Teens who go to school late may perform better –researcher

Teens who often complain about getting out of bed on a school day might be onto something after all.

 

Russell Foster, a professor of circadian neuroscience, there is now a growing acceptance that the academic day should consider adolescent sleep patterns and start at a later hour.

 

"The biology of human sleep timing, like that of other mammals, changes as we age. This has been shown in many studies. As puberty begins, bedtimes and waking times get later. This trend continues until 19.5 years in women and 21 in men," Foster, who chairs the Nuffield Laboratory of Ophthalmology and is a director of the Sleep and Circadian Neuroscience Institute of the University of Oxford, said in an article on NewScientist.com.

 

"(F)or a teenager, a 7 a.m. alarm call is the equivalent of a 5 a.m. start for a person in their 50s.," he added.

 

Foster pointed out that while the amount of sleep teenagers get varies in geographic region and social class, all studies show they tend to go to bed later and may not get as much sleep they need because of early school hours. Real-world examples

 

He noted the UCL Academy in London is the latest school to adopt a later start time due to teens' sleep patterns, even as others "are considering following suit."

 

In the US, Foster noted teenagers' biologically delayed sleep patterns prompted several schools to put back the start of the school day.

 

He said this could enhance attendance and academic performance, along with less sleeping in class and self-reported depression.

 

In the UK, for example, Monkseaton High School near Newcastle instituted a 10 a.m. start in 2009 and saw an improvement in academic performance.

 

"However, a later start by itself is not enough. Society in general, and teenagers in particular, must start to take sleep seriously," he said.

 

"Sleep is not a luxury or an indulgence but a fundamental biological need, enhancing creativity, productivity, mood and the ability to interact with others," he added.

 

Foster said the sleeping trend reverses as people age, with those aged 55 likely to wake up "at about the time we woke prior to puberty," he said.

 

But for teens, he said it would be wise to adjust schedules to their body clocks.

 

"It is my strongly held view, based upon the evidence, that the efforts of dedicated teachers and the money spent on school facilities will have a greater impact and education will be more rewarding when, collectively, teenagers, parents, teachers and school governors start to take sleep seriously. In the universal language of school reports: we must do better," he said.

 

Biology, other factors

 

Foster said biology is not the only reason for this phenomenon.

 

He said additional factors include a more relaxed attitude to bedtimes by parents, a general disregard for the importance of sleep, and access to TVs, DVDs, PCs, gaming devices, and cell phones.

 

"(A)ll of (these) promote alertness and eat into time available for sleep," he said.

 

9 hours' sleep

 

NewScientist.com quoted Mary Carskadon at Brown University in Providence, Rhode Island, said teenagers need about nine hours a night to maintain full alertness and academic performance.

 

Foster added his own recent observations at a UK school in Liverpool suggested many were getting just five hours of sleep on a school night.

 

"Unsurprisingly, teachers reported students dozing in class," he said.

 

He added sleep is important for memory consolidation and the ability to "generate innovative solutions to complex problems."

 

In contrast, he said sleep disruption increases the level of the stress hormone cortisol.

 

As a result, "impulsive behaviors, lack of empathy, sense of humour and mood are similarly affected," he said.

 

"All in all, a tired adolescent is a grumpy, moody, insensitive, angry and stressed one," he said.

Metabolic changes  

But even more critical is that the loss of sleep is associated with metabolic changes.

 

"Research has shown that blood-glucose regulation was greatly impaired in young men who slept only 4 hours on six consecutive nights, with their insulin levels comparable to the early stages of diabetes," he said.

 

Also, studies showed lack of sleep triggers higher levels of the hormone ghrelin, which promotes hunger, and lower levels of leptin, which creates a sense of feeling full.

 

He noted adolescents increasingly use stimulants - usually caffeinated and/or sugary drinks - to cope with sleep loss.

 

Tiredness also increases the likelihood of taking up smoking, he added.

 

"The suggestion is that long-term sleep deprivation might be an important factor in predisposing people to conditions such as diabetes, obesity and hypertension," he said.

 

"Collectively, a day of caffeine and nicotine consumption, the biological tendency for delayed sleep and the increased alertness promoted by computer or cellphone use generates what Carskadon calls a 'perfect storm' for delayed sleep in teenagers," he added.

 

'Take control'

 

Foster suggested that teens also "take control" in their sleep:

 

"Ensure the bedroom is a place that promotes sleep – dark and not too warm – don't text, use a computer or watch TV for at least half an hour before trying to sleep and avoid bright lights. Try not to nap during the day, and seek out natural light in the morning to adjust the body clock and sleep patterns to an earlier time. Avoid caffeinated drinks after lunch," he said. — TJD, GMA News