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Good Sleep for Good Health

Get the Rest You Need

Illustration of man shutting off light and getting in bed

Sometimes, the pace of modern life barely gives you time to stop and rest. It can make getting a good night’s sleep on a regular basis seem like a dream.

But sleep is as important for good health as diet and exercise. Good sleep improves your brain performance, mood, and health.

Not getting enough quality sleep regularly raises the risk of many diseases and disorders. These range from heart disease and stroke to obesity and dementia.

There’s more to good sleep than just the hours spent in bed, says Dr. Marishka Brown, a sleep expert at NIH. “Healthy sleep encompasses three major things,” she explains. “One is how much sleep you get. Another is sleep quality—that you get uninterrupted and refreshing sleep. The last is a consistent sleep schedule.”

People who work the night shift or irregular schedules may find getting quality sleep extra challenging. And times of great stress—like the current pandemic—can disrupt our normal sleep routines. But there are many things you can do to improve your sleep.

Sleep for Repair

Why do we need to sleep? People often think that sleep is just “down time,” when a tired brain gets to rest, says Dr. Maiken Nedergaard, who studies sleep at the University of Rochester.

“But that’s wrong,” she says. While you sleep, your brain is working. For example, sleep helps prepare your brain to learn, remember, and create.

Nedergaard and her colleagues discovered that the brain has a drainage system that removes toxins during sleep.

“When we sleep, the brain totally changes function,” she explains. “It becomes almost like a kidney, removing waste from the system.”

Her team found in mice that the drainage system removes some of the proteins linked with Alzheimer’s disease. These toxins were removed twice as fast from the brain during sleep.

Everything from blood vessels to the immune system The system that protects your body from invading viruses, bacteria, and other microscopic threats. uses sleep as a time for repair, says Dr. Kenneth Wright, Jr., a sleep researcher at the University of Colorado.

“There are certain repair processes that occur in the body mostly, or most effectively, during sleep,” he explains. “If you don’t get enough sleep, those processes are going to be disturbed.”

Sleep Myths and Truths

How much sleep you need changes with age. Experts recommend school-age children get at least nine hours a night and teens get between eight and 10. Most adults need at least seven hours or more of sleep each night.

There are many misunderstandings about sleep. One is that adults need less sleep as they get older. This isn’t true. Older adults still need the same amount. But sleep quality can get worse as you age. Older adults are also more likely to take medications that interfere with sleep.

Another sleep myth is that you can “catch up” on your days off. Researchers are finding that this largely isn’t the case.

“If you have one bad night’s sleep and take a nap, or sleep longer the next night, that can benefit you,” says Wright. “But if you have a week’s worth of getting too little sleep, the weekend isn’t sufficient for you to catch up. That’s not a healthy behavior.”

In a recent study, Wright and his team looked at people with consistently deficient sleep. They compared them to sleep-deprived people who got to sleep in on the weekend.

Both groups of people gained weight with lack of sleep. Their bodies’ ability to control blood sugar levels also got worse. The weekend catch-up sleep didn’t help.

On the flip side, more sleep isn’t always better, says Brown. For adults, “if you’re sleeping more than nine hours a night and you still don’t feel refreshed, there may be some underlying medical issue,” she explains.

Sleep Disorders

Some people have conditions that prevent them from getting enough quality sleep, no matter how hard they try. These problems are called sleep disorders.

The most common sleep disorder is insomnia. “Insomnia is when you have repeated difficulty getting to sleep and/or staying asleep,” says Brown. This happens despite having the time to sleep and a proper sleep environment. It can make you feel tired or unrested during the day.

Insomnia can be short-term, where people struggle to sleep for a few weeks or months. “Quite a few more people have been experiencing this during the pandemic,” Brown says. Long-term insomnia lasts for three months or longer.

Sleep apnea is another common sleep disorder. In sleep apnea, the upper airway becomes blocked during sleep. This reduces or stops airflow, which wakes people up during the night. The condition can be dangerous. If untreated, it may lead to other health problems.

If you regularly have problems sleeping, talk with your health care provider. They may have you keep a sleep diary to track your sleep for several weeks. They can also run tests, including sleep studies. These look for sleep disorders.

Getting Better Sleep

If you’re having trouble sleeping, hearing how important it is may be frustrating. But simple things can improve your odds of a good night’s sleep. See the Wise Choices box for tips to sleep better every day.

Treatments are available for many common sleep disorders. Cognitive behavioral therapy can help many people with insomnia get better sleep. Medications can also help some people.

Many people with sleep apnea benefit from using a device called a CPAP machine. These machines keep the airway open so that you can breathe. Other treatments can include special mouthguards and lifestyle changes.

For everyone, “as best you can, try to make sleep a priority,” Brown says. “Sleep is not a throwaway thing—it’s a biological necessity.”

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Why a Good Night’s Sleep Is Important for Your Health

  • Restoration
  • Stress Reduction
  • Body Weight
  • Illness Prevention
  • Mental Health

How to Improve Your Sleep

Sleep is important due to the impact it has on your overall health. Appropriate sleep is needed for mental focus and memory, managing stress, maintaining proper body weight, boosting the immune system, and a host of other wellness needs. Some studies suggest sleep can help to prevent illness, such as diabetes or obesity .

Adults aged 18 to 60 years should get at least seven hours of sleep each night in order to achieve the benefits of sleep. If not, you run the risk of becoming sleep-deprived .

This article explains the role of sleep in overall health and offers tips on how to improve your sleep. Research on sleep and sleep cycles has elevated awareness about sleep hygiene (healthy sleep habits) and the quality of sleep.

 Illustration by Emily Roberts for Verywell Health

Sleep Is Restorative

When you sleep, you allow your body to repair and rebuild. During this time, the body is able to clear debris from the lymphatic system, which boosts the immune system.

While you sleep, there are many important processes that happen, including:

  • Muscle repair
  • Protein synthesis
  • Tissue growth
  • Hormone release

Sleep Reduces Stress

Sleep is a powerful stress reliever. It improves concentration, regulates mood, and sharpens judgment and decision-making. A lack of sleep not only reduces mental clarity but the ability to cope with stressful situations.

This is due, in part, to changes in cortisol levels. Typically, your cortisol levels fall in the evening hours, as one element of the body’s natural preparation for sleep. When sleep is lost, cortisol levels remain high and interfere with the release of melatonin, a hormone that is essential for the regulation of sleep-wake cycles.

Some studies suggest these changes could even be used to evaluate depression in people with bipolar disorder. Other studies demonstrate a link between sleep, chronic stress, and depression with an eye on heart rate changes.

Sleep Improves Your Memory

The link between sleep and memory processing is well established. Sleep serves as an opportunity for the mind to process all the stimuli taken in while awake. It triggers changes in the brain that strengthen neural connections helping us to form memories.

Sleep quality is important when learning new information and using memory. Numerous research studies find that electrophysiological, neurochemical, and genetic mechanisms that take place during the slow-wave sleep stage of sleep are key.

Sleep Helps You Maintain a Healthy Body Weight

When you are sleep deprived, your body alters the hormones that regulate hunger and appetite. These hormones include:

  • Leptin: This hormone suppresses appetite and encourages the body to expend energy.
  • Ghrelin: This hormone triggers feelings of hunger.

Both of these hormones are thrown off when you are short on sleep—leptin goes down and ghrelin goes up. Obstructive sleep apnea , a serious sleep disorder, is linked with obesity as well.

Sleep and Appetite

Sleep deprivation can activate the endocannabinoid (eCB) system in the brain (the same areas activated by marijuana) which increases hunger and appetite. Stimulating the eCB reward system makes you more likely to crave junk food.  You are also more likely to make these unhealthy lifestyle choices when you are tired. If that's often the case, it can lead to weight gain or diabetes over time.  

Sleep May Prevent Illnesses

Sleep deprivation can have very detrimental health impacts and has been linked to chronic diseases such as diabetes and heart disease. Here are some of the health conditions in which it may play a role.

Respiratory Illness and Infection

Lack of sleep makes you more vulnerable to respiratory illness and infection. A study of more than 600,000 people found that insomnia was a contributing cause when catching a cold or the flu , as well as a factor in how severe the infection became.

Obstructive sleep apnea, a common sleep disturbance, is linked with a number of cardiovascular (heart and blood vessel) diseases. For example, 40% to 60% of people experiencing symptomatic heart failure also are diagnosed with sleep-disordered breathing.

Other heart conditions linked with sleep apnea include:

  • Coronary artery disease
  • Pulmonary hypertension
  • High blood pressure
  • Heart arrhythmias

There's no direct evidence to suggest that sleep quantity or quality affects the risk of cancer, although studies have looked at the role of sleep in developing breast cancer , lung cancer , and more.

For example, research on lung cancer suggests a relationship between lack of sleep and adenocarcinoma risk, but more research on sleep traits (how long you sleep, whether you take naps) is needed.

Studies also are exploring the role of sleep in those already diagnosed with cancer, especially because difficulty sleeping affects up to 95% of people receiving cancer treatment and care. Sleep deprivation may affect the body's ability to fight cancer and lead to a poor prognosis, which was the conclusion of researchers focused on liver cancer .

A number of studies have shown that sleep deprivation leads to reduced glucose tolerance and impaired insulin sensitivity in humans. Additional studies suggest the risk of type 2 diabetes rises due to inadequate sleep, with seven or eight hours considered the optimal amount.

Researchers also think the timing of sleep may have impacts, too. Disruptions in circadian rhythm, with many people working at night or otherwise "living against the clock" of natural sleep cycles, also have impacts. Sleep disruption appears to affect metabolism and related diseases.

Neurodegenerative Disease

Sleep plays a key role in how your body produces cerebrospinal fluid (CSF), what it's composed of, and how the CSF is distributed in your brain and spinal cord. A number of studies have looked at how components in CSF, like amyloid-beta levels, might be linked to Alzheimer's disease and other neurodegenerative disorders.

The research results are mixed, but there is evidence to suggest that sleep patterns affect levels of amyloid-beta, orexin, tau proteins, interleukin 8 (IL-8), and other components. This may influence the development of Lewy body dementia, Parkinson's, or Alzheimer's disease, or it may contribute to sleep disruptions that are common in people living with these disorders.

Researchers also are investigating the role of CSF, sleep, and the early development of autism .

Sleep Is Important for Your Mental Health

Evidence suggests lack of sleep contributes to the formation of new mental health problems and to the maintenance of existing ones, but the magnitude of its effect is difficult to estimate and may be different across mental health conditions.

Sleep problems are very common in those with mental illness. In fact, disrupted sleep is commonly seen as both a symptom and consequence of mental health disorders, although sleep deprivation is rarely treated as the cause of mental health conditions.

The most common sleep problem associated with poor mental health is insomnia, with symptoms of:

  • Not feeling well-rested after a night's sleep
  • Daytime tiredness or sleepiness
  • Irritability, depression, or anxiety
  • Difficulty paying attention, focusing on tasks, or remembering
  • Increased errors or accidents
  • Ongoing worries about sleep

You may experience insomnia for a number of reasons, but the most common culprits are: 

  • Work schedule
  • Poor sleep habits
  • Excessive alcohol or caffeine use at night 
  • Habitual nighttime screen use

Illustration by JR Bee for Verywell Health

Small changes to your nighttime routine can result in a huge health benefit:

  • Establish a realistic bedtime and stick to it every night, even on the weekends.
  • Maintain comfortable temperature settings and low light levels in your bedroom.
  • Consider a “screen ban” on televisions, computers and tablets, cell phones, and other electronic devices in your bedroom.
  • Abstain from caffeine, alcohol, and large meals in the hours leading up to bedtime.
  • Refrain from using tobacco at any time of day or night.
  • Exercise during the day; this can help you wind down in the evening and prepare for sleep.

