Older children to start school later to find out if it suits their biological clocks

Teensleep project seeks to establish if early start is in everyone's interests

Schools across Britain are being asked to take part in a research project to stagger their start times to suit the different biological clocks of children, with ten year olds starting at 9am and 15 year olds starting at 10am.

Scientists believe that the body’s circadian rhythm, which determines sleep-wake patterns over 24 hour periods, varies with a child’s age and that an earlier school start time for all students is not in the best interests of older children.

The research project, funded by the Wellcome Trust, will recruit 100 schools as part of the biggest study yet into the role that school start-times play in the education and wellbeing of students, said Paul Kelley of the University of Oxford.

The natural shift in the biological clock to later in the 24-hour cycle is particularly acute in the 14 to 24 age group. The shift in the biological clock continues in later middle age, when people usually revert to the naturally earlier start time they felt comfortable with when they were 10-year-old children, Dr Kelley said.

“We cannot change our 24-hour rhythms. You cannot learn to get up at a particular time. By the time you are 18, 19 or 20 you are getting up and going to sleep up to two or three hours earlier on average, depending on the time of year later,” Dr Kelley said.

“You are suffering on average two hours of sleep loss a day and is cumulative so that at the end of the week you have suffered 10 hours of sleep loss. It has a hugely damaging impact on the body,” he told the Science Festival in Bradford.

“Students lose more sleep than doctors working a 24 hour shift during every school or university week...Schools are arbitrarily starting at any time they choose. There is no justification and no study suggesting that starting earlier is better,” he said.

“Most people wake up to alarms because they don’t naturally wake up at the time they go to work, so we are a sleep-deprived society and this age group, 14 to 24, is more deprived than any other sector of society,” he added.

The research project, known as Teensleep, will investigate whether there are any benefits in starting school later for the GCSE age group of 14-16 years. Other studies in the US have suggested that students in colleges and universities aged 18 and older can benefit from an even later start time of 11am, he said.

“A number of studies have shown when you move later, things get better. The kinds of changes at this age are quite dramatic - 50 per cent of mental illnesses occur at this age....It may be that part of the problem is a circadian time shift and a sleep-deprivation problem,” Dr Kelley said.

“It is a bit of an ask to go to your school governing body to say that we need to change our times but the mood in the place changes for the better - there are more emotional interactions,” he said.

“This applies to the bigger picture, to employers, to prisons to hospitals where everyone is woken up at 6am to be given food they do not want,” he told the meeting.