How Does Your Smartphone Affect Your Sleep?
Using smartphones before going to bed can disrupt your sleep quality and duration.
Using smartphones before going to bed can disrupt your sleep quality and duration.
Lack of sleep is one of the biggest, most universal problems faced by people all around the globe. Healthy adults need at least 7-8 hours of sleep per night. A consensus among specialists states that adolescents have a slightly higher need, with a minimum of 8.5-10 hours of sleep each night to feel good and function at the top of their ability, with younger adolescents typically requiring closer to 10 hours. However, study after study proves that the average of sleep that adults and adolescents get in reality cuts at least one hour short, especially in adolescents, whose sleep time fits in a range between 7.5-8.5 hours in more relaxed periods, 6.5 hours or even less on weekdays.
This lack of sleep occurs due to many factors, including stress, high academic demands, an abundance of homework, the early school start opposing to the naturally later circadian sleep rhythm common in adolescents, and the list goes on. Note that adolescents need a lot of socialization during this developmental phase as well, but often get a very small time window (if any) to engage in such activities outside of school, swamped with responsibilities as they are. The ultimatum is created between sleep and socialization almost daily, and many adolescents will choose the latter, leading to poor sleep hygiene and many potential issues.
This decision is only reinforced by the surge of technology over the last decade and a half. With the constant availability and connectivity of modern devices to everybody and every place, it is easier than ever to fill that gap by casually chatting with a friend or falling down a YouTube rabbit hole from the comfort of our own homes, even beds. At this point, it is safe to assume that the thought of the potentially harmful effect of the increasingly prolonged screen time has crossed most people’s minds; to find out the legitimacy behind such thoughts and the extent of harm inflicted by such behavior, keep reading.
Many people nowadays take their phones with them wherever they go, at all times. We check up on social media feed, snap photos of our meals, text on-and-off, scroll through the news and look for directions to places we haven’t been to before. Immediately from the alarm ring in the morning, smartphones are often the first thing we reach for when we wake up and the last thing we “do” before we fall asleep. In fact, research shows that around 71% of people keep their phones within arm’s reach or in the bed at nighttime, regularly falling asleep with the phone in one hand. Even more staggering is that between 40-47% of adolescents wake up shortly after falling asleep to answer a text or call and are shown to be sensitive to their phones’ notification sounds the same way mothers are sensitive to their babies’ cry.
When you use your cell phone as an alarm clock, it makes sense that you would want to keep it close by, but the problem occurs with the temptation to check up on social media one last time before sleep – having your phone near you means you are most unlikely to resist that temptation. What starts as innocent surfing may soon wake you up completely as you read something that upsets you or engage in a conversation with a friend. Before long, instead of relaxing you and preparing for bed, this activity will stimulate you and effectively postpone sleep latency as a result. Many studies have examined the impact of such behavior on sleep and were unsurprisingly able to find a number of issues stemming from it. Bedtime use of smartphones in adolescents and adults alike was linked with lower sleep quality and later sleep onset, directly increasing risks for anxiety, depression and causing excessive daytime sleepiness. Using phones after turning off all other lights was linked with four different types of sleep disturbances, most prominently insomnia, and waking up to answer calls and texts resulted in up to an hour less of total sleep time.
Furthermore, hypervigilant response to the notification bell and the pathological usage of smartphones point to a behavioral addiction, especially in people akin to similar problematic behaviors. This doesn’t only negatively impact sleep. Spending an excessive amount of time in front of the screen puts one at a greater risk of many mental and other health conditions, lowers focus and the overall quality of life. This effect varies between the different ways one might use their phone, but general practitioners should be aware of this phenomenon and make sure to check on their patients’ technology use. Scrolling in particular delays one’s response time and has an addictive, rewarding effect on our brains: as we come across a piece of information that interests us, our brains receive the feedback that the action has paid off and reinforce such behavior. Over time, the overstimulation of this technology misuse negatively impacts various aspects of our lives, displayed in worsened academic performance, lower learning ability, shorter focus span, and heightened irritability when such an activity is unavailable. The full range of consequences of the excessive screen use on a global level is yet to be fully encompassed. But besides their purpose as distractions (as well as tools), screens, or screen lights to be precise, have a spectrum of adverse effects of their own when it comes to our health.
Most of the technology we currently use emits blue light, known for having the shortest wavelength in the visible range, between 400-495 nm. This means that its intensity easily pierces through our retinas’ photoreceptors and it has the greatest ability to set and reset human circadian rhythms. Circadian rhythms are processes in our body that have control over the timing when some other processes will take place during the period of 24 hours. Our core body temperature fluctuations and feeding times are both controlled by two such rhythms, and so is sleep. Based on light exposure we receive during the day, our circadian rhythm makes sure that we are awake when it’s daytime and sleep during the night. Accumulating evidence suggests that artificial blue light as emitted by technology may disrupt the natural functioning of the circadian rhythm, and has a negative effect on various physiological processes when exposure is high and at a later time of day.
Most of our exposure to this light comes from flatscreen TVs, tablets, computers, and smartphones, along with LED (light emitting diode) lights. The use of self-luminous devices in the evening has been proven to suppress one’s natural melatonin secretion and thus prolong their time awake, over time potentially causing insomnia or some other sleep-related disorder. A UK-based study published in January 2019 investigated the subject in the population group of 6616 young adolescents. Two-thirds of them reported using technology at nighttime which was associated with a higher chance of later sleep onset and an insufficient amount of sleep. Those who used phones or watched television with another light on at bedtime had a poorer overall efficiency of sleep than adolescents who didn’t use technology at this time, while those who used some of these devices in darkness had the worst sleep quality of the group, and an insufficient duration of sleep. Thankfully, many newer models of tablets, computers, and smartphones now come with a blue light filter which helps reduce the damaging effects explained above.
Contrary to what you may be thinking by now, blue light isn’t always harmful. It is just its intensive use and bad timing that make it such an issue. In fact, when turned around and properly timed, blue light can be used to our advantage, too. Phototherapy, or light therapy, is one such use of blue (in combination with white) light to treat the very disorders its evening misuse can cause. It works by suppressing melatonin production and cueing for the circadian rhythm to alert one’s body, thus promoting a healthy, orderly cycle. It is usually used in the morning to help patients wake up and maintain their alertness. Though, in cases like the advanced sleep-wake phase disorder, which causes one to fall asleep and wake up hours earlier than average, it can be used later during the day as well, to prolong wakefulness if necessary. Light therapy is used to treat a seasonal affective disorder, jet lag, and many other sleep disorders, often in combination with other treatment methods like sleep restriction therapy.
Smartphones are undoubtedly able to serve many useful purposes in our lives. As long as we know how to keep a certain distance, we can maintain a healthy relationship with them and not at the cost of sleep. While limiting screen time doesn’t sound appealing at first, the benefits can be significant. Below are some tips to help motivate you in such attempts.
Michael is a professional writer based in Boston and someone who has always been fascinated with the mysteries of sleep. When he’s not reading about new sleep studies and working on our news section, you can find him playing video games or visiting local comic book stores.