Sleep experts say children need extra hour in bed

British sleep experts have warned that school-aged children are suffering sleep deprivation and are urging education authorities to alter school hours.

The call for change comes after Jean-Michel Blanquer, the education minister in France, last week approved a proposal by the Paris regional council to start classes at 9 am for pupils aged 15 to 18, instead of 8 am before.

A shortage of sleep might cause poor educational results, anxiety and obesity, British experts say, adding that adequate sleep is the most important factor for teenagers' wellbeing and mental health.

Neil Stanley, author of How To Sleep Well, suggests that authorities should move school start times to allow children and teenagers to sleep longer and enable them to better align their biological rhythms, The Guardian reported.

This follows a study published in December in Seattle, which found a "significant improvement in the sleep duration of students" after the start of the school day was delayed by almost an hour in 2016.

In Seattle, the students gained 34 minutes of sleep a day on average and ended up earning higher marks and being absent less.

Teenagers sleep in because their changing hormones tell them to rise later and stay awake in the evening, US experts say.

Michael Farquhar, a consultant in paediatric sleep medicine at the Evelina children's hospital in London, explained that humans' circadian rhythms change in adolescence. The body clock that manages the cycle of sleep and wakefulness shifts two hours later in teenagers.

"It's like they're in a different time zone," Farquhar said, "We're asking them to get up before their body clock is ready, because that's the way the adult world works. So most teenagers end up sleep-deprived."

Last year, British teachers were offered lessons that focused on giving children strategies for getting to sleep and raising awareness about how sleep needs change in adolescence.

Schoolchildren across Britain may be offered sleep lessons to help tackle the problem of insomnia among young people, The Guardian reported last week.

A paper published in the British Medical Journal suggested that sleep has a greater impact on an adolescent's mental wellbeing than bullying, physical activity and screen time.