Sleep is vital to maintaining health, and most adults need seven or more hours each day. There is increasing evidence that adequate, high-quality sleep can help prevent illnesses like respiratory infection as well as limit the risk of diabetes, heart disease, and other serious conditions.

Memory, mood, and mental health also are affected by sleep deprivation and other sleep disorders.

There are lifestyle steps you can take to improve sleep. Talk to your healthcare provider if you have concerns or questions about how sleep patterns are affecting your health.

Antza C, Kostopoulos G, Mostafa S, Nirantharakumar K, Tahrani A. The links between sleep duration, obesity and type 2 diabetes mellitus . J Endocrinol . 2021 Dec 13;252(2):125-141. doi:10.1530/JOE-21-0155.

Watson NF, Badr MS, Belenky G, Bliwise DL, Buxton OM, Buysse D, et al . Recommended Amount of Sleep for a Healthy Adult: A Joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society . Sleep . 2015 Jun 1;38(6):843-4. doi:10.5665/sleep.4716.

Chong PLH, Garic D, Shen MD, Lundgaard I, Schwichtenberg AJ. Sleep, cerebrospinal fluid, and the glymphatic system: A systematic review . Sleep Med Rev . 2022 Feb;61:101572. doi:10.1016/j.smrv.2021.101572. 

Walker WH 2nd, Walton JC, DeVries AC, Nelson RJ. Circadian rhythm disruption and mental health . Transl Psychiatry . 2020 Jan 23;10(1):28. doi:10.1038/s41398-020-0694-0. 

da Estrela C, McGrath J, Booij L, Gouin JP. Heart Rate Variability, Sleep Quality, and Depression in the Context of Chronic Stress . Ann Behav Med . 2021 Mar 16;55(2):155-164. doi:10.1093/abm/kaaa039.

Tucker MA, Humiston GB, Summer T, Wamsley E. Comparing the effects of sleep and rest on memory consolidation . Nature and Science of Sleep . 2020 Feb 3;12:79-91. doi:10.2147/NSS.S223917

Rasch B, Born J. About sleep’s role in memory .  Physiological Reviews . 2013;93(2):681-766. doi: 10.1152/physrev.00032.2012 

Chaput JP, McHill AW, Cox RC, Broussard JL, Dutil C, da Costa BGG, Sampasa-Kanyinga H, Wright KP Jr. The role of insufficient sleep and circadian misalignment in obesity . Nat Rev Endocrinol . 2023 Feb;19(2):82-97. doi:10.1038/s41574-022-00747-7.

Yeghiazarians Y, Jneid H, Tietjens JR, Redline S, Brown DL, El-Sherif N, et al . Obstructive Sleep Apnea and Cardiovascular Disease: A Scientific Statement From the American Heart Association . Circulation . 2021 Jul 20;144(3):e56-e67. doi:10.1161/CIR.0000000000000988.

Hanlon EC, Tasali E, Leproult R, Stuhr KL, Doncheck E, de Wit H, Hillard CJ, Van Cauter E.  Sleep restriction enhances the daily rhythm of circulating levels of endocannabinoid 2-arachidonoylglycerol . 2016 Mar 1;39(3):653-64. doi:10.5665/sleep.5546

Jones SE, Maisha FI, Strausz SJ, Lammi V, Cade BE, Tervi A, et al . The public health impact of poor sleep on severe COVID-19, influenza and upper respiratory infections . EBioMedicine . 2023 Jul;93:104630. doi:10.1016/j.ebiom.2023.104630

Wang J, Tang H, Duan Y, Yang S, An J. Association between Sleep Traits and Lung Cancer: A Mendelian Randomization Study . J Immunol Res . 2021 Jun 21;2021:1893882. doi:10.1155/2021/1893882. 

Büttner-Teleagă A, Kim YT, Osel T, Richter K. Sleep Disorders in Cancer-A Systematic Review . Int J Environ Res Public Health . 2021 Nov 7;18(21):11696. doi:10.3390/ijerph182111696.

Huang J, Song P, Hang K, Chen Z, Zhu Z, Zhang Y, et al . Sleep Deprivation Disturbs Immune Surveillance and Promotes the Progression of Hepatocellular Carcinoma . Front Immunol . 2021 Sep 3;12:727959. doi:10.3389/fimmu.2021.727959.

Parameswaran G, Ray DW. Sleep, circadian rhythms, and type 2 diabetes mellitus . Clin Endocrinol (Oxf) . 2022 Jan;96(1):12-20. doi:10.1111/cen.14607. 

Chasens ER, Imes CC, Kariuki JK, Luyster FS, Morris JL, DiNardo MM, et al . Sleep and Metabolic Syndrome . Nurs Clin North Am . 2021 Jun;56(2):203-217. doi:10.1016/j.cnur.2020.10.012.

Scott AJ, Webb TL, Rowse G. Does improving sleep lead to better mental health? A protocol for a meta-analytic review of randomised controlled trials . BMJ Open. 2017;7(9):e016873. Published 2017 Sep 18. doi:10.1136/bmjopen-2017-016873

By Shamard Charles, MD, MPH Shamard Charles, MD, MPH is a public health physician and journalist. He has held positions with major news networks like NBC reporting on health policy, public health initiatives, diversity in medicine, and new developments in health care research and medical treatments.

an essay on sleep

Why are we so sleep deprived, and why does it matter?

an essay on sleep

Vice chair, Department of Neurology, University of Florida

Disclosure statement

Michael S. Jaffee does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

University of Florida provides funding as a founding partner of The Conversation US.

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As we prepare to “spring forward” for daylight saving time, many of us dread the loss of the hour’s sleep we incur by moving our clocks forward. For millions, the loss will be an added insult to the inadequate sleep they experience on a daily basis.

Surveys show that 40 percent of American adults get less than the nightly minimum of seven hours of sleep recommended by the American Academy of Sleep Medicine and the National Sleep Foundation. The National Institutes for Health estimate that between 50 million and 70 million people do not get enough sleep. These recommendations for minimal sleep are based on a review of many scientific studies evaluating the role of sleep in our bodies and the effects of sleep deprivation on our ability of our body to function at our peak performance level.

I am a neurologist at the University of Florida who has studied the effects of both traumatic brain injury and sleep impairment on the brain. I have seen the effects of sleep impairment and the significant effects it can have.

According to the National Sleep Foundation, American adults currently average 6.9 hours of sleep per night compared with the 1940s, when most American adults were averaging 7.9 hours a night, or one hour more each night. In fact, in 1942, 84 percent of Americans got the recommended seven to nine hours; in 2013, that number had dropped to 59 percent . Participants in that same Gallup poll reported on average they felt they needed 7.3 hours of sleep each night but were not getting enough, causing an average nightly sleep debt of 24 minutes. Fitbit in January 2018 announced results of a study it conducted of 6 billion nights of its customers’ sleep and reported that men actually get even less than women, about 6.5 hours.

Why sleep matters

The problems caused by sleep shortage go beyond tiredness. In recent years, studies have shown that adults who were short sleepers, or those who got less than seven hours in 24 hours, were more likely to report 10 chronic health conditions , including heart disease, diabetes, obesity, asthma and depression, compared to those who got enough sleep, that is, seven or more hours in a 24-hour period.

There are more challenges for children, as they are thought to have an increased sleep need compared to adults. The American Academy of Sleep Medicine recommends that children 6 to 12 years of age should sleep nine to 12 hours a day and teens 13 to 18 should sleep eight to 10 hours daily on a regular basis to promote optimal health.

A Sleep Foundation poll of parents suggested that American children are getting one hour of sleep or more per night less than what their body and brain require.

Researchers have found that sleep deprivation of even a single hour can have a harmful effect on a child’s developing brain. Inadequate sleep can affect synaptic plasticity and memory encoding, and it can result in inattentiveness in the classroom.

Every one of our biological systems is affected by sleep. When we don’t sleep long enough or when we experience poor quality of sleep, there can be serious biological consequences.

When we are sleep deprived, our bodies become more aroused through an enhanced sympathetic nervous system , known as “fight or flight.” There is a greater propensity for increased blood pressure and possible risk of coronary heart disease. Our endocrine system releases more cortisol, a stress hormone. The body has less glucose tolerance and greater insulin resistance, which in the long term can cause an increased risk of Type 2 diabetes. Also, sleep deprivation causes a reduction in growth hormone and muscle maintenance.

We also rely on sleep to maintain our metabolism. Sleep deprivation can lead to decreased release of the hormone leptin and increased release of the hormone ghrelin, which can be associated with increased appetite and weight gain.

The human body also relies on sleep to help with our immune system. Sleep deprivation is associated with increased inflammation and decreased antibodies to influenza and decreased resistance to infection.

Inadequate sleep has been associated with a negative effect on mood as well as decreased attention and increased memory difficulty. In addition, someone who is sleep deprived may experience a decrease in pain tolerance and in reaction times. Occupational studies have associated sleep deprivation with decreased performance, increased car accidents, and more days missed from work.

The role of the brain

Researchers have known for a while that brain health is an important aspect of sleep. Notably, sleep is an important part of memory consolidation and learning.

Newer research has suggested another important aspect of sleep for our brain: There is a system for the elimination of possibly harmful proteins such as abnormal variants of amyloid. This waste removal process, using what is known as the glymphatic system , relies on sleep to effectively eliminate these proteins from the brain. These are the same proteins found to be elevated in patients with Alzheimer’s disease. Studies show that older adults with less sleep have greater accumulations of these proteins in their brains.

Our sleep-wake cycle is regulated by the circadian system , which helps signal the brain to sleep using the release of the natural hormone melatonin. It turns out that our body’s system for regulating melatonin and our sleep schedule is most powerfully controlled by light.

There are cells in the retina of our eye that communicate directly with the brain’s biological clock regulators located in the hypothalamus and this pathway is most affected by light. These neurons have been found to be most affected by light waves from the blue spectrum or blue light. This is the kind of light most prominent in electronic lights from computers and smartphones. This has become a modern challenge that can adversely affect our natural sleep-wake cycle.

Additional factors that can hamper sleep include pain conditions, medications for other conditions, and the increased demands and connectedness of modern society.

As we prepare for daylight saving time, we can be mindful that many athletes have been including planned sleep extensions (sleeping longer than usual) into their schedule to enhance performance and that many professional sports teams have hired sleep consultants to help assure their athletes have enough sleep. Perhaps we should have a similar game plan as we approach the second Sunday in March.

  • Sleep disorders
  • Sleep deprivation
  • Sleep apnea
  • Daylight saving time
  • Teens and sleep

an essay on sleep

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an essay on sleep

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an essay on sleep

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  • Why Is Sleep Important?
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MORE INFORMATION

How Sleep Works Why Is Sleep Important?

Language switcher.

Sleep plays a vital role in good health and well-being throughout your life. The way you feel while you are awake depends in part on what happens while you are sleeping. During sleep, your body is working to support healthy brain function and maintain your physical health.

In children and teens, sleep also helps support growth and development. Getting inadequate sleep over time can raise your risk for chronic (long-term) health problems. It can also affect how well you think, react, work, learn, and get along with others. Learn how sleep affects your heart and circulatory system, metabolism , respiratory system, and immune system and how much sleep is enough.

Sleep brochure cover image

This brochure describes the differences between the types of sleep needed to feel awake and to be healthy and offers tips for getting a good night’s sleep.

