School day starts too early, teen health experts say

A body of research is emerging to lend support to something every teenager is probably aware of – school starts too early!

In the United States, this growing consensus is causing educators and policy makers to consider a shift away from traditional early school start times.

Boasting high profile supporters including Education Secretary, Arne Duncan, the movement for starting school later in the day  is based on multiple studies highlighting the physical and mental benefits of pushing back the first-period bell.

Teens need more sleep than adults

According to Dr. Gail Gross, Ph.D., it’s time to banish the image of the lazy, morning-shy teenager. Whereas adults need, on average 7 to 8 hours of sleep, the biological changes which happen during the years of adolescence mean that teens need 8.5 to 9.5 hours sleep each night for their growing bodies.

In addition, teenagers experience a chronotype shift that creates a late-to-bed, late-to-rise schedule.  This means the teenage brain secretes melatonin, aka the ‘sleepy hormone’, from approximately 11pm until 8am, markedly later than the majority of adults.

So it’s no wonder with classes beginning at 7:15am, many students spend the first part of the school day in a sleepy stupor.  And because they must rise early to attend school on time, teenagers are not receiving an adequate amount of sleep each night, which accumulates in a “sleep debt” that can contribute to a number of health problems.

Sleep deprivation and the teenage brain

Some of the health hazards of sleep deprivation, according to Dr. Gross and mentioned in The School Start Time Study, include:

  • loss of the ability to focus and stay on task
  • symptoms of fatigue, mental lapses, and ADHD
  • more rash and emotional decision-making
  • increased the risk of depression or difficulty relating to peers or parents
  • greater likelihood of using alcohol and other drugs

In his article, The Science of Sleepy Teenagers, neuroscientist Russell Foster adds to this list, asserting that sleep deprivation disrupts hormonal balances in teenagers that can predispose people to chronic health problems like diabetes, obesity, and hypertension.

To make matters worse, teenagers compensate for their sleep debt by consuming more sugary or caffeinated drinks.  Not only can these choices contribute to problems like obesity, but they can make it more difficult to fall asleep at night.

Dr. Foster also comments that tiredness can increase the likelihood of a person taking up smoking.

Studying later school start times

Three major studies have helped ignite the movement towards later school start times.  In 1996, a research team at the Center for Applied Research and Educational Improvement led by Kyla Wahlstrom conducted the first longitudinal study of later high school start times.

The study evaluated two Minneapolis-area school districts that shifted their start times to 8:30am or later.  In 2010, Dr. Judith A. Owens led a similar study on the impact of a 25-min delay in school start time.

In 2014, Dr. Julie Boergers worked together with Dr. Owens to publish a subsequent study of a boarding school in Rhode Island that delayed class start times by 25 minutes.  The three studies found similar benefits for students from the modest delays in start times.

The perks of being perky

With as little as a 25 minute delay in school start times, the research highlighted numerous advantages for teenagers, the list of benefits including:

  • increased overall sleep time, with the percentage of students sleeping eight or more hours per night more than doubling
  • significant reductions in daytime sleepiness
  • improvements in mood and focus.
  • lower student caffeine intake
  • significant reductions in school dropout rates and depression
  • higher grades

These studies also suggested that improved sleeping habits from delayed start times could benefit teenagers by:

  • better restoring the brain and metabolism through sleep
  • enhancing memory, learning, and emotional balance
  • preventing erratic behavior, truancy, absenteeism, obesity, and even car accidents
  • providing students improved impulse control, sociability, and alertness 

These findings have even inspired Time Magazine to suggest that offering standardized tests like the SAT later in the day would increase average scores by 15 points.

Gaining momentum

Although some have expressed concerns about the potential impact later school start times could have on logistical issues such as transport and family schedules, according to Dr. Wahlstrom, there is no cause for alarm;

“…initially Edina parents were concerned about the effect of later starts on such logistical issues as busing, athletics, and child care for younger students. But at the end of the first year of implementation, 92 percent of respondents on a survey for Edina high school parents indicated that they preferred the later start times.”

More and more schools all over the country are beginning to implement later start times based on these studies, hoping to duplicate the successful results in their own students.

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Disclosure: Ms. Uno has no relevant financial or nonfinancial relationships to disclose.

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