Co-author, Eric Eide, said:
"We're not talking about sleep deprivation. The data simply says that seven hours is optimal at that age."
Eric Eide and economics professor Mark Showalter set out to determine what impact sleep duration and quality might have on people's education and health. This study report is the first in a series.
The authors say that their findings clash with federal guidelines, which tell teenagers to sleep as long as they feel they need to.
"If you used that same approach for a guideline on how much people should eat, you would put them in a well-stocked pantry and just watch how much they ate until they felt satisfied. Somehow that doesn't seem right."
The researchers wanted to see whether they could associate sleep to a productivity or performance measure. They gathered data on 1,724 primary and secondary pupils across the USA. They added that theirs was a nationally representative sample of schoolchildren.
They found that how much students slept had an impact on standardized academic tests.
However, as far as sleep is concerned, more does not necessarily mean better.
How much sleep schoolchildren require drops with age:
- 10-year olds. The optimal amount is 9-9.5 hours each night
- 12-year-olds. The optimal amount is 8-8.5 hours each night
- 16-year-olds. The optimal amount is 7 hours each night
7 hours sleep per night is the ideal for 16-18 year olds, the study found
"We don't look at it just from a 'your kid might be sleeping too much' perspective. From the other end, if a kid is only getting 5.5 hours of sleep a night because he's overscheduled, he would perform better if he got 90 minutes more each night."
Test performance results depend on several factors, the authors added. However, they did find that an 80-minute adjustment in the direction of the optimum amount seems to be equivalent to a pupil's parents completing approximately one more year of school.
"Most of our students at BYU, especially those that took early-morning seminary classes in high school, are going to realize that 9 hours of sleep isn't what the top students do."