Heart and circulatory system

When you fall asleep and enter non-REM sleep , your blood pressure and heart rate fall. During sleep, your parasympathetic system controls your body, and your heart does not work as hard as it does when you are awake. During REM sleep and when waking, your sympathetic system is activated, increasing your heart rate and blood pressure to the usual levels when you are awake and relaxed. A sharp increase in blood pressure and heart rate upon waking has been linked to angina, or chest pain, and heart attacks .

People who do not sleep enough or wake up often during the night may have a higher risk of:

  • Coronary heart disease
  • High blood pressure

Hormones and sleep

Your body makes different hormones at different times of day. This may be related to your sleep pattern or your circadian clocks. In the morning, your body releases hormones that promote alertness, such as cortisol, which helps you wake up. Other hormones have 24-hour patterns that vary throughout your life; for example, in children, the hormones that tell the glands to release testosterone, estrogen, and progesterone are made in pulses at night, and the pulses get bigger as puberty approaches.

Metabolism and sleep

The way your body handles fat varies according to various circadian clocks, including those in the liver, fat, and muscle. For example, the circadian clocks make sure that your liver is prepared to help digest fats at appropriate times. Your body may handle fat differently if you eat at unusual times.

Studies have shown that not getting enough quality sleep can lead to:

  • Higher levels of the hormones that control hunger, including leptin and ghrelin, inside your body
  • Decreased ability to respond to insulin
  • Increased consumption of food, especially fatty, sweet, and salty foods
  • Decreased physical activity
  • Metabolic syndrome

All of these contribute to overweight and obesity .

Respiratory and immune systems

During sleep, you breathe less often and less deeply and take in less oxygen. These changes can cause problems in people who have health problems such as asthma or chronic obstructive pulmonary disease (COPD) . Asthma symptoms are usually worse during early morning sleep. Likewise, breathing problems in people who have lung diseases such as COPD can become worse during sleep.

Sleep also affects different parts of your immune system, which become more active at different times of day. For example, when you sleep, a particular type of immune cell works harder. That is why people who do not sleep enough may be more likely to get colds and other infections.

Lung Health Basics: Sleep Fact Sheet

Lung Health Basics: Sleep

People with lung disease often have  trouble sleeping. Sleep is critical to overall health, so take the first step to sleeping better: learn these sleep terms, and find out about treatments that can help with sleep apnea.

Problems with thinking and memory

Sleep helps with learning and the formation of long-term memories. Not getting enough sleep or enough high-quality sleep can lead to problems focusing on tasks and thinking clearly. Read our Sleep Deprivation and Deficiency page for more information on how lack of sleep affects performance of daily activities, including driving and schoolwork.

4.2 Sleep and Why We Sleep

Learning objectives.

By the end of this section, you will be able to:

  • Describe areas of the brain involved in sleep
  • Understand hormone secretions associated with sleep
  • Describe several theories aimed at explaining the function of sleep
  • Name and describe three theories about why we dream

We spend approximately one-third of our lives sleeping. Given the average life expectancy for U.S. citizens falls between 73 and 79 years old (Singh & Siahpush, 2006), we can expect to spend approximately 25 years of our lives sleeping. Some animals never sleep (e.g., some fish and amphibian species); other animals sleep very little without apparent negative consequences (e.g., giraffes); yet some animals (e.g., rats) die after two weeks of sleep deprivation (Siegel, 2008). Why do we devote so much time to sleeping? Is it absolutely essential that we sleep? This section will consider these questions and explore various explanations for why we sleep.

What is Sleep?

You have read that sleep is distinguished by low levels of physical activity and reduced sensory awareness. As discussed by Siegel (2008), a definition of sleep must also include mention of the interplay of the circadian and homeostatic mechanisms that regulate sleep. Homeostatic regulation of sleep is evidenced by sleep rebound following sleep deprivation. Sleep rebound refers to the fact that a sleep-deprived individual will fall asleep more quickly during subsequent opportunities for sleep. Sleep is characterized by certain patterns of activity of the brain that can be visualized using electroencephalography (EEG), and different phases of sleep can be differentiated using EEG as well.

Sleep-wake cycles seem to be controlled by multiple brain areas acting in conjunction with one another. Some of these areas include the thalamus, the hypothalamus, and the pons. As already mentioned, the hypothalamus contains the SCN—the biological clock of the body—in addition to other nuclei that, in conjunction with the thalamus, regulate slow-wave sleep. The pons is important for regulating rapid eye movement (REM) sleep (National Institutes of Health, n.d.).

Sleep is also associated with the secretion and regulation of a number of hormones from several endocrine glands including: melatonin, follicle stimulating hormone (FSH), luteinizing hormone (LH), and growth hormone (National Institutes of Health, n.d.). You have read that the pineal gland releases melatonin during sleep ( Figure 4.6 ). Melatonin is thought to be involved in the regulation of various biological rhythms and the immune system (Hardeland et al., 2006). During sleep, the pituitary gland secretes both FSH and LH which are important in regulating the reproductive system (Christensen et al., 2012; Sofikitis et al., 2008). The pituitary gland also secretes growth hormone, during sleep, which plays a role in physical growth and maturation as well as other metabolic processes (Bartke, Sun, & Longo, 2013).

Why Do We Sleep?

Given the central role that sleep plays in our lives and the number of adverse consequences that have been associated with sleep deprivation, one would think that we would have a clear understanding of why it is that we sleep. Unfortunately, this is not the case; however, several hypotheses have been proposed to explain the function of sleep.

Adaptive Function of Sleep

One popular hypothesis of sleep incorporates the perspective of evolutionary psychology. Evolutionary psychology is a discipline that studies how universal patterns of behavior and cognitive processes have evolved over time as a result of natural selection . Variations and adaptations in cognition and behavior make individuals more or less successful in reproducing and passing their genes to their offspring. One hypothesis from this perspective might argue that sleep is essential to restore resources that are expended during the day. Just as bears hibernate in the winter when resources are scarce, perhaps people sleep at night to reduce their energy expenditures. While this is an intuitive explanation of sleep, there is little research that supports this explanation. In fact, it has been suggested that there is no reason to think that energetic demands could not be addressed with periods of rest and inactivity (Frank, 2006; Rial et al., 2007), and some research has actually found a negative correlation between energetic demands and the amount of time spent sleeping (Capellini, Barton, McNamara, Preston, & Nunn, 2008).

Another evolutionary hypothesis of sleep holds that our sleep patterns evolved as an adaptive response to predatory risks, which increase in darkness. Thus we sleep in safe areas to reduce the chance of harm. Again, this is an intuitive and appealing explanation for why we sleep. Perhaps our ancestors spent extended periods of time asleep to reduce attention to themselves from potential predators. Comparative research indicates, however, that the relationship that exists between predatory risk and sleep is very complex and equivocal. Some research suggests that species that face higher predatory risks sleep fewer hours than other species (Capellini et al., 2008), while other researchers suggest there is no relationship between the amount of time a given species spends in deep sleep and its predation risk (Lesku, Roth, Amlaner, & Lima, 2006).

It is quite possible that sleep serves no single universally adaptive function, and different species have evolved different patterns of sleep in response to their unique evolutionary pressures. While we have discussed the negative outcomes associated with sleep deprivation, it should be pointed out that there are many benefits that are associated with adequate amounts of sleep. A few such benefits listed by the National Sleep Foundation (n.d.) include maintaining health, lowering stress levels, improving mood, and increasing motor coordination, as well as a number of benefits related to cognition and memory formation.

Cognitive Function of Sleep

Another theory regarding why we sleep involves sleep’s importance for cognitive function and memory formation (Rattenborg, Lesku, Martinez-Gonzalez, & Lima, 2007). Indeed, we know sleep deprivation results in disruptions in cognition and memory deficits (Brown, 2012), leading to impairments in our abilities to maintain attention, make decisions, and recall long-term memories. Moreover, these impairments become more severe as the amount of sleep deprivation increases (Alhola & Polo-Kantola, 2007). Furthermore, slow-wave sleep after learning a new task can improve resultant performance on that task (Huber, Ghilardi, Massimini, & Tononi, 2004) and seems essential for effective memory formation (Stickgold, 2005). Understanding the impact of sleep on cognitive function should help you understand that cramming all night for a test may not be effective and can even prove counterproductive.

Link to Learning

Watch this brief video that gives sleep tips for college students to learn more.

Getting the optimal amount of sleep has also been associated with other cognitive benefits. Research indicates that included among these possible benefits are increased capacities for creative thinking (Cai, Mednick, Harrison, Kanady, & Mednick, 2009; Wagner, Gais, Haider, Verleger, & Born, 2004), language learning (Fenn, Nusbaum, & Margoliash, 2003; Gómez, Bootzin, & Nadel, 2006), and inferential judgments (Ellenbogen, Hu, Payne, Titone, & Walker, 2007). It is possible that even the processing of emotional information is influenced by certain aspects of sleep (Walker, 2009).

Watch this brief video about the relationship between sleep and memory to learn more.

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Why Is Sleep Important?

Reviewed by Psychology Today Staff

Sleep is the balm that soothes and restores after a long day. Sleep is largely driven by the body’s internal clock, which takes cues from external elements such as sunlight and temperature. The body’s natural sleep-and-wake cycle is reasonably attuned to a 24-hour period.

Perturbations in the sleep cycle are disruptive to the functioning of many body systems. Learning, memory , stamina, general health, and mood are all affected by sleep duration and quality. For many people, sleep is elusive or otherwise troubled. In fact, most people, at some point in their lives, experience difficulty falling asleep or staying asleep. Potential consequences of consistently poor sleep include obesity, cardiovascular disease, and diabetes. Sleep deprivation can also affect judgement and mental acuity.

Sleep needs differ from person to person and across different age groups. One person may need eight full hours, while another can function with less sleep. The good news is that the treatment of sleep disorders is rapidly progressing.

On This Page

  • Why do we sleep?
  • How much sleep do I need?
  • How long should it take me to fall asleep?
  • Do some people need more sleep than others?
  • Am I a “short sleeper”?
  • How can I get better sleep?
  • What is the purpose of dreams?
  • What is a chronotype?
  • How do I find out my chronotype?
  • What is “sleep debt”?
  • Should I replace my mattress?
  • Can weighted blankets and other tools help me sleep?

 pathdoc/ Shutterstock

Despite the universal need for sleep, there remains much about it that scientists don’t understand. It is known that sleep allows for the body and brain to replenish energy and repair themselves in critical ways. Memory consolidation, information processing, physical growth, muscle repair, and countless other processes are theorized to occur during sleep; sleep is also critical for strengthening the immune system and allowing the body to fight off disease.

To learn more about the benefits of sleep, see Sleep and Mental Health or Sleep and Physical Health.

an essay on sleep

Sleep needs vary by age, and variation exists even within age groups. But in general, The National Sleep Foundation provides these daily sleep guidelines:

  • Infants (4-11 months): 12-15 hours
  • School-age children (6-13): 9-11 hours
  • Teenagers (14-17): 8-10 hours
  • Young adults (18-25): 7-9 hours
  • Adults (26-64): 7-9 hours
  • Older adults (65+): 7-8 hours

To learn more about how sleep needs change over time, see Children and Sleep.

Nevada31/ Shutterstock

In general, it should take about 10 to 20 minutes for a person to drift off. But if one perceives that it is taking too long—whether it takes 20 minutes or an hour—that can spur anxiety about sleep that negatively affects sleep quality. Falling asleep as soon as one's head hits the pillow is not proof that one is a good sleeper; it's more likely an indication that an individual is sleep-deprived.

