Teenagers Need More than Seven Hours Sleep
An academic paper released in 2012 suggested that teenagers may in fact need only just more than seven hours sleep to perform well in standardised tests. The article was not written by sleep researchers but by economics researchers who used statistical analysis to come up with this proposal. However the paediatric sleep community has refuted this suggestion.
In an article on this happychild website called How Much Sleep Does Your Teenager Need? we provided some useful guidelines for parents about helping teenagers get enough sleep each night, and information about the risks of your teen being sleep deprived. The accepted guideline from sleep experts is that your teenager will require about nine hours sleep per night.
The Seven Hours Only Idea
Economics researchers from Brigham Young University studied the relationship between sleep and student performance of 1724 children, aged between 10 and 19 - their research indicated that optimal hours of sleep decline with age. Using student questionnaires and test scores, the researchers found that for optimal results on standardised tests, the amount of sleep needed becomes lower as a child gets older. Their statistical analysis indicated that the “optimal amount of sleep to maximise test score performance” for 16 year olds is between 7.02 and 7.35 hours.
Response from the Paediatric Sleep Community
However, Dr Gradisar, a researcher specialising in child and adolescent sleep problems
at Flinders University in South Australia, kindly alerted us to the response to the Brigham Young University paper by experts who specialise in sleep, and in particular, who specialise in children's sleep.
To give parents the full story on how much sleep teenagers need, we have extracted parts of a letter by Dr Mary Carskadon from the Children's National Medical Center, Alpert Medical School of Brown University, Washington DC and Dr Judith Owens, MD MPH, Director of Sleep, Children's National Medical Center, Washington DC :
"Representing scores of scientists who study sleep's role in the health and welfare of children, we need to be clear: current expert recommendations for the sleep needs of children may not be perfect or immutable, but they are based on sound and rigorous science. For the sake of children whose parents, pediatricians and teachers may have seen recent media reports on two papers that call this into question, we're compelled to offer the context of what decades of research has produced.
... abundant research shows that sleep is a vital component of physical and mental health in children and adolescents. ... Experts acknowledge that there is some individual variability in sleep needs and therefore these recommendations are offered as 'guidelines' for parents. They should be viewed in the context of potential signs of
insufficient sleep in children and teens (difficulty waking in the morning,daytime sleepiness, sleeping longer on weekends and school vacations).
Also, the recommendations for sleep amounts, such as those posted by the National Sleep Foundation (NSF), should always be applied in conjunction with other healthy sleep practices (such as regular bedtimes and wake times and bedtime routines).
... We also need to be clear about the health effects of inadequate sleep, given the outward appearance that sleep cuts into 'productive' time. Many lay people may not know that sleep is enormously productive time - especially for the developing brain - when the brain organizes itself and consolidates the day's learning.
Here are the stakes. A large number of studies have shown associations
between insufficient sleep and adverse health outcomes in teens and younger
children. These include:
- increased obesity risk;
- higher rates of motor vehicle accidents and accidental injuries,
- reduced cardiovascular health, and
- increased risk of depression and suicidal ideation.
Many other studies have demonstrated the negative outcomes of sleep restriction and the positive impact of sleep extension on cognitive function of children and teens.
In a recent paper in the Eastern Economic Journal, two Brigham Young University economists dismiss such serious medical findings when they purport to determine an 'optimal' amount of sleep for kids based on one question ("how many hours of sleep do you usually get a night?") and a small set of standardized test scores. They report that that teens who got less sleep than experts recommend got better scores. We take issue with aspects of their methodology, but even if their paper were technically unassailable, as health professionals we would still be compelled to ask why a narrow set of test scores should be any parent's benchmark for optimal sleep when so many vital health conditions are endangered by too little sleep.
Ultimately, the key issue is to define how much sleep kids and teens need. That's long been a priority of our field because parents and pediatricians have always worried about this question and have needed science to provide answers. What has changed over time has been the increasing quantity and quality of science we've been able to apply. Many rigorous pediatric sleep research studies have done much to help address the issue of optimal sleep duration and healthy sleep practices in children and adolescents. These
studies include large epidemiologic approaches as well as rigorous field tests and in-lab brain wave monitoring. We've posted a selected list of these studies and those referenced above, as well as more co-signers to this essay, on our website.
For all these reasons, we feel we should put in context a recent paper in (the journal)
Pediatrics that gained substantial and unduly credulous media attention.
... A careful look at the paper shows that almost all of their findings are driven by data in infants, for whom recommendations around the turn of the last century were hugely different from those around the turn of this century. Meanwhile, the sleep recommendations at other ages are pretty much on par across the century. Fundamentally by ignoring many strong studies that provide a quantitative basis for current sleep recommendations, the authors do a serious disservice to parents,
pediatricians, educators and, ultimately, to children.
The scientific literature shows that children and adolescents experience better learning and academic success and greater physical and mental health when their sleep is protected and supported to levels recommended by a consensus of experts, such as those posted on the NSF website. Our hope is that by understanding the scientific record and context beyond these two recent splashes in the literature, the pediatric sleep community's service to parents and pediatricians can be restored."
Mary A. Carskadon PhD, Professor, Psychiatry and Human Behavior Medicine, EP Bradley Hospital, Alpert Medical School of Brown University 20010-2970
Judith Owens, MD MPH, Director of Sleep, Children's National Medical Center, Washington DC, Providence, RI 02906