See how social media could harm your health.

Very frequent use of social media by teenagers can impact their health in complex ways, researchers report.For a new study, scientists analysed data from three sets of interviews with teenagers from nearly 1,000 schools across England, as they progressed from Year 9 (13 to 14 year olds)

in 2013 to Year 11 (15 to 16 year olds) in 2015.The researchers claimed that social media sites are unlikely to have direct effects on brain development, but can harm teenagers in other ways, especially in relation to harmful content such as bullying, and the impact it can have on healthy activities, like sleep and exercise.

 "Our results suggest that social media itself doesn't cause harm, but that frequent use may disrupt activities that have a positive impact on mental health such as sleeping and exercising,

while increasing exposure of young people to harmful content, particularly the negative experience of cyber-bullying," said Professor Russell Viner from the UCL Great Ormond Street Institute of Child Health.

As part of the research, participants reported the frequency with which they accessed or checked social media,

and "very frequent" use was defined as using social networks, instant messaging or photo-sharing services such as Facebook, Instagram, Twitter, Snapchat and WhatsApp multiple - three or more - times daily. In both sexes, very frequent social media use was associated with greater psychological distress, and in girls,

the more often they accessed or checked social media,and "very frequent" use was defined as using social networks, instant messaging or photo-sharing services such as Facebook, Instagram, Twitter, Snapchat and WhatsApp multiple -

three or more - times daily. In both sexes, very frequent social media use was associated with greater psychological distress,

and in girls, the more often they accessed or checked social media, the greater their psychological distress. In 2014, 28 per cent of girls who very frequently used social media reported psychological distress on the general health questionnaire, compared with 20 per cent of those using it weekly or less. However,

this effect was not as obvious in boys. "The clear sex differences we discovered could simply be attributed to girls accessing social media more frequently than boys, or to the fact that girls had higher levels of anxiety to begin with,"

added co-author Dr. Dasha Nicholls from Imperial College London. "Cyberbullying may be more prevalent among girls,

or it may be more closely associated with stress in girls than in boys. However, as other reports have also found clear sex differences, the results of our study make it all the more important to undertake further detailed studies of the mechanisms of social media effects by gender." Full results have been published in The Lancet Child & Adolescent Health.