By Andrea DeBrish
Do you stay up late at night? Do you sleep in on the weekends? You might be suffering from what is referred to as social jetlag.
A persons sleep pattern, the time they naturally want to fall asleep and wake up, is their chronotype. This is regulated by a person’s circadian rhythms. That is the 24 hour pattern a person’s bodily functions follow based off of the daily rotation of the earth. This circadian biological clock is controlled by part of the brain called the Suprachiasmatic Nucleus (SCN). The SCN is located in the part of the brain known as the hypothalamus and is largely stimulated by signals of light and dark. Light signals the SCN for the release of hormones including cortisol and raising of the body temperature. Light also suppresses levels of melatonin which is a hormone involved in falling and staying asleep.
The two general chronotypes are the early chronotype and late chronotype referring to the relative natural time at which they would like to wake up in the morning. The late chronotype is more common in the population but in many industrialized societies, there is an early social schedule where work and school days typically start at 8am. People with the late chronograph, often referred to as owls, cannot fall asleep early enough get ample sleep before rising in the morning to make it to work on time. They can then accrue a sleep debt of lost hours. To make up for this debt, they will often sleep in late on the weekends, trying to reduce their fatigue. This creates the jetlag effect where on the weekend they have effectively gone west a couple of time zones and then come back for the work week.
Social jetlag can especially be a problem for teenagers who naturally experience a sleep phase delay. This means they often have trouble getting to sleep before 11pm and then the social clock requires them to be up and ready for school at 8am. This does not leave enough time for them to get the sleep they need.
There are other problems and behaviors which can be associated with social jetlag aside from tiredness. It has been shown to correlate with caffeine and alcohol consumption in addition to tobacco use. This can be especially problematic when there is such an increased chance for social jetlag among teenagers. Late chronotypes have also shown less general feelings of well being and increased psychological disturbance which can also be especially problematic among teenagers.
Another study done showed a relationship between obesity and social jetlag. Not getting enough sleep increased a person’s probability of being obese. Both sleep timing and duration related to metabolism.
It has long been known that sleep is important for a well functioning, healthy human. It is now becoming more apparent though how our artificial system of time can have negative effects on healthy sleep patterns. By having designated work and school hours starting at 8 am people are being forced to work against their natural sleep patterns to their own detriment.
There may be a movement in the future for companies to be more flexible with scheduling to allow people to work within their own circadian rhythms. This could perhaps even lead to greater productivity of their employees if they aren’t completely exhausted all the time. It would also be good for schools to recognize the sleep phase delay in teenagers and adjust their times accordingly as well. It would also help to remove the system of daylight savings time which effectively messes up everyone’s internal clocks twice a year.
Until the social clocks can get changed, there are some things a person can do to help ease their own social jetlag. One is exposure to bright light right upon waking up. This light signals the SCN which sends other signals out to express all the right hormones to wake up. This is using the cues we get from nature to our advantage. Another step to help is to turn lights down before bed and avoid work or any other mentally taxing activity which could keep you from falling asleep. It’s also important to try to keep the same schedule for everyday so your body can attempt to reset its internal clock.
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Wittmann, M., J. Dinich, M, Merrow, and T. Roenneberg. 2006. Social Jetlag: Misalignment of Biological and Social Time. Chronobiology International 23(1&2):497-509