For more on recognizing signs of disordered sleep, see Overcoming Insomnia or Sleep Disorders.

an essay on sleep

Absolutely. Some people may feel great after 7 hours of sleep, while others don’t feel rested unless they get a solid 9. There do appear to be rare individuals who can function on significantly less sleep, which evidence suggests is due to genetics ; conversely, there appear to be some people who require significantly longer amounts of sleep—up to 10 hours a night—to function optimally.

YesPhotographers/ Shutterstock

“Short sleepers”—or those who are genetically programmed to require less sleep than average—do exist, and are thought to make up approximately 5 percent of the population . However, many people who think they are functioning well on little sleep may actually be chronically sleep deprived , as evidence suggests that it becomes difficult for people to objectively judge their mental state after several nights of poor sleep.

Chinnapong/ Shutterstock

The standard sleep hygiene advice can be of great help to many poor sleepers: Make sure your bedroom is cool and dark. Use your bed only for sex and sleep. Avoid caffeine from mid-afternoon on. And avoid all screens for at least an hour before turning in; screens' melatonin-inhibiting blue light delays sleep latency by an average of 10 minutes. Falling asleep in front of a TV, as 61 percent of adults confess to having done, is a problem as well: The screen's light penetrates the eyelids, so the brain still experiences exposure to light. This phenomenon prevents the more refreshing stages of deep sleep.

For more on improving sleep, see How to Sleep Better.

an essay on sleep

Researchers still aren’t entirely sure, but theories abound. Some experts hypothesize that dreams and nightmares—which often consist, at least in part, of real people, places, and life events—help the brain consolidate memories accumulated over the course of the day, identifying which ones to retain for long-term memory and allowing the rest to fade. Others argue that dream scenarios allow us to process emotions, mull over problems, or act out fantasies in a safe environment. Regardless of their purpose, what is known about dreams is that they appear to be universal—even if some people almost never remember having them.

For more about dreams, see Understanding Dreams or Managing Nightmares.

kanyanat wongsa/ Shutterstock

The word “chronotype” refers to an individual’s preferred sleep/wake schedule, based on their biologically programmed circadian rhythm . The most well-known chronotypes are “night owls”—or those who prefer to stay up late into the evening and awaken later in the day—and “morning larks,” who lean toward an “early to bed, early to rise” schedule. Chronotypes exist on a spectrum; while a few people are at either extreme, the majority of people fall somewhere in the middle.

kanyanat wongsa/ Shutterstock

Most people discover their chronotype by a process of trial and error; they naturally gravitate toward a specific sleep schedule and feel “off” when that schedule is interrupted. For those who are unsure, there also exist online quizzes that purport to help individuals understand their chronotype.

an essay on sleep

The term “sleep debt” refers to the difference between the amount of sleep someone needs and the amount of sleep they actually get; someone whose body requires 8 hours of sleep per night, for instance, but only gets 6, would accumulate a 14-hour sleep debt over the course of a week. Accumulating a large sleep debt has been associated with increased risk of certain physical and mental health conditions such as diabetes or anxiety.

For more on tackling insufficient sleep, see Overcoming Insomnia.

New Africa/ Shutterstock

An old or poor-quality mattress may be hindering sleep quality. The Better Sleep Council states that mattresses should be replaced every 7 to 10 years; older ones tend to stop providing adequate support, resulting in restless, inadequate sleep; they also accumulate allergens which can further disrupt sleep.

 fizkes/ Shutterstock

Many sleep experts endorse the use of weighted blankets, and not just for those with conditions like restless leg syndrome. Users find that the blankets provide the same type of comfort as hugs or swaddling for babies. Wearing a sleep-tracking bracelet that can record when one falls asleep and wakes up, and detect interrupted sleep, can also help some people. Ironically, its primary benefit may be providing reassurance to those who believe they’re getting hardly any sleep—a phenomenon known as paradoxical insomnia .

an essay on sleep

Falling and staying asleep gets harder when we're exposed to more light, drink more, can't cool down, and suffer allergies. Here's how to mitigate these seasonal factors.

an essay on sleep

There is no doubt that people have needs. Needs matter. An unmet need will demand your attention. Needs definitely need to be met, but no one can do that meeting for you.

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Lack of sleep can cause a range of problems from impaired coordination to mood swings. Yet, sometimes it is unavoidable. Here's how to cope after a sleepless night.

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The most powerful model for the future of dream interpretation will be a human-AI hybrid approach.

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A Personal Perspective: A daily rest time is like having a small vacation by a lake every day.

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Discover the transformative power of deep rest in combating stress and unlocking vitality. Explore how simple practices like meditation and yoga can rejuvenate the mind and body.

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You will discover how getting stuck in a dream can promote movement in life.

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How often are sleep disorders undiagnosed, under-treated, or mistreated?

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Have you been having strange dreams lately? Here's what they might mean.

an essay on sleep

Do you have insomnia or sleep disturbances? You are not alone. CBT-I is a promising treatment for insomnia without the aid of sleep medication.

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At any moment, someone’s aggravating behavior or our own bad luck can set us off on an emotional spiral that threatens to derail our entire day. Here’s how we can face our triggers with less reactivity so that we can get on with our lives.

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Sleep Loss and Emotion: A Systematic Review and Meta-Analysis

Saul Mcleod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul Mcleod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

Learn about our Editorial Process

Olivia Guy-Evans, MSc

Associate Editor for Simply Psychology

BSc (Hons) Psychology, MSc Psychology of Education

Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.

Sleep and emotion are fundamentally intertwined, both being universal human experiences that profoundly shape our daily functioning and well-being. Our emotional states influence every facet of our lives, from our physical health and cognitive performance to our social relationships and overall life satisfaction. Similarly, sleep plays a vital role in regulating our emotional processing , reactivity, and mood.

A sad woman in bed holding her head with tangled lines representing thought surrounding her head.

  • This meta-analysis synthesized over 50 years of experimental research on sleep loss and emotion, examining the effects of sleep deprivation, sleep restriction, and sleep fragmentation on various emotional outcomes.
  • Sleep loss resulted in reduced positive affect (SMD = -0.27 to -1.14), increased anxiety symptoms (SMD = 0.57-0.63), and blunted arousal in response to emotional stimuli (SMD = -0.20 to -0.53). Findings for negative affect, emotional valence, and depressive symptoms varied based on the type of sleep loss.
  • Nonlinear dose-response effects were found for the amount of sleep loss on some emotional outcomes. Losing REM sleep had a stronger effect on unpleasant emotional reactivity compared to losing slow-wave sleep.
  • While the research sheds light on the detrimental effects of sleep loss on emotions, it has some limitations such as relying predominantly on young adult samples and potential expectancy effects.
  • The pervasiveness of insufficient sleep worldwide makes this an important public health issue with significant implications for emotional well-being and risk for psychiatric disorders.

Sleep loss is common in modern society, with large segments of the population regularly failing to obtain adequate sleep (Hafner et al., 2017).

Poor sleep is known to catalyze the development of emotional difficulties and affective disorders across the lifespan (Goldstein & Walker, 2014; Gregory et al., 2009).

While an increasing number of experimental studies have demonstrated the adverse effects of sleep loss on emotion in recent decades (Palmer & Alfano, 2017; Tempesta et al., 2018), findings have been mixed and a comprehensive quantitative synthesis was needed to integrate results across the heterogeneous research designs and consolidate conclusions.

This meta-analysis aimed to quantify the effects of various forms of experimental sleep loss (deprivation, restriction, fragmentation) on multiple aspects of emotional experience and elucidate factors that may influence these effects.

The researchers conducted a preregistered systematic review and meta-analysis following PRISMA guidelines.

They searched PubMed/MEDLINE, PsychINFO, and Web of Science databases for experimental studies examining the effects of sleep deprivation, sleep restriction, or sleep fragmentation on positive affect, negative affect, mood disturbance, emotional reactivity, anxiety symptoms and/or depressive symptoms in healthy populations.

Additional unpublished data was sought via listservs and contacting authors. Inclusion criteria required studies to have healthy samples, an experimental sleep loss manipulation, an adequate control/baseline condition, and an emotion-related dependent variable.

Two independent coders screened and extracted data from eligible studies.

Search strategy and terms

The search criteria included human studies mentioning experimental sleep manipulations and any emotion-related outcomes in the title/abstract. There were no restrictions on language, location or date.

Inclusion and exclusion criteria

Included studies had to 1) use healthy samples without psychiatric, sleep or medical disorders that impact sleep/emotions, 2) experimentally manipulate nighttime sleep deprivation, restriction or fragmentation, 3) have an adequate control/baseline condition, 4) assess an emotion-related dependent variable after the sleep manipulation.

Studies were excluded if they used specialized samples, nap/circadian protocols, or had an intervention prior to the emotional assessment that could affect outcomes.

Statistical measures

Standardized mean differences (Hedges’ g) were calculated for each eligible outcome. Multivariate multilevel random effects models were used to estimate overall effects for each sleep loss type and emotional outcome, accounting for non-independent effect sizes.

Mixed effects models examined potential moderators. Heterogeneity, outliers, and indices of publication bias were assessed.

The meta-analysis included 154 studies (N=5,717) yielding 1,338 effect sizes.

For sleep deprivation (k=599), significant effects were found for reduced positive affect (SMD=-0.86), increased negative affect (SMD=0.37), mood disturbance (SMD=0.71), blunted arousal (SMD=-0.53), and anxiety (SMD=0.63). Nonlinear dose-response effects showed negative affect, mood disturbance and anxiety peaking at 30-60 hours of wakefulness.

For sleep restriction (k=483), effects were significant for reduced positive affect (SMD=-0.56), increased negative affect (SMD=0.20), mood disturbance (SMD=0.56), greater unpleasantness (SMD=0.23), blunted arousal (SMD=-0.20), anxiety (SMD=0.57) and depression (SMD=0.46). Nonlinear dose-response effects found the largest deficits for positive affect and unpleasantness around 4 hours of sleep.

Sleep fragmentation (k=256) significantly reduced positive affect (SMD=-0.40) and blunted arousal (SMD=-0.36). There were no significant effects on negative affect, mood, or valence.

Some moderating effects of age, sex, and study characteristics emerged, though not consistently across outcomes. Importantly, losing REM sleep had a stronger effect than losing slow-wave sleep on ratings of unpleasantness to emotional stimuli.

This meta-analysis provides the most comprehensive picture to date of how sleep loss impacts human emotions.

It demonstrates that multiple aspects of emotional functioning are significantly altered by sleep deprivation, restriction, and fragmentation.

The most robust effects across all three types of sleep loss were found for reductions in positive affect, suggesting that inadequate sleep may be particularly detrimental for experiences and expressions of positive emotions.

This could have important mental health implications given the role of positive emotionality in psychological well-being and resilience (Fredrickson, 2001). The blunting of emotional arousal also seen after sleep loss may reflect impairments in top-down emotional processing.

In contrast, sleep loss effects on negative affect were smaller and less consistent across studies. The evolutionary importance of negative emotions for signaling threats and promoting survival could make negative affective responses more resistant to the effects of sleep loss compared to positive affect.

However, anxiety symptoms were consistently increased by sleep loss, indicating heightened feelings of apprehension and worry. The dose-response findings suggest these detrimental effects on negative affect and anxiety are exacerbated by more extreme sleep deprivation.

An intriguing finding was that losing REM sleep impacted ratings of emotional stimuli more than losing slow-wave sleep. This aligns with theories proposing a key role of REM sleep in emotional memory consolidation and maintaining emotional reactivity (Walker & van der Helm, 2009).

More targeted research comparing the effects of selective REM and slow-wave sleep deprivation on emotional reactivity and regulation is needed.

