Whether you know it or not, current U.S. federal guidelines mandate that every high school student get practically nine hours of sleep per night. A new study from Brigham Young University found that students ages 16 to 18 will perform better academically if they get two hours less rest per day than the government’s recommendation. The study’s author, Eric? Eide said, “We’re not talking about sleep deprivation. The data from the study clearly show that seven hours of sleep is optimal at this age.” The new study, conducted by Eide and his colleague Mark Shah, professor of economics at Brigham Young University, is the first in a series of studies designed to examine sleep and its impact on our health and education. Surprisingly, the current federal guidelines are based on studies that simply tell teenagers to keep sleeping until they are satisfied. ”If you used the same approach to develop guidelines for how much people should eat, you would put them in a pantry with plenty of food prepared and just observe how much eating would satisfy them,” Shah said. “That just doesn’t seem right.” In this new study, researchers at Brigham Young University sought to reveal the link between sleep and performance or output. Data for the study came from a representative sample of 1,724 students in elementary and middle schools from across the United States. They found a strong relationship between how much sleep adolescents got and how well they performed on standardized tests. But more sleep isn’t always better, and as they report in the Eastern Economic Journal, appropriate sleep duration decreases with age: optimal sleep duration for age 10 is 9 – 9.5 hours optimal sleep duration for age 12 is 8 – 8.5 hours optimal sleep duration for age 16 is 7 hours “We don’t just start with ‘your child may be sleeping too much’ perspective,” says Eide, “on the other hand, if a child is only getting 5.5 hours of sleep a night because he has too much on his schedule, he will do better with an extra 90 minutes of sleep a night .” The size of the impact on test scores depends on a variety of factors, but reducing a child’s sleep by 80 minutes per night is equivalent to parents giving their children more than a year of schooling. ”Most of our students at Brigham Young University, especially those who take morning classes in high school, will recognize that the best students don’t get nine hours of sleep a night,” Shah said.