School start times should be put back to as late as 11am to combat a sleep-deprivation crisis among young people, a scientist has suggested.



Paul Kelley, of the Sleep and Circadian Neuroscience Institute at the University of Oxford, said young people in Britain were losing on average 10 hours’ sleep a week, making them more sleep-deprived than a junior doctor on a 24-hour shift.



Speaking at the British Science Festival in Bradford on Tuesday, Prof Kelley called for an end to early starts at schools, colleges and university to “improve the lives of a generation”.



He said children aged eight to 10 should start school at 8.30am or later, 16-year-olds should start at 10am and 18-year-olds at 11am.

Kelley has been working with fellow Oxford neuroscientist Russell Foster and Steven Lockley of Harvard Medical School to push for a sea-change in the approach to sleep for children.

They have been working with the Education Endowment Foundation and the Wellcome Trust on the Teensleep project, which Kelley said was the largest study of its kind and which is aims to recruit 100 schools to trial different start times.



The recommendations arise from a deeper understanding of circadian rhythms – our internal body clock, which determines optimum levels of concentration, wakefulness and work ability.

“At the age of 10 you get up and go to school and it fits in with our nine-to-five lifestyle,” Kelley said. “When you are about 55 you also settle into the same pattern. But in between it changes a huge amount and, depending on your age, you really need to be starting around three hours later, which is entirely natural.”



Ignoring our natural circadian rhythms could lead to exhaustion, frustration, anxiety, weight gain and hyper-tension, he said, and could make a person more prone to stimulant or alcohol use and risk-taking.



“This is a huge issue for society,” Kelley said. “We are generally a sleep-deprived society but the 14-24 age group is more sleep-deprived than any other sector of society. This causes serious threats to health, mood performance and mental health.”



If schools across the UK adopted the new start times, he said, GCSE attainment would rise by about 10%.

The problem goes beyond merely feeling tired, Kelley said. If a child gets less than six hours sleep a night, over the course of a week this can lead to more than 700 changes in the way their genes behave.

Similar changes are not seen in children who get eight-and-a-half hours sleep a night. He said illnesses as serious as schizophrenia often developed at an age associated with the beginnings of sleep deprivation problems.

Kelley said every governing body of every school in the UK had the power to alter start times if they wish. He conceded that later school starts might be problematic for working parents, but added: “The interesting thing is that parents usually support this. All the studies show that later start times improve family life, travel times are shorter, it’s safer for children to travel to school.”

Guy Meadows, a sleep physiologist at the Sleep School in London, agreed there was a problem that needed tackling. He said: “British children are among the most sleep-deprived in the world. There was a recent study which looked at 900,000 children globally. The US was top and Britain came sixth. Sleep is vitally important for children, and it’s when they develop mentally, physically and emotionally.”

He said families had a key role to play in ensuring children get enough sleep. In school sessions aimed at teaching children how to improve their sleep, Meadows said, 96% of participants said they used a phone or mobile device in the last 30 minutes before sleep.

“We’re finding that children have phones or tablet from the age of about 10 or 11. These devices emit light which mimics the light from the sun and they essentially trick our brains into thinking we should be active, not winding down for sleep, and that interferes with our circadian rhythms,” he said.