High school students suffer from early start times, studies reveal

The Science of Sleep

The average teenager needs about nine hours of sleep a night.  But how many teens actually get that much sleep in one night?  According to the National Sleep Foundation, only one in five.  And nearly half of all adolescents sleep less than eight hours on week nights.

The cause of their sleep deprivation?  According to several sleep experts, it’s high school start times.

“The teenager’s clock tends to want to wake up later in the morning, but school starts earlier,” said Dr. Scott Eveloff, who is the medical director of the sleep lab at SomniTech, Inc, a sleep disorder center with locations throughout the midwest. “Teenage internal clocks tend to run delayed, which can become a big problem if it interferes with getting to school on time.”

Despite the late hours of teenagers’ body clocks, many high schools across the country have early start times, with the first bell ringing at 7, sometimes even 6 a.m.

“As children reach adolescence, their circadian rhythms–or internal clocks–tend to shift, causing teens to naturally feel more alert later at night and wake up later in the morning,”  according to the National Sleep Foundation’s Sleep in America Poll, conducted in 2006.  “This natural shift in teens’ internal clocks is often at odds with classroom clocks.”

Early Bird Gets the Bad Grade

More than one half of adolescents go to bed at 11 p.m. or later on school nights, and wake up around 6:30 a.m. for school, leaving many with an inadequate night of sleep according to the National Sleep Foundation.  Over the course of a week, high school seniors miss 11.7 hours of neeeded sleep.  Adequate sleep is extremely important says Dr. Eveloff, but few realize it.

“Lack of sleep can lead to poor daytime function, poor school performance, reduced memory and focus,” Eveloff said.

According to Dr. Travis Schlenger, a polysomnographic technologist (a doctor who studies sleep disorders), many students also have what’s called EDS, or excessive daytime sleepiness.

“[Sleep deprivation causes] EDS, [which is the] inability to concentrate,” Schlenger said.  “It hinders your ability to retain information, and it is harder to concentrate and stay on task.

According to the poll by the National Sleep Foundation, at least once a week, more than a fourth of high school students fall asleep in school, and 14% arrive late or miss school because they oversleep.  However, among those few students who do get enough sleep on the week nights, 80% of them say they’re achieving As and Bs in school, while students who get insufficient amounts of sleep tend to have lower grades, according to the poll’s findings.

Furthermore, sleep deprived teens are more likely to get into car accidents, because their focus is reduced.

“Lack of sleep can [also lead to] reduced reaction time while driving,” Dr. Eveloff said.

According to the National Highway Traffic Safety Administration, young people, specifically people 18 to 20 years of age, were involved in five times more fatigue-related accidents than any other age group, due to irregular sleeping habits.  However, in a Kansas county, car crashes decreased 16.5 percent among 17 and 18 year olds after schools in the county changed their start times to an hour later, even while the rest of the state had a 7.8 percent increase in car accidents.

Sleeping In

Research nationwide shows that students benefit from later school start times, and these benefits can be seen from their school work to their attendance to their mood.  In the Minneapolis, Minn. school district, the start time changed in 1996 from 7:20 a.m. to 8:40 a.m., which affected 12,000 high schoolers.  According to education researcher Kyla Wahlstrom from the University of Minnesota, who conducted the five-year long study, many students claimed they were in better moods, and teachers and parents also saw a significant difference in their students.

“Students reported less depression when there was a later starting time,” Wahlstrom said. “And teachers reported that students were more alert and ready for learning. Parents reported that their children were easier to live with because their emotions were more regulated.”

In addition, Wahlstrom found in the study that the later start times also caused an increase in attendance and a decrease in drop out rates among students.

According to Dr. Eveloff, most students would benefit from a later starting time, but the delayed high school day may conflict with the teachers’ and parents’ day.

“I actually think performance could be improved with a later start time, given what we know about the standard teen’s sleep physiology,” Eveloff said.  “However, teachers, administrators, and parents are all running on adult physiology, so there will be conflict. The rest of the world does not adjust start time because employees would like to sleep in.”