While only a small number of studies included children or older adults, some moderating effects of age did emerge, with sleep loss having stronger effects on mood disturbances in older individuals. Examining sleep-emotion dynamics in developmental and lifespan contexts is an important future direction.

Sex differences were also found for some outcomes, but not consistently, highlighting the need for more studies powered to detect potential gender differences in emotional vulnerability to sleep loss.

Overall, these findings underscore the consequences of insufficient sleep for affective experience and functioning. They provide an important foundation for further investigating the mechanisms linking sleep and emotion and developing interventions to mitigate the risks of sleep loss for emotional health.

  • Preregistration of the study design and analytical plan
  • Adherence to PRISMA guidelines for transparent reporting
  • Comprehensive search strategy across multiple databases
  • Inclusion of unpublished data to mitigate publication bias
  • Rigorous coding procedures with two independent coders
  • Examination of multiple types of sleep loss and emotional outcomes
  • Advanced statistical methods accounting for non-independent effect sizes
  • Assessment of heterogeneity, outliers, and publication bias indices

Limitations

  • Most studies used young adult samples, limiting generalizability to other ages
  • There was a lack of geographical diversity, with studies predominantly from Western countries
  • Masking participants to sleep loss conditions is not possible, so expectancy effects may have influenced results
  • Some analyses for specific emotional outcomes or sleep types had a small number of studies
  • Variability in emotional assessments and sleep manipulation procedures across studies

Implications

The finding that even relatively modest amounts of sleep loss can have significant negative repercussions for emotional well-being has important real-world implications.

With up to one-third of the general adult population reporting insufficient sleep (Liu et al., 2016), a substantial proportion of people may be at heightened risk for emotional difficulties and affective disorders as a result of inadequate sleep.

This makes sleep a critical target for public health interventions aimed at promoting mental health.

The differential impacts of REM versus slow-wave sleep loss on emotional reactivity also have clinical relevance, suggesting sleep stage-specific interventions may be warranted for certain emotional issues.

The nonlinear dose-response effects for several outcomes indicate that sleeping less than 4-5 hours and/or being continuously awake for over 24 hours may represent particularly dangerous thresholds for emotional health.

Organizations and occupations where sleep loss is common (e.g., military, healthcare, shift work) need to be aware of the risks to emotional well-being and implement strategies to mitigate these effects.

Public policies regulating work hours and school start times should prioritize sleep to reduce adverse emotional consequences at the population level.

With the high rates of insufficient sleep among adolescents (Basch et al., 2014) and emerging mood disorders during this developmental period, optimizing sleep could be an important avenue for youth mental health promotion.

More broadly, initiatives to increase public awareness about the importance of sleep for emotional health, address barriers to adequate sleep, and promote evidence-based sleep hygiene practices have the potential to make a substantial and much-needed impact on psychological well-being and public health.

The current findings underscore the affective benefits of prioritizing sleep and the dangers of sacrificing it.

Primary reference

Palmer, C. A., Bower, J. L., Cho, K. W., Clementi, M. A., Lau, S., Oosterhoff, B., & Alfano, C. A. (2024). Sleep loss and emotion: A systematic review and meta-analysis of over 50 years of experimental research. Psychological Bulletin, 150 (4), 440–463. https://doi.org/10.1037/bul0000410

Other references

Basch, C. E., Basch, C. H., Ruggles, K. V., & Rajan, S. (2014). Prevalence of sleep duration on an average school night among 4 nationally representative successive samples of American high school students, 2007–2013. Preventing Chronic Disease, 11 , Article 140383. https://doi.org/10.5888/pcd11.140383

Fredrickson, B. L. (2001). The role of positive emotions in positive psychology. The broaden-and-build theory of positive emotions. American Psychologist, 56 (3), 218–226. https://doi.org/10.1037/0003-066X.56.3.218

Goldstein, A. N., & Walker, M. P. (2014). The role of sleep in emotional brain function. Annual Review of Clinical Psychology, 10, 679-708. https://doi.org/10.1146/annurev-clinpsy-032813-153716

Gregory, A. M., Rijsdijk, F. V., Lau, J. Y., Dahl, R. E., & Eley, T. C. (2009). The direction of longitudinal associations between sleep problems and depression symptoms: a study of twins aged 8 and 10 years. Sleep, 32 (2), 189-199. https://doi.org/10.1093/sleep/32.2.189

Hafner, M., Stepanek, M., Taylor, J., Troxel, W. M., & van Stolk, C. (2017). Why sleep matters—the economic costs of insufficient sleep: a cross-country comparative analysis. Rand Health Quarterly, 6 (4), 11. https://doi.org/10.7249/RB9962

Liu, Y., Wheaton, A. G., Chapman, D. P., Cunningham, T. J., Lu, H., & Croft, J. B. (2016). Prevalence of healthy sleep duration among adults — United States, 2014. MMWR. Morbidity and Mortality Weekly Report, 65 (6), 137–141. https://doi.org/10.15585/mmwr.mm6506a1

Palmer, C. A., & Alfano, C. A. (2017). Sleep and emotion regulation: An organizing, integrative review. Sleep Medicine Reviews, 31, 6-16. https://doi.org/10.1016/j.smrv.2015.12.006

Tempesta, D., Socci, V., De Gennaro, L., & Ferrara, M. (2018). Sleep and emotional processing. Sleep Medicine Reviews, 40, 183-195. https://doi.org/10.1016/j.smrv.2017.12.005

Walker, M. P., & van der Helm, E. (2009). Overnight therapy? The role of sleep in emotional brain processing. Psychological Bulletin, 135 (5), 731–748. https://doi.org/10.1037/a0016570

Keep Learning

  • How does this meta-analysis advance our understanding of the relationship between sleep and emotion compared to previous individual studies? What are the advantages of synthesizing results across multiple studies?
  • The strongest effects of sleep loss were found for positive affect. Why might inadequate sleep be particularly detrimental for positive emotions from an evolutionary or neurobiological perspective? What are the potential mental health implications of this finding?
  • The study found some moderating effects of age on the sleep loss-emotion relationship. How might the effects of sleep loss on emotional functioning differ across the lifespan from childhood to older adulthood? What developmental factors could influence this?
  • Losing REM sleep impacted emotional reactivity to unpleasant stimuli more than losing slow-wave sleep. What are the potential mechanisms that could explain this finding? How does it relate to theories about the role of REM sleep in emotional memory processing?
  • Given the pervasiveness of insufficient sleep in the population, what public health strategies or policies could help mitigate the negative emotional consequences of sleep loss at a societal level? How could this research inform interventions for at-risk groups?
  • What are some of the limitations of experimental sleep research for understanding real-world emotional functioning? How well do these controlled laboratory studies generalize to chronic partial sleep loss as it’s experienced in daily life?
  • Where should sleep and emotion research go from here? What are the most pressing unanswered questions or promising future directions based on the current state of the science? What types of studies or methodologies are needed to advance the field?

An infographic titled 'Coping with sleep deprivation' followed by 8 tips and illustrations for coping e.g., establishing a night-time routine and limiting caffeine.

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Essay on Importance of Sleep

Students are often asked to write an essay on Importance of Sleep in their schools and colleges. And if you’re also looking for the same, we have created 100-word, 250-word, and 500-word essays on the topic.

Let’s take a look…

100 Words Essay on Importance of Sleep

Understanding sleep.

Sleep is a crucial part of our lives. It helps us rest, rejuvenate, and prepare for the next day. Without sleep, our bodies and minds cannot function properly.

Why is Sleep Important?

Sleep contributes to our overall health. It allows our brain to process information and memories. It also gives our body time to repair and grow.

Effects of Lack of Sleep

Lack of sleep can lead to health issues like heart disease and obesity. It also affects our mood, making us feel irritable and stressed.

So, quality sleep is essential for our well-being. Make sleep a priority to stay healthy and happy.

250 Words Essay on Importance of Sleep

The necessity of sleep.

Sleep, often overlooked in our fast-paced society, is a fundamental aspect of human health and well-being. Its importance extends beyond merely banishing under-eye circles or boosting mood; it is an essential part of our biological function.

Role in Physical Health

Sleep plays a significant role in the body’s healing and repair processes, particularly for the heart and blood vessels. Chronic sleep deficiency is linked to heart disease, kidney disease, high blood pressure, diabetes, and stroke. Furthermore, it aids in maintaining a healthy balance of hormones that regulate feelings of hunger and satiety, thereby indirectly influencing our body weight and food choices.

Cognitive Function and Emotional Well-being

Sleep is vital for various aspects of brain function. This includes cognition, concentration, productivity, and performance. During sleep, your brain forms new pathways to help you learn and remember information. A good night’s sleep improves problem-solving skills and enhances memory. Lack of sleep impairs these functions, leading to decreased productivity and increased mistakes.

The Impact on Mental Health

Sleep deficiency has been linked to an increased risk of developing mental health disorders, including depression, anxiety, and mood swings. Sleep helps reset our emotional brain circuits, allowing us to manage daily stress and adapt to change.

In conclusion, sleep is not a luxury, but a necessity. It’s a vital part of our lives that impacts our physical health, cognitive function, emotional well-being, and overall quality of life. Recognizing the importance of sleep and making necessary adjustments to prioritize it is a crucial step towards improved health and productivity.

500 Words Essay on Importance of Sleep

The importance of sleep: an underrated aspect of health.

Sleep, often overlooked, is a crucial aspect of our overall health and well-being. In our fast-paced society, sleep is frequently sacrificed for more seemingly productive activities, however, this neglect can have serious health consequences.

The Science of Sleep

Sleep is not merely a passive state where the body is at rest. It is a complex physiological process where essential activities occur. During sleep, the body undergoes repair and rejuvenation, and the brain processes and integrates information gathered throughout the day. Sleep is divided into two distinct types: Rapid Eye Movement (REM) sleep and Non-Rapid Eye Movement (NREM) sleep. Each stage has specific functions, with NREM sleep primarily involved in physical restoration and REM sleep associated with memory consolidation and brain development.

The Health Implications of Sleep Deprivation

Chronic sleep deprivation can lead to a host of health problems. Physically, it can increase the risk of conditions such as obesity, diabetes, and cardiovascular disease. It weakens the immune system, making one more susceptible to infections. Neurologically, lack of sleep can impair cognition, memory, and mood. Studies have shown that sleep deprivation can lead to decreased concentration, memory lapses, loss of creativity, and mood swings. Furthermore, chronic sleep deprivation has been linked to mental health disorders such as depression and anxiety.

Sleep and Academic Performance

For college students, sleep is especially important. Numerous studies have demonstrated a correlation between sleep and academic performance. Adequate sleep can enhance learning and memory, improve concentration, and boost creativity, all of which are crucial for academic success. Conversely, sleep deprivation can impede these cognitive functions, leading to decreased academic performance.

Improving Sleep Quality

Given the importance of sleep, it is essential to prioritize it and adopt good sleep hygiene practices. These include maintaining a regular sleep schedule, creating a sleep-friendly environment, avoiding stimulating activities before bedtime, and addressing any underlying sleep disorders.

In conclusion, sleep is a crucial aspect of health that is often undervalued. The implications of sleep deprivation are far-reaching, affecting physical health, mental health, and cognitive functions. As college students, it is essential to prioritize sleep to maintain overall health and optimize academic performance. By understanding the importance of sleep and adopting good sleep hygiene practices, we can reap the benefits of this vital physiological process.

That’s it! I hope the essay helped you.

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an essay on sleep

Theses on Sleep

Summary: In this essay, I question some of the consensus beliefs about sleep, such as the need for at least 7 hours of sleep for adults, harmfulness of acute sleep deprivation, and harmfulness of long-term sleep deprivation and our inability to adapt to it.

