation to time for switching off.”

She added that increased use of social media added to the turmoil felt by those going through adolescence, and that more work was needed to fully determine the effect on teenagers wellbeing.

She said: “Adolescence can be a period of increased vulnerability for the onset of depression and anxiety, and poor sleep quality may contribute to this. It is important that we understand how social media use relates to these.

"Evidence is increasingly supporting a link between social media use and wellbeing, particularly during adolescence, but the causes of this are unclear."

The Ofcom research found that in 2013 and 2014 the most used social media platforms in the UK were Facebook, Twitter and WhatsApp.

Twitter used declined, from 28per cent to 26per cent of those polled, with Facebook rising to 97per cent, and Instagram rose from 12per cent to 16per cent.

Tablets are also seeing an increased use in Scotland.

Half of adults in Scotland (52per cent) said they had one in the household, a 10 percentage-point increase since 2014 (42per cent).

Six in ten adults (63 per cent) in Scotland own a smartphone, compared to the UK average of 66per cent.

Broadband take up on Glasgow is still behind the UK figure of 80per cent, at 75per cent, but 75per cent of the city now accesses the internet through iPhones, tablets, and smartphones, while 62per cent of the city has fixed broadband in their households.