Quick Facts for Teens/Parents

Biology of Sleep for Teenagers

1. Teenagers have a biological tendency to go to sleep later, as much as two hours later, than their younger counterparts.   Their natural time for bed is around 10:45 pm and the brain remains in the sleep mode until about 8:00 am.

2. Teens are biologically more alert in the evening. This makes it difficult or impossible to fall asleep early enough to obtain the 8-10 hours of sleep recommended before having to wake early for school.

3. Teens try to make up for lost sleep by sleeping in on the weekends. This shifting schedule in sleep pattern from the school week to the weekend, affects the rhythm of the “master clock.” The master clock is in the brain. There are “organ clocks” as well, in the liver, kidney and lungs. The master clock is the leader. When this master clock becomes out of sync due to the shift in sleep schedule, the organ clocks become disoriented as well.

Important Facts about Sleep

1. Sleep is needed for memory and learning. Teenagers perform better on mental tasks when they are well rested. Sleep allows the brain to act as a filter, retaining the important things and filtering out those unimportant things that happened during the daytime.

2. Teenagers are not dreaming as much as they once did. They are waking up for school during the time they would normally be having the dream-rich, rapid eye movement (REM) stage of sleep.

3. Lack of deep sleep reduces the ability to remember positive memories, causing mainly negative memories to be retained.

4. Teens who are sleep deprived need up to two weeks of sleep without forced awakening to eliminate their “sleep debt” due to insufficient sleep on school days. Weekend “oversleep” is insufficient to erase the sleep debt from a week of early rising.

Consequences of Sleep Loss

Mental Health

– Sleep deprivation causes a higher risk for suicide, even if the teenager is not depressed or using alcohol.

– Sleep loss leads to emotional outbursts, behavioral problems, anxiety and depression. Obtaining the right amount of sleep can act as a buffer and help prevent the downhill slide to these issues.

– A teenager getting less than 8 hours of sleep per night is significantly more likely to use cigarettes, alcohol, drugs and be sexually active.

Physical Health/Safety

– Sleep loss affects appetite, metabolism and weight gain for teenagers.

– Car accidents are the #1 cause of death for teenagers and starting high school before 8:30 am is associated with higher car accident risk for teen drivers. Brain impairment with insufficient sleep is similar to alcohol intoxication, with reduced reaction times, awareness of traffic and the ability to remain alert.

– There is a higher risk of sport injury in a teenager who is sleep deprived.

Academic Performance

– Less sleep is associated with poorer test scores and reduced academic performance. Academic performance improves with a later school start time.


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