Over-use of the internet is causing mental health problems for children, government health advisers have warned. Each hour spent in front of a computer puts them at greater risk, they say. As a result, children face mental illnesses and social problems such as loneliness, depression, anxiety, low self-esteem and heightened aggression. In a report submitted to MPs, Public Health England officials warn that one in ten children now has a mental health issue, with computers and the internet largely to blame. Public Health England, which issues guidance on good health to the NHS, says there is a clear relationship between the amount of time spent on social media sites such as Facebook and ‘lower levels of well-being’. The link becomes particularly striking when children spend more than four hours a day in front of a screen – but it kicks in even at very low levels of use.