By Brian W. Donnelly, M.D.Pediatric Alliance, North Hills Division




“Early to bed and early to rise

Makes a man healthy, wealthy, and wise.”


So quoth Benjamin Franklin.  OK, that was a few centuries ago, before Thomas Edison’s (and Steve Jobs’) influence on our day-to-day lives.  But the venerable Pennsylvanian’s little ditty was based in reality.  We now know that sleep deprivation can adversely affect health and physical performance, not to mention its negative effect on inter-personal relationships.

A nationwide movement to begin the high school day later in the morning is gaining momentum.  A new study from the University of Minnesota indicates why that is:

The results from this three-year research study, conducted with over 9,000 students in eight public high schools in three states, reveal that high schools that start at 8:30 AM or later allow for more than 60% of students to obtain at least eight hours of sleep per school night. Teens getting less than eight hours of sleep reported significantly higher depression symptoms, greater use of caffeine, and are at greater risk for making poor choices for substance use. Academic performance outcomes, including grades earned in core subject areas of math, English, science and social studies, plus performance on state and national achievement tests, attendance rates and reduced tardiness show significantly positive improvement with the later start times of 8:35 AM or later. Finally, the number of car crashes for teen drivers from 16 to 18 years of age was significantly reduced by 70% when a school shifted start times from 7:35 AM to 8:55 AM.


So, how much sleep does a teenager need?  Jan Hoffman reveals what the sleep experts say:

Researchers have found that during adolescence, as hormones surge and the brain develops, teenagers who regularly sleep eight to nine hours a night learn better and are less likely to be tardy, get in fights or sustain athletic injuries. Sleeping well can also help moderate their tendency toward impulsive or risky decision-making.

During puberty, teenagers have a later release of the “sleep” hormone melatonin, which means they tend not to feel drowsy until around 11 p.m. That inclination can be further delayed by the stimulating blue light from electronic devices, which tricks the brain into sensing wakeful daylight, slowing the release of melatonin and the onset of sleep. The Minnesota study noted that 88 percent of the students kept a cellphone in their bedroom.


And how many hours does the average teenager really get?  Less than that, surveys tell us.  Hoffman tells us why sleep is so important for young learners:

Many researchers say that quality sleep directly affects learning because people store new facts during deep-sleep cycles. During the rapid-eye-movement phases, the brain is wildly active, sorting and categorizing the day’s data. The more sleep a teenager gets, the better the information is absorbed.

“Without enough sleep,” said Jessica Payne, a sleep researcher and assistant professor of psychology at the University of Notre Dame, “teenagers are losing the ability not only to solidify information but to transform and restructure it, extracting inferences and insights into problems.”


Is starting the teenagers’ day a little later going to help?  Or will they just stay up a little later?  Since this experiment has already been put into motion elsewhere — and may get a chance locally soon — only time will tell!


(Read more PediaBlog contributions by Dr. Donnelly here.)