September 14, 2018
6 min read

Early school start times have detrimental effects on US teens’ health

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Nearly half of American teenagers report sleep difficulties that affect their daily functioning, according to findings published in the Journal of Adolescence. Exhaustion from lack of sleep can lead to negative health outcomes, including depression, obesity and accidental injury.

Compounding these difficulties is a natural shift that occurs in adolescents’ circadian rhythms, which is highlighted by later sleep and wake times. Additionally, teenagers experience a slowing of the homeostatic drive to sleep. A policy statement issued by the AAP also cited the modern teenager’s competing interests — including homework, extracurricular activities, after-school jobs and technology use — that contribute to their lack of sleep on weekdays, requiring catch-up sleep time on weekends. However, sleeping in on weekends can make circadian rhythm changes more drastic.

If teenagers need between a minimum of 8 to 10 hours of sleep per night, and the appropriate bedtime for this age group is 11 p.m., how appropriate are current school start times? Nathaniel F. Watson, MD, professor of neurology at the University of Washington School of Medicine and co-director of the University of Washington Sleep Center, believes that the standard early start time for schools may set adolescents up for sleep problems like insomnia.

“Teenagers have a phase delay in their circadian rhythm that makes it very difficult for them to fall asleep before 11 p.m.,” Watson told Infectious Diseases in Children. “If school bell times are between 7 and 8 a.m., the math does not add up and they are not going to get the sleep they need.”

The AAP policy statement recommended an appropriate wake time of 8 a.m. for those in middle and high school. This prompted both the AAP and the American Academy of Sleep Medicine (AASM) to endorse an 8:30 a.m. or later start time for schools in the United States. The AASM said in their own policy statement that following the new recommendations for sleep duration can improve attention, behavior, learning, memory, emotional regulation, overall quality of life and physical and mental health outcomes. However, a study conducted by the CDC found that in 2014, 82.8% of middle schools and 92.7% of U.S. high schools began before the 8:30 a.m. recommendation.

Study results published in Accident Analysis & Prevention demonstrated that a 75-minute delay in school start times from 7:30 a.m. to 8:45 a.m. decreased the number of adolescents involved in motor vehicle crashes by 14%. Judith A. Owens, MD, MPH, director of sleep medicine at Boston Children’s Hospital, said that teenagers’ sleep deprivation affects the rate of accidental injury and suicide — two of the leading causes of mortality in this population.


Although there are challenges to delaying school start times, including societal norms, Watson and Owens said these can be overcome with education on the subject.

Judith A. Owens

“I frequently encounter parents who believe their child only needs 7 hours of sleep or believe that because they only get 6 hours of sleep, their child should be OK with that amount of sleep,” Owens said. “One of the biggest problems is that humans are terrible at judging how sleepy we are and how impaired that sleepiness makes us. Particularly, when someone has been sleepy at a chronic level, they get used to this low level of functioning and do not really know much better. However, a lot of the adolescents I talk to are well aware of how exhausted they are and feel that it is a huge burden.”

‘A huge logistical issue’

The three specific barriers that interfere with adequate adolescent sleep on school days, according to Watson and Owens, are under the purview of the school district: the status quo, the cost and hassle of bus scheduling, and athletic activities.

“[Sports] tend to be the real limiting factor in many communities because if school starts later, gets out later and the kids get on busses later, their ability to participate in games is different than other schools that they may be competing with,” Owens said. “This becomes a huge logistical issue. While I think this is understandable, it is basically a red herring. There are many communities that have figured out ways to dismiss student athletes early or make traveling to games more efficient.”

Watson suggested that shorter, more efficient practices may be useful for student athletes who acquire the recommended amount of sleep.

“We know that when students are well-rested, they will get much more out of athletic practices than they would if they were sleep-deprived,” he said.

Nathaniel F. Watson

Owens mentioned that one strategy that some communities have adopted is persuading all districts in a league to change school start times. Although this would solve the issue of having a more cohesive athletic schedule among competitors, many school districts are hesitant to change school start times because they believe this is the way schools have always functioned and changing it could impact parents’ work schedules and traffic flow in the community.

Furthermore, delaying school start times may require school districts to purchase more busses and hire more bus drivers to accommodate the changes in the tiered bussing system currently employed in most U.S. school districts. This approach uses the same vehicles to provide service to high schoolers earliest and elementary school students latest, with middle schoolers boarding in between.


Pediatricians’ role

Pediatricians can be a crucial player in efforts to change the way school districts function, according to Watson and Owens.

“It takes a community of concerned parents, students, pediatricians and sleep specialists to go to school board meetings and make sure that this issue is on the docket,” Watson stressed. “These people can speak to [the negative effects of early school start times] and put pressure on the school boards. What I have seen is that, eventually, the school board understands the importance of this topic and makes the necessary changes on behalf of the children.”

Owens said that advocacy for later school start times should begin with an understanding of the benefits and consequences of start times.

“I think pediatricians are generally well-respected in their communities and can educate themselves about this issue to be strong, vocal advocates for their patients,” she said. “The conversation has really shifted from being about academic performance to a matter of health. When something like this, which we can change, has this much of an impact on the health of our patients, it is really our responsibility to work with and educate communities.”

If efforts to change school start times are not supported by the community and school boards, or if the effort to change them has not begun, Watson said teenagers and families are put in a difficult situation. However, small changes in the household can be beneficial to teenagers’ quality of sleep.

“If teenagers have a fixed wake-up time in order to be at school, the only thing you are left with is trying to find ways to get them to bed earlier,” he said. “Having consistent bedtimes on weekdays and weekends, black-out shades and white noise machines help facilitate sleep in teens when they are trying to sleep a little earlier than their homeostatic drive is telling them to.”

Owens also recommended that pediatricians and physicians working with teenagers speak with their patients about the use of screens. The blue light that is found in the screens of televisions, cell phones, computers and other devices can suppress the body’s release of melatonin in the evening, and it makes it more difficult to fall asleep. She suggested turning off all screens at least 30 minutes before bedtime and not allowing teenagers to bring cell phones to bed. She also suggested questioning patients about their sleep hygiene.

“Pediatricians are very good about asking questions about sleep in infancy and in toddlers,” Owens said. “As kids get older, those questions tend to stop. I think it is very important for pediatricians to question their adolescent patients about how much sleep they get and what time they go to bed, whether they sleep in on weekends and if they are sleepy during the day.”

Middle and high schoolers in Seattle, where Watson practices, have had their school start times adjusted to meet the AAP and AASM recommendations. For this to happen in areas where school begins earlier than 8:30 a.m., Watson said that success lies in the strength of the community.

“When communities are successful at implementing these changes, everyone comes together and brings forth a coherent message,” Watson said. “A lot of stakeholders need to show up to school board meetings, present the issue and the AASM and AAP position statements to put pressure on the school board to elect people who see this as the problem that it is. School districts need people who are going to vote for the kids and not for bus schedules.” – by Katherine Bortz

Disclosures: Owens and Watson report no relevant financial disclosures.