The American Academy of Pediatrics has a new policy: teens need their sleep. And to log in enough hours at night, this means starting school not earlier than 8:30 in the morning.

Sleep is essential for everyone but the AAP is highlighting the importance of getting enough rest at night for teens, citing improved health and better academic performance as some of the benefits.

A typical teen needs between 8.5 and 9.5 hours of sleep to be fully rested. According to a survey done by Shakira Suglia and colleagues from Columbia University's Mailman School of Public Health on 10,000 young adults and teens, around a fifth of 16-year-olds get less than six hours of sleep at night. The National Sleep Foundation adds that just one out of five adolescents consistently gets nine hours of sleep during school nights.

"As adolescents go up in grade, they're less likely with each passing year to get anything resembling sufficient sleep. By the time they're high school seniors, the NSF data showed they were getting less than seven hours of sleep on average," said Judith Owens, lead author for the AAP policy. Owens is also the director of sleep medicine at the Children's National Medical Center based in Washington, D.C.

Can't teens just sleep earlier to make sure they'll get plenty of rest to get them ready for the next day?

Apparently, that's near impossible for a teen. When one hits puberty, they experience changes in their circadian rhythm or the internal body clock responsible for regulating sleeping and waking patterns. This makes it unlikely for a teen to naturally fall asleep before 11 p.m. Given the required hours of rest, a teen is programmed then to wake up around 8:00 a.m. Since students already have to be in school at that time, teens have to wake up earlier, cutting back on the hours of rest that their bodies require.

Without enough sleep, teens face higher risks of depression, anxiety, decreased motivation, vulnerability to stress, poor school performance that leads to lower academic achievement, car accidents due to drowsiness, and even type 2 diabetes, stroke, and obesity.

Afternoon naps may be able to boost focus and alertness for teens deprived of sleep but these do not offer the same benefits as a good night's rest. Neither does sleeping in during weekends as this also throws off sleeping schedules.

Looks like the AAP's recommendation to start school no earlier than 8:30 a.m. is the most plausible solution at the moment -- even U.S. education secretary Arne Duncan supports it.