A lack of sleep among teenagers who are spending the night hours on social media can cause depression and anxiety, according to a study.
Scientists measured the sleep quality and social media use of 467 teenagers and found that pressure to be available online 24 hours a day and respond to messages impacted on mental health issues.
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 "switch off" at night.
The study is being presented at the British Psychological Society conference in Manchester.
Dr Cleland Woods 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.
"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."
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