“GOING TO bed early is like admitting my defeat,” says Lee Ju-hee, a junior in high school. “The more I sleep, the more I feel like I’m lagging behind.” The competitiveness in today’s modern society has contributed to the idea that sleeping is a waste of precious time which could be spent more productively. Sleep deprivation has become a social norm among the younger generation, and university students are especially prone to this phenomenon. Pulling an all-nighter before an important exam, staying up until three in the morning to finish a paper, and chugging coffee to compensate for last night’s lack of sleep are all situations that university students face on a daily basis.
According to statistics provided by the Ministry of Health and Welfare, an average Korean in his or her twenties sleeps less than seven hours a day. The important thing to note is that most people acknowledge that they are sleep deprived, but have a shallow understanding of how detrimental sleep deprivation is to an individual’s health in the long run. Preventative methods desperately need to be incorporated into everyday life to avoid critical health consequences, and to do that, it is important that people make an effort to understand the role sleep plays in mental and physical health.
The science behind sleep
The common sleep cycle is comprised of 5 stages and lasts for roughly 90 minutes. The sleep cycle occurs in intervals and its stages are divided according to the presence of rapid eye movements. The first four stages are referred to as non-rapid eye movement (N-REM) sleep, and the remaining fifth stage is called rapid eye movement (REM) sleep. During the four stages of N-REM sleep, a person drifts from a very light sleep in stage 1 to a very deep sleep in stage 4. As the name suggests, the eyes do not move during this stage, but other muscles are still able to function.
REM sleep is the final stage of the sleep cycle, the stage in which a person experiences rapid eye movements. The eyes randomly dart sideways, upwards and downwards, and most of the body’s muscles are paralyzed. This is the deepest stage of sleep, and the stage where most dreaming occurs. Although the body is paralyzed, the brain continues to function as neural activity changes drastically from a slow wave to a more random and rapid pattern. Mental recovery occurs during REM sleep, whereas N-REM sleep is more associated with physical recuperation. Understanding the sleep cycle is crucial to determining if one is experiencing normal or disordered sleep*.
Sleep disorders can be largely divided into four categories: insomnia, excessive daytime sleepiness, sleep rhythm problems, and sleep-disruptive behaviors. Insomnia refers to problems in falling and staying asleep, while excessive daytime sleepiness is associated with problems in staying awake. University students typically have problems sticking to a regular sleep schedule, which is related to sleep rhythm problems. An individual may have a combination of all four sleeping disorders, which would all contribute to sleep deprivation**.
Lack of sleep affects everyday performance
Although sleeping disorders are not uncommon, Professor Chu Min-kyung of the Severance Hospital Department of Neurology says that the habit of sleeping late is a much more common cause of sleep deprivation among younger generations. “Young people in their late teens and twenties tend to have a habit of going to bed late at night,” said Professor Chu in an interview with The Yonsei Annals. “This lifestyle not only reduces the quantity and quality of sleep, but can also disturb a person from developing a regular sleep schedule, which is imperative to one’s health.”
Specific numbers vary from study to study, but a majority of researchers state that an average adult needs 8 to 9 hours of sleep a day. Professor Chu recommends 7 hours of sleep a day, 6 hours at the bare minimum. However, a statistical report released by the Korea Centers for Disease Control & Prevention*** state that Koreans aged 19 and above get an average of only 7 hours of sleep per night.
Short-term symptoms of sleep deprivation are well-known since they are immediately recognizable the next day. Fatigue, lack of concentration, irritability, and slurred speech are some of the most common among such symptoms. A combination of these symptoms can affect everyday performance, reducing work efficiency and increasing risk of accidents.
In the long run, lack of sleep affects both cognitive and physical health. “The body and mind recharge during sleep,” said Professor Chu. “Because sleep and mood are closely connected, chronic sleep loss can potentially lead to mental health issues like anxiety and depression.” The professor further emphasized that in the long run, sleep deprivation significantly increases risks of heart disease and cancer. “This is because melatonin, a hormone that is produced while we sleep, is an anti-cancer agent that inhibits the growth of certain cancer cells such as breast cancer,” explained Professor Chu. “Hence, insufficient sleep leads to reduced levels of melatonin, which subsequently causes risks of diseases to increase by a substantial amount.”
The effects of prescriptive drugs and over-the-counter medications
Symptoms of sleep deprivation cause some people to resort to medication. “A habitual, inconsistent sleep schedule often results in insomnia,” said Professor Chu. “Consequently, many choose to intake prescription drugs that induce sleep by reducing anxiety.” According to the professor, antidepressants, sleeping pills, and mood stabilizers are some of the most common types of prescribed medications used to treat patients.
Although sleeping pills may be effective in inducing sleep, Professor Chu emphasized that such drugs do not ensure good-quality sleep. “It's like treading water,” he said. “You manage to sleep, but drugs do not solve the root of the problem.” Moreover, prolonged use of sleeping medications can result in the loss of memory, self-control, and emotion regulation.
Over-the-counter medications differ from prescriptive sleeping drugs in that they are milder and pose lower risks of side effects. “Their substances are different,” elaborated Professor Chu. However, regular use of non-prescription sleeping aids containing antihistamine still puts people at risk for side effects such as nausea and blurred vision. Thus, it is strongly advised that patients consult a doctor before taking such medications.
Preventing sleep deprivation by natural means
Due to the potential drawbacks of sleeping pills, it is important to prevent and treat sleep deprivation through natural means. Professor Chu strongly advises developing a regular sleep schedule. “It seems quite obvious, but going to sleep and waking up at an assigned time is the best method to prevent or treat sleep deprivation,” he said. Acknowledging this is not an option for all, Professor Chu proposed the next best alternative: catching up on lost sleep. “This concept is also known as repaying sleep debt,” explained the professor. “Sleep debt” is a term that refers to the effects of cumulative sleep loss. “If you missed eight hours of sleep over the course of a week, get some extra hours of sleep during the weekend to pay off your sleep debt.”
Short naps that last less than an hour are not as effective. “The body needs at least an hour of deep sleep for recovery to take place,” said Professor Chu. “Rather than taking short, 20-minute naps throughout the day, it is much better to combine all of those brief naps to sleep for at least a solid hour.”
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Sleep tends to be one of those things that we take for granted. Everyone knows that a lack of it causes negative health consequences to some degree, but what a majority of people fail to realize is that chronic sleep loss can result in some critical health risks like heart disease and cancer. A majority of health issues spark from sleep deficiency, a problem that can be resolved if one puts effort into prevention and treatment. Sleep deficiency is not a light concern that can be shrugged off. Make a personal effort to ensure that your body is getting the proper amount of sleep, or actively seek professional help. Above all, it is crucial to regard sleep not as an obstacle that delays work, but as an essential process to success.
**Severance Hospital Sleep Health Center
***2016 National Health Statistics Report, published in 2018 by the Korea Centers for Disease Control & Prevention