Written by: Alina Yu
With the hustle and bustle of classes, constant schoolwork, and maintenance of a social life, college students often slack off getting the necessary beauty sleep each night or revert to an abnormal nocturnal lifestyle. While we all know sleep is something we crave for when it is pitch black outside, sometimes we experience those random moments where our bodies seem to shut down, and our eyes begin to droop into a midday nap.
What is the true science behind sleep and why it is part of our human nature? We aim to dive deep into the body during sleep and understand how quintessential parts of the college lifestyle could have an impact on achieving the best sleep.
How does my body sleep?
What is actually happening when we go to sleep? Sleep is known to be the period for “rest and recharge” because our bodies physically go into limbo and are programmed to regenerate. To maintain our overall health, sleep provides our brain with the time to recover from daily metabolic processes that convert our bodily intake of nutrients and water into energy in order to improve our performance the next day. During the day, our bodies produce serotonin, which is well-known for its ability to trigger feelings of happiness, in reaction to sunlight, and a variety of other hormones like dopamine work in conjunction to help us stay awake. However, as the sun begins to set and the moon takes its place, our bodies produce serotonin’s sister hormone: melatonin. Melatonin, a hormone that our brains produce in response to darkness and is suppressed by light, binds to receptors in the body to help us relax in preparation for sleep. This hormone also binds to receptors in the brain to reduce neural activity by regulating body temperature and blood pressure. The cycle of hormone levels contributes to our body’s 24 hour internal clock, also known as the circadian rhythm.
During sleep itself, our bodies go through a series of four stages. Stages 1 to 3 are considered the non-REM (rapid eye movement) stages, where our bodies begin to “shut down” and our brains transition into sleep. In Stage 3, we enter deep sleep, and in Stage 4, our bodies go into REM sleep. During this stage, we experience muscle paralysis because of the release of inhibitory neurotransmitters, which act as keys that essentially lock skeletal muscle neurons in place and block them from activating our muscles. This stage of true sleep is characterized by the interaction of multiple neurotransmitter systems and the activity of key brain centers like the subcoeruleus nucleus, hypothalamus, forebrain, and brainstem. Our brains remain active as we lie inactive for what is ideally 7 to 9 hours each night. However, our circadian rhythms and the quality of our four stages of sleep can be greatly impacted by not only our choice to sleep or not but also multiple environmental factors we incorporate throughout our daily lifestyles.
Does screen time really affect my sleep quality?
One huge component in the 21st century lifestyle is technology, especially our mobile devices. Screens surround us in our homes, buildings, and transportation. We use phones, tablets, computers, desktops, and TVs constantly throughout our lives. And as we consider our screen time more in a pandemic world, especially with Zoom feeling like our friend and foe, we should also be wary of the times when our screens might infringe into valuable sleep time. Researchers from New York have found that even children and adolescents use screens well into the night, with 60% using devices within an hour before bedtime.
Screens emit blue light, a type of light that is emitted along the blue wavelengths similar to those that stimulate our brains during daylight hours. As previously mentioned, light represses the production of melatonin by the brain, and thus with the prolonged use of screens into the night, our brain is constantly being exposed to some type of light stimulus. While viewing our screens, we are more attentive and reactive and not the relaxed state needed for sleep; this hyper-stiumlated state can thus delay our natural circadian rhythm. So when is it a good time to shutdown the screen, despite the late-night exam cramming or paper-writing session?
Studies have shown that setting limits to screen use after a certain time at night have been effective at increasing sleep time and improving quality of sleep. The recommended amount of time before bedtime to avoid looking at screens varies. Some studies have suggested 30 minutes to an hour before bedtime to reduce looking at screens or avoid screens in general. Devices have also developed a night shift mode to help reduce the amount of blue light exposure.
Should I cure my caffeine addiction?
Another key player in many lives, whether in college or not, is caffeine. Whether it be a cup of coffee or nice soothing tea, caffeine can come in so many forms and is even naturally present in our bodies. Caffeine is a stimulant that our bodies naturally produce that is included in the methylxanthine class of molecules, which have similar structures to that of amino acids. That being said, caffeine or your impending coffee addiction, acts as a stimulant on receptors that primarily are associated with sleep, arousal, and cognition in the brain. So while caffeine is a great booster to start your day, drinking or ingesting copious amounts into the evening hours could affect not only your circadian rhythm but also the actual quality of your sleep.
Caffeine consumption during the day can have lasting impacts in the night. A reduction in 6-sulfatoxymelatonin, a component of melatonin, can cause sleep interruption and interrupt your ability to get a full sleep cycle. Studies have found that doses of caffeine even 6 hours prior to bedtime had an impact on quality of sleep, shifting the REM and non-REM sleep stages. Therefore, whether you take caffeine in coffee or an energy drink, drinking doses under 400 mg (equivalent to four cups of coffee) and restricting caffeinated beverage consumption to earlier in the day can help to reduce sleep disturbances.
Can I still schedule my naps in?
Finally, the staple of any college student’s life: naps. Typically used to countermeasure sleepiness and impaired performance, naps are sometimes the go-to remedy for any late night or sleep deprivation. However, how truly effective are they, and what are the effects naps have on actual sleep quality and our internal clock?
Many studies have shown that naps that are 30 minutes or less have been proven to be more effective at achieving sleep remedy without negative side effects. One side effect is sleep inertia, or the feeling of grogginess and mental fog after waking up from a nap. Oftentimes, prior sleep loss can impact sleep inertia, which more heavily impairs active performance and induces further extended wakefulness. The occasional power nap can get the job done, but habitual napping can have more harmful long-term physiological effects than expected.
Overall, there is much to consider in your daily routine when trying to orient towards a more healthy sleep schedule. External and internal chemical stimulants can have a great impact on the sleep-inducing hormone levels your body naturally produces. Setting consistent sleep and wake-up times can be beneficial, along with screen time limits to avoid exposure to blue light within a certain time frame before sleep. Limiting caffeine intake to an equivalent one or two cups of coffee before noon can help maintain sound sleep in the evening. Everyone’s bodies react differently, so it is important to find a daytime routine that works best for you in order to have the most restorative nighttime routine of sleep.
