It’s better to let sleeping teens lie
Grainy-eyed and reaching for the coffee? Grumpy and wishing you could hit the snooze button for a few more minutes of sweet sleep? If you are struggling because of a lack of sleep, chances are that your child is having an even harder time of it. New research has found that early school starting times are playing a significant role in children’s moodiness and impairing their ability to function.
"Sleep deprivation is epidemic among adolescents, with potentially serious impacts on mental and physical health," says Dr Julie Boergers, a psychologist and sleep expert at the Bradley Hasbro Children’s Research Centre in the United States.
Her team took a group of about 200 high school students in a boarding school, and adjusted their school start times from 8am to 8.25am.
The average age of the student was 15 years old.
Students slept longer, with the number of those who got eight or more hours of sleep jumping from 18% to 44%.
Also, "daytime sleepiness, depressed mood, and caffeine use were all significantly reduced after the delay in school start time," writes Boergers in the research paper, which was published in the Journal of Developmental and Behavioural Paediatrics.
Once the early start was reinstituted, the students returned to their normal sleep patterns.
The effect on mood and functioning of an adolescent does not surprise Dr Karine Scheuermaier, a sleep expert at the University of the Witwatersrand’s Dial a Bed Sleep Laboratory.
Teenagers need slightly more sleep than adults and sleep at different times, she says.
It hinges on humans’ internal biological clock, known as the circadian rhythm, which dictates when we want to sleep and wake up.
"During teenage development, it’s been shown in several carefully designed laboratory studies that our internal biological clock … shifts to a later time [compared with adults] … Planning to start school early ... leads to adolescents having to wake up too early and therefore not getting enough sleep," Scheuermaier says.
But there are greater concerns than your child being grumpy.
Scheuermaier lists a number of negative side effects: it decreases their ability to consolidate new information, increases their risk of depression and disturbs the regulation of hormones controlling appetite, leading to a higher risk of obesity, metabolic disorders and type 2 diabetes.
Boergers, who is also co-director of the Paediatric Sleep Disorders Clinic at Hasbro Children’s Hospital, says: "The results of this study add to a growing body of research de-monstrating important health benefits of later school starting times for adolescents. If we more closely align school schedules with adolescents’ circadian rhythms and sleep needs, we will have students who are more alert, happier and better prepared to learn, and aren’t dependent on caffeine and energy drinks just to stay awake in class."
Scheuermaier says: "If we want adolescents to get their eight to nine hours of sleep ... this means they should have their wake times around 7am to 8am ... If we want our teenagers to have enough sleep, the best time to start school would be around 8.30am to 9am."
Attempts to get comment from the department of basic education on school times were unsuccessful.