By Amanda Ferguson, MA, Ph.D. Candidate
Much has changed in the last year. Many of us have started spending more time at home – working from home, learning from home, and socializing (virtually) from home. You’ve likely always slept at home, but take a moment to reflect – has your sleep routine changed alongside these other routines? If the answer is yes, you aren’t alone. In a recent study of sleep habits during the COVID-19 pandemic, 57% of respondents reported that they are going to bed later or much later than usual (i.e., before the pandemic), and 50% reported that they are waking up later or much later than usual.
There are lots of environmental and social reasons that people stay up late. There are some biological and genetic ones too. Adolescents, for example, have a different circadian rhythm from their younger siblings and may have an especially hard time “going to bed at a reasonable hour”. The part of the brain that regulates sleep, called the suprachiasmatic nucleus, shifts forward in timing during puberty, often past the timing of adults. So, while a nine year old’s circadian rhythm would probably have them sleeping by around nine o’clock at night, that same individual at sixteen years old will have no interest in sleeping at nine p.m. – they may actually be experiencing peak wakefulness at that hour. When most parents are getting tired around ten or eleven p.m., some teenagers (and night-owl-adults) might still be wide awake and waiting for their sleep signals to kick into gear.
Many of us wake up earlier from Monday to Friday than we do over the weekend, because during the week we have to get to work or school by a certain hour, and on the weekends we don’t. This pattern might feel especially familiar for teenagers, since their circadian rhythms are often shifted such that they prefer to go to bed later despite early morning school classes. Late bedtimes and early waking mean less time actually sleeping during the week. To compensate, people sleep in on the weekends or find themselves napping to “catch up”.
This misalignment of sleep timing across the work week and the weekend is known as “social jetlag”. Adolescents appear to experience more social jetlag than adults, possibly because of their shifted circadian rhythms. Of course, people are rarely in control of their child’s school start time, or when they have to be at work. There are still a few things you can do to create a healthy sleeping environment at home.
1) Turn down the lights. When exposed to light at different times of day, all circadian clocks can respond with advances or delays. Light exposure during the evening is more likely to produce sleep phase delays (i.e., going to bed later). Even incandescent home lighting has been shown to delay the release of melatonin (and thereby delay the onset of sleep). If you’re not sleepy at night, a good start is to create lowered, dim light in the rooms where you spend your evening hours, and to avoid powerful overhead lights.
2) Get a blue light filter for all devices. Our eyes have light receptors which communicate with the suprachiasmatic nucleus, our brain’s “internal clock”. The receptors responsible for sending the message “it’s daytime” are most sensitive to short-wavelength light within the blue spectrum, which is exactly the type of light produced by blue LED lights. Consequently, blue LED light in the evening has twice the harmful impact on nighttime melatonin suppression than the warm, yellow light from incandescent bulbs, even when matched for brightness.
Our electronic devices are strong emitters of blue LED, and many of us nonetheless use these devices shortly before going to bed. Reading on a tablet before bed has been shown delay the rise of melatonin by up to three hours, and consequently delay sleep onset (compared to reading a printed book). Importantly, electronic device use has been shown to change sleep quantity and quality above and beyond the timing of melatonin. One study found that individuals who were reading on a tablet before bed experienced less REM sleep, reported feeling less rested and sleepier throughout the day than they did when reading a printed book instead.
3) Keep it cool.Your core temperature needs to decrease by about 1 degree Celsius in order to initiate sleep. This is why many of us find it easier to fall asleep in a room that is too cold than too hot.As your core temperature decreases in the evening, your brain gets the message that sleep is approaching. Ideally this message will be received in the context of naturally fading light (or dimming artificial light – see 1 and 2 above!). These signals allow the suprachiasmatic nucleus to initiate the evening surge in melatonin (and soon after, sleep).
And perhaps most importantly:
4) Radical acceptance. Take some of the pressure off your sleep.The goal is not to have perfect control of your environment, so that you never miss a wink again. That is not the goal because that is not reality – there are a hundred (or more!) things that can affect any one night. Sometimes you have to keep the lights on. Sometimes it’s hot. Sometimes you’re online all day and have trouble winding down. All of that is ok. Practice noticing your tension or wakefulness without judgment – what does it actually feel like (e.g., in your body) to be restless? Practice noticing your thoughts and labeling them, then letting them go. Practice self-soothing and compassion by letting yourself rest even when you can’t sleep.
References
Mathew, G. M., Hale, L., & Chang, A. M. (2020). Social jetlag, eating behaviours and BMI among adolescents in the USA. British Journal of Nutrition, 124(9), 979-987.
Pinto, J., van Zeller, M., Amorim, P., Pimentel, A., Dantas, P., Eusébio, E., … & Drummond, M. (2020). Sleep quality in times of Covid-19 pandemic. Sleep medicine, 74, 81-85.
Walker, M. (2017). Why we sleep: Unlocking the power of sleep and dreams. Simon and Schuster.
Wittmann, M., Dinich, J., Merrow, M., & Roenneberg, T. (2006). Social jetlag: misalignment of biological and social time. Chronobiology international, 23(1-2), 497-509.
Yuksel, D., McKee, G. B., Perrin, P. B., Alzueta, E., Caffarra, S., Ramos-Usuga, D., … & Baker, F. C. (2021). Sleeping when the world locks down: Correlates of sleep health during the COVID-19 pandemic across 59 countries. Sleep Health.
Zerbini, G., Kantermann, T., & Merrow, M. (2020). Strategies to decrease social jetlag: Reducing evening blue light advances sleep and melatonin. European Journal of Neuroscience, 51(12), 2355-2366.
Image
Lach, R. (n.d.). Tired. Pexels. https://www.pexels.com/photo/woman-in-white-dress-shirt-sitting-on-black-couch-8487206/.