RISING use of social media is having an adverse effect on the health of young people, say researchers from a Scottish university, and the challenges need to be addressed now.

Dr Jo Inchley, from the University of St Andrews, is the lead author of a report for the World Health Organisation (WHO) that says the dramatic rise in the use of computers and social media is wreaking havoc on young people’s health.

Data for Scotland, England and Wales show that children as young as 11 are spending increasing amounts of time on tablets, computers and smartphones and, as a result, the vast majority of youngsters are failing to take the recommended daily level of exercise. Her study found a “continuous steep increase” between 2002 and 2014 in the proportion of children and young people using technology for two hours or more each weekday, for non-gaming activities such as using social media, surfing the internet and doing homework.

While use increased for both sexes, it more than tripled for girls aged 15 and over during this period, with the rise of social media blamed.

In 2014, for children between 11 and 15 in Scotland, 79.9 per cent of girls and 83.6 per cent of boys used a device for two or more hours on a weekday that was not for playing games. In England the figures were 74.6 per cent and 76.5 per cent respectively, and in Wales 76.4 per cent and 84.6 per cent – all more than a 50 per cent rise on 2002 figures.

Of 42 countries studied by the WHO, Scotland came top for computer use by girls, while Wales was fourth and England seventh. For boys, Wales was second, Scotland third and England 15th.

The WHO, together with experts from the Health Behaviour in School-age Children study, sent questionnaires to more than 200,000 children in schools in 42 countries, including 5,932 in Scotland 5,154 in Wales and 5,335 in England. A breakdown by age showed children as young as 11 spending a large chunk of time online.

In Wales, 53 per cent of boys and 47 per cent of girls aged 11 used a computer for two or more hours for non-gaming activities. In Scotland, the figure was 42 per cent of boys and 45 per cent of girls, while in England it was 39 per cent of boys and 43 per cent of girls. Of 42 countries, Wales ranked third, Scotland fourth and England seventh.

When it came to using computers, tablets or smartphones just for games, between a third and two-thirds of children were spending two or more hours every weekday on them.

Inchley said: “We know that a positive impact of social media is social connectedness and the sense of interaction. But we also know there are risks, such as cyber bullying and impact on mental health, as well as things like missing out on sleep.”

She said there were also impacts on physical health “from being sedentary”, including cardiovascular disease, obesity and Type 2 diabetes.

“One of the main challenges for us is that this kind of activity (social media and computer use) is so much part of young people’s lives these days, how do we manage this and the health risks associated with it?” said Inchley. “It’s about reducing time being spent sedentary, and ensuring that children still have opportunity to be active. We really need to start addressing these challenges now.”

Tam Fry, chairman of the National Obesity Forum, said gadgets were taking their toll on the well-being of youngsters: “Adolescents are now slaves to handheld devices and this is doing nothing for their health.”

Inchley added: “We need to find ways to make young people more active. Maybe they are getting lifts in the car, or are not out playing in the streets any more in the way they used to.”