It appears that the evidence for all of these beliefs is much weaker than sleep scientists and public health experts want us to believe. In particular, I conclude that it’s plausible that at least acute sleep deprivation is not only not harmful but beneficial in some contexts and that it’s that we are able to adapt to long-term sleep deprivation.

I also discuss the bidirectional relationship of sleep and mania/depression and the costs of unnecessary sleep, noting that sleeping 1.5 hours per day less results in gaining more than a month of wakefulness per year, every year.

Note: I sleep the normal 7-9 hours if I don’t restrict my sleep. However, stimulants like coffee, modafinil, and adderall seem to have much smaller effect on my cognition than on cognition of most people I know. My brain in general, as you might guess from reading this site , is not very normal. So, be cautious before trying anything with your sleep on the basis of the arguments I lay out below. Specifically do not make any drastic changes to your sleep schedule on the basis of reading this essay and, if you want to experiment with sleep, do it gradually (i.e. varying the average amount of sleep by no more than 30 minutes at a time) and carefully.

Also see Natália Coelho Mendonça Counter-theses on Sleep .

Comfortable modern sleep is an unnatural superstimulus. Sleepiness, just like hunger, is normal.

The default argument for sleeping 7-9 hours a night is that this is the amount of sleep most of us get “naturally” when we sleep without using alarms. In this section, I argue against this line of reasoning, using the following analogy:

  • Experiencing hunger is normal and does not necessarily imply that you are not eating enough. Never being hungry means you are probably eating too much.
  • Experiencing sleepiness is normal and does not necessarily imply that you are undersleeping. Never being sleepy means you are probably sleeping too much.

Most of us (myself included) eat a lot of junk food and candy if we don’t restrict ourselves. Does this mean that lots of junk food and candy is the “natural” or the “optimal” amount for health?

Obviously, no. Modern junk food and candy are unnatural superstimuli, much tastier and much more abundant than any natural food, so they end up overwhelming our brains with pleasure, especially given that we are bored at work, college, or in high school so much of the day.

What if the only food available to you was junk food and candy?

  • If you don’t eat any, you starve.
  • If you eat just enough to be lean, you’ll keep salivating at the sight of pizzas and ice cream and feel distracted and hungry all the time. Importantly, in this situation, the feeling of hunger does not mean that you should eat more – it’s your brain being overpowered by a superstimulus while being bored.
  • And if you eat way too much candy or pizza at once, you’ll be feeling terrible afterwards, however tasty the food was.

Most of us (myself included) sleep 7-9 hours if we don’t have any alarms in the morning and if we get out of bed when we feel like it. Does this mean that 7-9 hours of sleep is the “natural” or the “optimal” amount?

My thesis is: obviously, no. Modern sleep, in its infinite comfort, is an unnatural superstimulus that overwhelms our brains with pleasure and comfort (note: I’m not saying that it’s bad, simply that being in bed today is much more pleasurable than being in “bed” in the past.)

Think about sleep 10,000 years ago. You sleep in a cave, in a hut, or under the sky, with predators and enemy tribes roaming around. You are on a wooden floor, on an animal’s skin, or on the ground. The temperature will probably drop 5-10°C overnight, meaning that if you were comfortable when you were falling asleep, you are going to be freezing when you wake up. Finally, there’s moon shining right at you and all kinds of sounds coming from the forest around you.

In contrast, today: you sleep on your super-comfortable machine-crafted foam of the exact right firmness for you. You are completely safe in your home, protected by thick walls and doors. Your room’s temperature stays roughly constant, ensuring that you stay warm and comfy throughout the night. Finally, you are in a light and sound-insulated environment of your house. And if there’s any kind of disturbance you have eye masks and earplugs.

Does this sound “natural”?

Now, what if the only sleep available to you was modern sleep?

  • If you don’t sleep at all, you go crazy, because some amount of sleep is necessary.
  • If you sleep just enough to be awake during the day, you’ll be dreaming of getting a nap at the sight of a bed and will be distracted and sleepy all the time. Importantly, I claim, in this situation, the feeling of sleepiness does not mean that you should sleep more – it’s your brain being overpowered by a superstimulus while being bored.
  • And if you sleep way too much at once, you’ll be feeling terrible afterwards, however pleasant the sleep was.

Even if I convinced you about the “sleeping too much” part, you are still probably wondering: but what does depression have to do with anything? Isn’t sleeping a lot good for mental health? Well…

Depression <-> oversleeping. Mania <-> acute sleep deprivation

In this section, I argue that depression triggers/amplifies oversleeping while oversleeping triggers/amplifies depression. Similarly, mania triggers/amplifies acute sleep deprivation while acute sleep deprivation triggers/amplifies mania.

One of the most notable facts about sleep is just how interlinked excessive sleep is with depression and how interlinked sleep deprivation is with mania in bipolar people.

Someone in r/BipolarReddit asked: How many hours do you sleep when stable vs (hypo)manic? Depressed?

Here are all 8 answers that compare hours for manic and depressed states, I excluded answers that describe hypomania but do not describe mania or that only describe mania or only describe depression. note the consistency:

  • “Manic/hypomanic: 0-6 hours Stable: 7-9 hours Depressed: 10-19 hours”
  • “Manic, 2-3, hypo, 5-6, stable 8-9, depressed 10-12. 8 is the number I try to hit.”
  • “Severely depressed w/o mixed features - 12 to 15 hours Low to Moderate depressed w/o mixed - 10 hours, if no alarm. With alarm less, but super hangover Stable -Usually 7-9 hours Hypomanic taking sedating evening meds - 5 to 7 hours Hypomanic with no sedating evening meds - 3 to 5 hours Manic out of hand - 0 to 3 hours Manic in hospital put on maximum sedating meds or injections - 4 to 6 hours Mixed episodes = same as hypo(manic)”
  • “I try to get at least 8 hours but when I’m depressed I nap a lot. When I’m hypo I sleep pretty much the same but when I’m manic I’m lucky to get 3 hours. Huhs”
  • “Just got out of a manic episode. A few all-nighters, a lot of 3 hour nights, and a good night of sleep was 6 hours. Now I’m depressed and I’ve been sleeping from 9pm to noon and staying in bed for much longer after I’m awake.”
  • “Manic 2-4, stable 6-7, depressed 10-12”
  • “Around 15 hours of sleep per night while depressed, and between 0-4 hours per night while manic.”

Lack of sleep is such a potent trigger for mania that acute sleep deprivation is literally used to treat depression. Aside from ketamine, not sleeping for a night is the only medicine we have to quickly – literally overnight – and reliably (in ~50% of patients) improve mood in depressed patients (until they go to bed, unless you keep advancing their sleep phase Riemann, D., König, A., Hohagen, F., Kiemen, A., Voderholzer, U., Backhaus, J., Bunz, J., Wesiack, B., Hermle, L. and Berger, M., 1999. How to preserve the antidepressive effect of sleep deprivation: A comparison of sleep phase advance and sleep phase delay. European archives of psychiatry and clinical neuroscience, 249(5), pp.231-237. ). NOTE: DO NOT TRY THIS IF YOU ARE BIPOLAR, YOU MIGHT GET A MANIC EPISODE.

an essay on sleep

Figure 1. Copied from Wehr TA. Improvement of depression and triggering of mania by sleep deprivation. JAMA. 1992 Jan 22;267(4):548-51.

Why does the lack of sleep promote manic states while long sleep promotes depression? I don’t know. But here are a couple of pointers to interesting papers relevant to the question: Can non-REM sleep be depressogenic? Beersma DG, Van den Hoofdakker RH. Can non-REM sleep be depressogenic?. Journal of affective disorders. 1992 Feb 1;24(2):101-8. Brain-derived neurotrophic factor (BDNF) is associated with synapse growth. Sleep deprivation appears to increase BDNF [and therefore neurogenesis?]. Papers that showed up when I googled “sleep deprivation bdnf”: The Brain-Derived Neurotrophic Factor: Missing Link Between Sleep Deprivation, Insomnia, and Depression . Rahmani M, Rahmani F, Rezaei N. The brain-derived neurotrophic factor: missing link between sleep deprivation, insomnia, and depression. Neurochemical research. 2020 Feb;45(2):221-31. The link between sleep, stress and BDNF . Eckert A, Karen S, Beck J, Brand S, Hemmeter U, Hatzinger M, Holsboer-Trachsler E. The link between sleep, stress and BDNF. European Psychiatry. 2017 Apr;41(S1):S282-. BDNF: an indicator of insomnia? . Giese M, Unternährer E, Hüttig H, Beck J, Brand S, Calabrese P, Holsboer-Trachsler E, Eckert A. BDNF: an indicator of insomnia?. Molecular psychiatry. 2014 Feb;19(2):151-2. Recovery Sleep Significantly Decreases BDNF In Major Depression Following Therapeutic Sleep Deprivation . Goldschmied JR, Rao H, Dinges D, Goel N, Detre JA, Basner M, Sheline YI, Thase ME, Gehrman PR. 0886 Recovery Sleep Significantly Decreases BDNF In Major Depression Following Therapeutic Sleep Deprivation. Sleep. 2019 Apr;42(Supplement_1):A356-.

Jeremy Hadfield writes:

My (summarized/simplified) hypothesis based on what I’ve read: depression involves rigid, non-flexible brain states that correspond to rigid depressive world models. Depression also involves a non-updating of models or inability to draw new connections (brain is even literally slightly lighter in depressed patients). Sleep involves revising/simplifying world models based on connections learned during the day, involves pruning unneeded or irrelevant synaptic connections. Thus, excessive sleep + depression = even less world model updating, even more rigid brain, even fewer new connections. Sleep deprivation can resolve this problem at least temporarily by ensuring that you stay awake for longer and keep adding connections, thus compensating for the decreased connection-building caused by depression and “forcing” a brain update (perhaps through neural annealing - see QRI article).

Occasional acute sleep deprivation is good for health and promotes more efficient sleep

One other argument for sleeping the “natural” (7-9) number of hours is that we feel bad on days when we sleep less. In this section, I argue against this line of reasoning by asking: if fasting and exercising are good, shouldn’t acute sleep deprivation also be good? And I conclude that it is probably good.

Let’s continue our analogy of sleep to eating and add exercise to the mix.

It seems to me that most common arguments against acute sleep deprivation equally “demonstrate” that fasting and exercise are bad.

For example, I ran 7 kilometers 2 days ago and my legs still hurt like hell and I can’t run at all. Does this mean that running is “bad”?

Well, consensus seems to be that dizziness, muscle damage (and thus pain) and decreased physical performance after the run, are not just not bad, but are in fact necessary for the organism to train to run faster or to run longer distances by increasing muscle mass, muscle efficiency, and lung capacity.

What about fasting? When I fast, I am more anxious, I think about food a lot, meaning that focus is more difficult, and I feel cold. And if I decided to fast too much, I would pass out and then die. Does this mean that fasting is “bad”? Well, consensus seems to be that occasional fasting actually activates some “good” kind of stress, promotes healthy autophagy, (obviously) helps to lose weight, etc. and is in fact good.

Now, what happens when I sleep for 2 hours instead of 7 one night? I feel somewhat tingly in my hands, my mood is heightened a little bit, and, if I start watching a movie with my wife at 6pm, I’ll fall asleep. Does this mean that sleeping 2 hours one night is bad for my health?

Obviously no. The only thing we observe is that my organism was subjected to acute stress. However, the reaction to acute stress does not tell us anything about the long-term effects of this kind of stress. As we know, both in running and in fasting, short-term acute stress response results in adaptation and in long-term increase in performance and in benefit to the organism.

