We're a puritanical society when it comes to sleepinglate in the morning. We equate having a lie-in tobeing a lazy good-for-nothing. Teenagers inparticular suffer at the hands of such ignorantcriticism.
The fact is, teens can no more bounce out of bedearly in the morning than you can run 100m in 10 seconds. We've known for some time that theteenage brain literally "deconstructs", meaning that brain connections are broken, brainrhythms are disrupted and brain centres don't function. Crucial among those lost functions isa broken body clock.
It's still a 24 hour clock but it's not in sync with day and night. This means teens don't want togo to sleep until after midnight and don't want to wake up until late morning. For virtually alladolescents, the secretion of melatonin (the body clock's sleeping pill) doesn't begin until about11pm and continues until about 8am. This means that most teenagers simply can't fall asleepuntil this secretion begins, and find it impossible to wake up until the melatonin turns off.
This fixed pattern of melatonin secretion in teens doesn't normalise until they're in their 20s. So the unique sleep/wake pattern of teenagers is beyond their control. What bothers me isthat the biology of the teen brain is in direct conflict with school timetables, which stipulatean early start for adolescents. The result is they become sleep deprived.
There are serious consequences if teens fail to get adequate sleep. Those who are sleep deprived - defined as getting less than eight hours per night - are more likely to smoke, drinkand take drugs. With less than nine hours of sleep per night, depression among teens risessignificantly. Research shows around half of teenagers who sleep four hours or less per nightfeel sad and hopeless, compared to just a fifth of those who sleep longer.
Teen car crashes, the primary cause of death for this age group, significantly decline whenteens obtain more than eight hours of sleep per night. Later school start times are one answerand results are encouraging. The students do, in fact, get more sleep, tending to go to bed atthe same time but getting up a bit later.