We all know that we need sleep to live but how exactly does sleep help us live? What's even going on in our bodies when we go to bed every night? Sleep is important beyond helping you feel alert the next day- there are long-term effects you may not realize impact your life.
Life as a student can feel at times like you are running a marathon. You have back-to-back classes and activities, and, at times, barely enough time to eat. As most of us know, this lifestyle means you need to be in your best shape possible to handle this strenuous schedule. But what many people don’t realize is that sleep is critical to this marathon-like lifestyle beyond just helping you feel alert the next day. Without enough sleep, it is harder to stay healthy and retain stamina throughout life’s marathon. The following module shows how sleep can impact your physical well-being in the short and long term.
Sleep is critical for your overall health. In fact, according to Get Sleep, the website for the Division of Sleep Medicine at Harvard Medical School, sleep is just as important for your health as regular physical activity and a healthy diet. Partial sleep deprivation is associated with weight gain (to see why, check out our module on food and sleep), linked to a higher risk for type 2 diabetes and cardiovascular disease, and reduced immune function (GetSleep). Studies have also shown that consistently sleeping less than 5 hours a night is associated with an increased mortality risk (GetSleep). Although these diseases might not seem particularly relevant to you as a young college student, an extremely pertinent part of the college experience is the common cold, which has been associated with a lack of sleep (Prather et al., 2015).
GetSleep (n.d). Sleep and Health. Retrieved July 2020, from http://healthysleep.med.harvard.edu/need-sleep/whats-in-it-for-you/health#9.
In a study conducted between 2007 and 2011, Prather, Janicki-Deverts, Hall, & Cohen were looking to see if there was an association between sleep and catching the common cold. They measured sleep patterns through actigraphy for 164 participants over the span of 7 days before exposing them to rhinovirus (a virus that induces the symptoms of the common cold). The study found that those who were sleeping less than 6 hours as measured by the actigraph had a greater likelihood of fostering a clinical cold (defined by the study as getting infected with the virus and showing symptoms). Thus, robbing yourself of the sleep you need is associated with more than just being tired in the morning: it is linked to worse health outcomes.
Prather, A., Janicki-Deverts, D., Hall, M., & Cohen, S. (2015). Behaviorally Assessed Sleep and Susceptibility to the Common Cold. Sleep, 38(9), 1353-1359.
While some of these risks like the common cold can be seen as short-term effects, if you routinely do not get the sleep your body needs, the long-term negative results can take a toll on your physical body as well as your mental and emotional state. Our brains are magnificently hard workers, using ¼ of the body's entire energy supply, while accounting for just 2% of the body's mass. They need time and space to rest and repair. In a sense, this is what your brain is doing when you go to sleep.
Every cell in our body requires nutrients to fuel it and, as a byproduct, every cell produces waste that the body needs to get rid of. Normally, our bodies use the lymphatic system to process nutrients by taking proteins and other waste from the spaces between the cells and dumping them into the blood to be disposed of. But there are no lymphatic vessels in the brain… so how does this unique organ receive and, perhaps more importantly, rid itself of waste? New research suggests it has to do with sleep!
Iliff, J. (2014, September) One More Reason to Get a Good Night's Sleep [Video file]. TED. www.ted.com/talks/jeff_iliff_
There are other, less intuitive ways that sleep can affect your health besides getting sick. One that may not immediately come to mind is car accidents. Taylor & Bramoweth collected a week’s worth of sleep diaries from 1039 college students. They found that not only is insufficient sleep common, but also that 16% of the surveyed students said they fell asleep while driving. 2% stated they got into an accident involving a car because of sleepiness.
Taylor, D. J., & Bramoweth, A. D. (2010). Patterns and consequences of inadequate sleep in college students: substance use and motor vehicle accidents. Journal of Adolescent Health, 46(6), 610-612.
Although this trend may be more common in college students as they are a population known for getting inadequate sleep, it is certainly not a trend exclusive to college students. The National Highway Traffic Safety Administration compiled a 5-year average of drowsy driving statistics from 2011 through 2015. They found that 2.5% of fatal car crashes involved drowsy driving and that an average of 824 people died due to car crashes involving drowsy driving from 2011-2015.
National Center for Statistics and Analysis. (2017, October). Drowsy Driving 2015 (Crash•Stats Brief Statistical Summary. Report No. DOT HS 812 446). Washington, DC: National Highway Traffic Safety Administration
There are many things you can do to avoid drowsy driving. The first being getting adequate sleep, especially before driving a motor vehicle. You can also watch for the signs of drowsy driving detailed by the CDC to prevent a drowsy induced accident:
- "Yawning or blinking frequently.
- Difficulty remembering the past few miles driven.
- Missing your exit.
- Drifting from your lane.
- Hitting a rumble strip on the side of the road."
Centers for Disease Control and Prevention. (2020, May 8). Drowsy Driving: Asleep at the Wheel. Centers for Disease Control and Prevention. https://www.cdc.gov/sleep/features/drowsy-driving.html
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