I combed through a lot of sleep literature and I haven’t seen a single study that made a parallel to either fasting or exercise and I haven’t seen a single pre-registered RCT that tried to see what happens to someone if you subject them to 1-3 nights per week of acute sleep deprivation and allow to recover the rest of the nights. Do they perform better or worse in the long-term on cognitive tests? Do they have more or less inflammation? Do they need less recovery sleep over time?

I think that the answers are:

  • Acute sleep deprivation combined with caffeine or some other stimulant that cancels out sleep pressure does not result in decreased cognitive ability at least until 30-40 hours of wakefulness (if this is true, then sleepiness , rather absence of sleep per se is responsible for decreased cognitive performance during acute sleep deprivation).
  • Occasional acute sleep deprivation has no impact on long-term cognitive ability or health.
  • Sleep does become more efficient over time and, in complete analogy to exercise, you withstand both acute sleep deprivation better and can function at baseline with a lower amount of sleep in the long-term.

(The only parallel to fasting I’m aware of anyone making is by Nassim Taleb… when he was quote-tweeting me.)

Appendix: anecdotes about acute sleep deprivation

Appendix: philipp streicher on homeostasis, its relationship to mania/depression, and on other points i make, our priors about sleep research should be weak.

In this section, I note that most sleep research is extremely unreliable and we shouldn’t conclude much on the basis of it.

Do you believe in power-posing? In ego depletion? In hungry judges and brain training?

If the answer is no, then your priors for our knowledge about sleep should be weak because “sleep science” is mostly just rebranded cognitive psychology, with the vast majority of it being small-n, not pre-registered, p-hacked experiments.

I have been able to find exactly one pre-registered experiment of the impact of prolonged sleep deprivation on cognition. It was published by economists from Harvard and MIT in 2021 and its pre-registered analysis found null or negative effects of sleep on all primary outcomes Bessone P, Rao G, Schilbach F, Schofield H, Toma M. The economic consequences of increasing sleep among the urban poor. The Quarterly Journal of Economics. 2021 Aug;136(3):1887-941. (note that both the abstract and the main body of this paper report results without the multiple-hypothesis correction, in contradiction to the pre-registration plan of the study. The paper does not mention this change anywhere. See comments for the details. ).

So why has sleep research not been facing a severe replication crisis, similar to psychology?

First, compared to psychology, where you just have people fill out questionnaires, sleep research is slow, relatively expensive, and requires specialized equipment (e.g. EEG, actigraphs). So skeptical outsiders go for easier targets (like social psychology) while the insiders keep doing the same shoddy experiments because they need to keep their careers going somehow .

Second, imagine if sleep researchers had conclusively shown that sleep is not important for memory, health, etc. – would they get any funding? No. Their jobs are literally predicated on convincing the NIH and other grantmakers that sleep is important. As Patrick McKenzie notes , “If you want a problem solved make it someone’s project. If you want it managed make it someone’s job.”

an essay on sleep

Figure 2. Relative risk of showing benefit or harm of treatment by year of publication for large NHLBI trials on pharmaceutical and dietary supplement interventions. Copied from Kaplan RM, Irvin VL. Likelihood of null effects of large NHLBI clinical trials has increased over time. PloS one. 2015 Aug 5;10(8):e0132382.

Figure 3. Eric Turner on Twitter: “Negative depression trials…Now you see ‘em, now you don’t. Published literature vs FDA, from [ Turner EH, Matthews AM, Linardatos E, Tell RA, Rosenthal R. Selective publication of antidepressant trials and its influence on apparent efficacy. New England Journal of Medicine. 2008 Jan 17;358(3):252-60. ]"

Even in medicine, without pre-registered RCTs truth is extremely difficult to come by, with more than one half Kaiser J. More than half of high-impact cancer lab studies could not be replicated in controversial analysis. AAAS Articles DO Group. 2021; of high-impact cancer papers failing to be replicated, and with one half of RCTs without pre-registration of positive outcomes being spun Kaplan RM, Irvin VL. Likelihood of null effects of large NHLBI clinical trials has increased over time. PloS one. 2015 Aug 5;10(8):e0132382. by researchers as providing benefit when there’s none. And this is in medicine, which is infinitely more consequential and rigorous than psychology.

Also see: Appendix: I have no trust in sleep scientists .

Decreasing sleep by 1-2 hours a night in the long-term has no negative health effects

In this section, I outline several lines of evidence that bring me to the conclusion that decreasing sleep by 1-2 hours a night in the long-term has no negative health effects. To summarize:

  • A sleep researcher who trains sailors to sleep efficiently in order to maximize their race performance believes that 4.5-5.5 hours of sleep is fine.
  • 70% of 84 hunter-gatherers studied in 2013 slept less than 7 hours per day, with 46% sleeping less than 6 hours.
  • A single-point mutation can decrease the amount of required sleep by 2 hours, with no negative side-effects.
  • A brain surgery can decrease the amount of sleep required by 3 hours, with no negative-side effects.
  • Sleep is not required for memory consolidation.
  • Claudio Stampi is a Newton, Massachusetts based sleep researcher. But he is not your normal sleep researcher whose career is built on observational studies or p-hacked n=20 experiments that always show “significant” results. He is one of the only sleep researchers with skin in the game: the goal of his research is to maximize performance of sailors by tinkering with their sleep cycles, and he believes that 4.5-5.5 hours of sleep is fine, The article uses the phrase “get by” and does not state that there’s no decrease in performance. However, it does state that the decrease in performance at 3 hours of sleep with lots of naps is 12-25%, so increasing sleep by 50-83% from this, seems unlikely to result in any decrease in performance, compared to 8 hours of sleep (“he had them shift to their three-hour routines. After more than a month, the monophasic group showed a 30 percent loss in cognitive performance. The group that divided its sleep between nighttime and short naps showed a 25 percent drop. But the polyphasic group, which slept exclusively in short naps, showed only a 12 percent drop."). as long as it’s broken down into core sleep and a series of short (usually 20-minute) naps. Here’s Outside :
“Solo sailing is one of the best models of 24/7 activity, and brains and muscles are required,” Stampi said one day at his home, from which he runs the institute. “If you sleep too much, you don’t win. If you don’t sleep enough, you break.” …
“For those sailors who are seriously competing, Stampi is a necessity,” says Brad Van Liew, a 37-year-old Californian who began working with Stampi in 1998 and went on to become America’s most accomplished solo racer and the winner in his class of the 2002-2003 Around Alone, a 28,000-mile global solo race. “You have to sleep efficiently, or it’s like having a bad set of sails or a boat bottom that isn’t prepared properly.” …
both Golding and MacArthur sleep about the same amount while racing, between 4.5 and 5.5 hours on average in every 24—the minimum amount, Stampi believes, on which humans can get by.

In 2013, scientists tracked the sleep of 84 hunter-gatherers from 3 different tribes Yetish G, Kaplan H, Gurven M, Wood B, Pontzer H, Manger PR, Wilson C, McGregor R, Siegel JM. Natural sleep and its seasonal variations in three pre-industrial societies. Current Biology. 2015 Nov 2;25(21):2862-8. (each person’s sleep was measured for about a week but measurements for different groups were taken in different parts of the year). The average amount of sleep among these 84 people was 6.5 hours. Judging by CDC’s “7 hours or more” recommendation , Consensus Conference Panel:, Watson, N.F., Badr, M.S., Belenky, G., Bliwise, D.L., Buxton, O.M., Buysse, D., Dinges, D.F., Gangwisch, J., Grandner, M.A. and Kushida, C., 2015. Joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society on the recommended amount of sleep for a healthy adult: methodology and discussion. Journal of Clinical Sleep Medicine, 11(8), pp.931-952. 70% out of these 84 undersleep:

  • 6 people slept between 4 and 5 hours
  • 19 people slept between 5 and 6 hours
  • 34 people slept between 6 and 7 hours
  • 21 people slept between 7 and 8 hours
  • 4 people slept between 8 and 9 hours

One group of hunter-gatherers (10 people from Tsimane tribe studied in November/December of 2013) slept just 5.6 hours on average.

The authors of this study also note that “None of these groups began sleep near sunset, onset occurring, on average, 3.3 hr after sunset” (they are probably getting too much artificial light… or something).

What I’m getting from all of this is: there’s nothing “natural” about sleeping 7-9 hours. If you think that the amount of sleep hunter-gatherers are getting is the amount of sleep humans have evolved to get, then you should not worry at all about getting 4, 5, or 6 hours of sleep a night.

The CDC and the professional sleep researchers pull the numbers out of their asses without any kind of rigorous scientific evidence for their “consensus recommendations”. There’s no causal evidence that sleeping 7-9 hours is healthier than sleeping 6 hours or less. Correlational evidence suggests Shen X, Wu Y, Zhang D. Nighttime sleep duration, 24-hour sleep duration and risk of all-cause mortality among adults: a meta-analysis of prospective cohort studies. Scientific Reports. 2016 Feb 22;6:21480. that people who sleep 4 hours have the same if not lower mortality as those who sleep 8 hours and that people who sleep 6-7 hours have the lowest mortality.

an essay on sleep

Also see: Appendix: Jerome Siegel and Robert Vertes vs the sleep establishment

It appears that there is a distinct single-point mutation that allows some people to sleep several hours less than typical on average. A Rare Mutation of β1-Adrenergic Receptor Affects Sleep/Wake Behaviors : Shi G, Xing L, Wu D, Bhattacharyya BJ, Jones CR, McMahon T, Chong SC, Chen JA, Coppola G, Geschwind D, Krystal A. A rare mutation of β1-adrenergic receptor affects sleep/wake behaviors. Neuron. 2019 Sep 25;103(6):1044-55.

We have identified a mutation in the β1-adrenergic receptor gene in humans who require fewer hours of sleep than most. In vitro, this mutation leads to decreased protein stability and dampened signaling in response to agonist treatment. In vivo, the mice carrying the same mutation demonstrated short sleep behavior. We found that this receptor is highly expressed in the dorsal pons and that these ADRB1+ neurons are active during rapid eye movement (REM) sleep and wakefulness. Activating these neurons can lead to wakefulness, and the activity of these neurons is affected by the mutation. These results highlight the important role of β1-adrenergic receptors in sleep/wake regulation.

The study compares carriers of the mutation in one family to non-carriers in the same family and finds that carriers sleep about 2 hours per day less. Given the complexity of sleep and the multitude of its functions, it seems extremely implausible that just one mutation in the β1-adrenergic receptor gene was able to increase its efficiency by about 25%. It seems that it just made carriers sleep less (due to more stimulation of a group of neurons in the brain responsible for sleep/wakefulness) without anything else obviously changing when compared to non-carriers.

A similar example of a drop in the amount of sleep required without negative side effects and driven by a single factor was described in Development of a Short Sleeper Phenotype after Third Ventriculostomy in a Patient with Ependymal Cysts . Seystahl K, Könnecke H, Sürücü O, Baumann CR, Poryazova R. Development of a short sleeper phenotype after third ventriculostomy in a patient with ependymal cysts. Journal of Clinical Sleep Medicine. 2014 Feb 15;10(2):211-3. To sum up: a 59-year-old patient had chronic hydrocephalus. An endoscopic third ventriculostomy was performed on him. His sleep dropped from 7-8 hours a night to 4-5 hours a night without him becoming sleepy, he stopped being depressed, and his physical or cognitive performance stayed normal, as measured by the doctors.

Sleep is not required for memory consolidation. Jerome Siegel (the author of the hunter-gatherers study mentioned above) writes in Memory Consolidation Is Similar in Waking and Sleep : Siegel JM. Memory Consolidation Is Similar in Waking and Sleep. Current Sleep Medicine Reports. 2021 Mar;7(1):15-8.

Under interference conditions, such as exist during sleep deprivation, subjects, by staying awake, necessarily interacting with the experimenter keeping them awake and experiencing the laboratory environment, will remember more than just the items that are presented. But they may be less able to recall the particular items the experimenter is measuring. This can lead to the mistaken conclusion that sleep is required for memory consolidation [7].
Recent work has, for the first time, dealt with this issue. It was shown that a quiet waking period or a meditative waking state in which the environment is being ignored, produces a gain in recall similar to that seen in sleep, relative to an active waking state or a sleep-deprived state [8–16]. …
REM sleep has been hypothesized to have a key role in memory consolidation [20]. But it has been reported that near total REM sleep deprivation for a period of 14 to 40 days by administration of the monoamine oxidase inhibitor phenelzine has no apparent effect on cognitive function in humans [21]. A systematic study using serotonin or norepinephrine re-uptake inhibitors to suppress REM sleep in humans had no deleterious effects on a variety of learning tasks [22, 23]. Humans rarely survive the damage to the pontine region which when discretely lesioned in animals greatly reduces or eliminates REM sleep [20, 23–25]. However, one such subject with pontine damage that severely reduced REM sleep has been thoroughly studied. The studies show normal or above normal cognitive performance and no deficit in memory formation or recall [26•]. It has been claimed that learning results in greater total amounts of sleep, or greater amounts of REM sleep [27], or greater amounts of sleep spindles, or slow wave activity. However, a systematic test of this hypothesis in 929 human subjects with night-long EEG recording found no such correlation with retention [28•].

The entire Scientific Consensus™ about sleep being essential for memory consolidation appears to be heavily flawed, driven by people like Matthew Walker, and making me lose the last remnants of trust in sleep science that I had .

Appendix: how I wake up after 6 or less hours of sleep

Appendix: anecdotes about long-term sleep deprivation.

  • Appendix: the idea that sleep’s purpose is metabolite clearance, if not total bs, is massively overhyped
Chadwick worked for several nights straight without sleep on the seminal discovery [of the neutron, for which he was awarded the 1935 Nobel in physics]. When he was done he went to a meeting of the Kapitza Club at Cambridge and gave a talk about it, ending with the words, “Now I wish to be chloroformed and put to sleep”.

I’m not what they call a “natural short sleeper”. If I don’t restrict my sleep, I often sleep more than 8 hours and I still struggle with getting out of bed. I used to be really scared of not sleeping enough and almost never set the alarm for less than 7.5 hours after going to bed.

My sleep statistics tells me that I slept an average of 5:25 hours over the last 7 days, 5:49 hours over the last 30 days, and 5:57 over the last 180 days hours, meaning that I’m awake for 18 hours per day instead of 16.5 hours. I usually sleep 5.5-6 hours during the night and take a nap a few times a week when sleepy during the day.

This means that I’m gaining 33 days of life every year. 1 more year of life every 11 years. 5 more years of life every 55 years.

Why are people not all over this? Why is everyone in love with charlatans who say that sleeping 5 hours a night will double your risk of cancer, make you pre-diabetic, and cause Alzheimer’s, despite studies showing that people who sleep 5 hours have the same, if not lower, mortality than those who sleep 8 hours? Convincing a million 20-year-olds to sleep an unnecessary hour a day is equivalent, in terms of their hours of wakefulness, to killing 62,500 of them.

I wrote large chunks of this essay having slept less than 1.5 hours over a period of 38 hours. I came up with and developed the biggest arguments of it when I slept an average of 5 hours 39 minutes per day over the preceding 14 days. At this point, I’m pretty sure that the entire “not sleeping ‘enough’ makes you stupid” is a 100% psyop. It makes you somewhat more sleepy, yes. More stupid, no. I literally did an experiment in which I tried to find changes in my cognitive ability after sleeping 4 hours a day for 12-14 days , I couldn’t find any. My friends who I was talking to a lot during the experiment simply didn’t notice anything.

What do I lose due to sleeping 1.5 hours a day less? I’m somewhat more sleepy every day and staying awake during boring calls is even more difficult now. On the other hand, just a prospect of playing an exciting video game, makes me 100% alert even after sleeping for 2-3 hours. Related: Horne JA, Pettitt AN. High incentive effects on vigilance performance during 72 hours of total sleep deprivation. Acta psychologica. 1985 Feb 1;58(2):123-39. There’s no guarantee that what I’m doing is healthy after all, although, as I explained above, I think that it’s extremely unlikely due to likely adaptation, and likely beneficial effects of sleep deprivation (e.g. increased BDNF, less susceptibility to depression), and since I take a 20-minute nap under my wife’s watch whenever I don’t feel good.

an essay on sleep

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Acknowledgements

I would like to thank (in reverse alphabetic order): Misha Yagudin , Guy Wilson , Bart Sturm, Ulysse Sabbag , Stephen Malina , Gavin Leech , Anastasia Kuptsova , Jake Koenig , Aleksandr Kotyurgin, Alexander Kim , Basil Halperin , Jeremy Hadfield , Steve Gadd , and Willy Chertman for reading drafts of this essay and for disagreeing with many parts of it vehemently. All errors mine.

Guzey, Alexey. Theses on Sleep. Guzey.com. 2022 February. Available from https://guzey.com/theses-on-sleep/ .

Or download a BibTeX file here .

  • One popular sleep tip I’ve come to wholeheartedly believe is the importance of waking up at the same time: from my experience, it does really seem that the organism adjusts the time it is ready to wake up if you keep a consistent schedule.
  • observation: I find staying awake during boring lectures impossible and reliably fall asleep during them, regardless of the amount of sleep I’m getting
  • observation: I can play video games with little sleep for several days and feel 100% alert (a superstimulus of its own, but still a valuable observation)
  • observation: I become sleepy when I’m working on something boring and difficult

Common objections

Objection: “When I’m underslept I notice that I’m less productive.”

Yes, this is expected as per the analogy to exercise I make above . After exercise you are tired but over time you become stronger.

It might be that undersleeping itself causes you to be less productive. However, it might also be the case that there’s an upstream cause that results in both undersleeping and lack of productivity. I think either could be the case depending on the person but understanding what exactly happens is much harder than people typically appreciate when they notice such co-occurrences.

an essay on sleep

As Nick Wignall notes on Twitter:

People are also not great at distinguishing true sleepiness from tiredness.
Analogy would be: of all the times when you feel hungry, how much of that is true hunger vs a craving?

Also related: when people say that e.g. they have a small child, are doing medical residency, etc. and feel terrible due to undersleep, note that there’s a big difference between being randomly forced to not sleep when you want to sleep and managing one’s sleep consciously. The analogy would be to saying that fasting is bad because if you are forbidden by someone from eating randomly throughout the day.

Objection: “Driving when you are sleepy is dangerous, therefore you are wrong.”

Answer: Yep, I agree that driving while being sleepy is dangerous and I don’t want anyone to drive, to operate heavy machinery, etc. when they are sleepy. This, however, bears no relationship on any of the arguments I make.

Objection: “The graph that shows more sleep being associated with higher doesn’t tell us anything because sick people tend to sleep more.”

Answer: It is true that some diseases lead to prolonged sleep. However, some diseases also lead to shortened sleep. For example, many stroke patients suffer from insomnia Sterr A, Kuhn M, Nissen C, Ettine D, Funk S, Feige B, Umarova R, Urbach H, Weiller C, Riemann D. Post-stroke insomnia in community-dwelling patients with chronic motor stroke: physiological evidence and implications for stroke care. Scientific Reports. 2018 May 30;8(1):8409. and people with fatal familial insomnia struggle with insomnia. Therefore, if you want to make the argument that the association between longer sleep and higher mortality is not indicative of the effect of sleep, you have to accept that the same is true about shorter sleep and higher mortality.

Appendix: I have no trust in sleep scientists

Why do I bother with all of this theorizing? Why do I think I can discover something about sleep that thousands of them couldn’t discover over many decades?

The reason is that I have approximately 0 trust in the integrity of the field of sleep science.

As you might be aware, 2 years ago I wrote a detailed criticism of the book Why We Sleep written by a Professor of Neuroscience at psychology at UC Berkeley, the world’s leading sleep researcher and the most famous expert on sleep, and the founder and director of the Center for Human Sleep Science at UC Berkeley, Matthew Walker.

Here are just a few of biggest issues (there were many more) with the book.

Walker wrote: “Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer”, despite there being no evidence that cancer in general and sleep are related. There are obviously no RCTs on this, and, in fact, there’s not even a correlation between general cancer risk and sleep duration.

Walker falsified a graph from an academic study in the book.

Walker outright fakes data to support his “sleep epidemic” argument. The data on sleep duration Walker presents on the graph below simply does not exist :

an essay on sleep

Here’s some actual data on sleep duration over time:

an essay on sleep

By the time my review was published, the book had sold hundreds of thousands if not millions of copies and was praised by the New York Times , The Guardian , and many other highly-respected papers. It was named one of NPR’s favorite books of 2017 while Walker went on a full-blown podcast tour.

Did any sleep scientists voice the concerns they with the book or with Walker? No. They were too busy listening to his keynote at the Cognitive Neuroscience Society 2019 meeting.

Did any sleep scientists voice their concerns after I published my essay detailing its errors and fabrications? No (unless you count people replying to me on Twitter as “voicing a concern”).

Did Walker lose his status in the community, his NIH grants, or any of his appointments? No, no, and no.

I don’t believe that a community of scientists that refuses to police fraud and of which Walker is a foremost representative (recall that he is the director of the Center for Human Sleep Science at UC Berkeley) could be a community of scientists that would produce a trustworthy and dependable body of scientific work.

Appendix: the idea that sleep’s purpose is metabolite clearance, if not total bs, is massively overhyped

Specifically, the original 2013 paper Xie L, Kang H, Xu Q, Chen MJ, Liao Y, Thiyagarajan M, O’Donnell J, Christensen DJ, Nicholson C, Iliff JJ, Takano T. Sleep drives metabolite clearance from the adult brain. science. 2013 Oct 18;342(6156):373-7. accumulated more than 3,000 (!) citations in less than 10 years and is highly misleading.

The paper is called “Sleep Drives Metabolite Clearance from the Adult Brain”. The abstract says:

The conservation of sleep across all animal species suggests that sleep serves a vital function. We here report that sleep has a critical function in ensuring metabolic homeostasis. Using real-time assessments of tetramethylammonium diffusion and two-photon imaging in live mice, we show that natural sleep or anesthesia are associated with a 60% increase in the interstitial space, resulting in a striking increase in convective exchange of cerebrospinal fluid with interstitial fluid. In turn, convective fluxes of interstitial fluid increased the rate of β-amyloid clearance during sleep. Thus, the restorative function of sleep may be a consequence of the enhanced removal of potentially neurotoxic waste products that accumulate in the awake central nervous system.

At the same time, the paper found that anesthesia without sleep results in the same clearance (paper: “Aβ clearance did not differ between sleeping and anesthetized mice”), meaning that clearance is not caused by sleep per se, but instead only co-occurrs with it. Authors did not mention this in the abstract and mistitled the paper, thus misleading the readers. As far as I can tell, literally nobody pointed this out previously.

And on top of all of this “125I-Aβ1-40 was injected intracortically”, meaning that they did not actually find any brain waste products that would be cleared out. This is an exogenous compound that was injected god knows where disrupting god knows what in the brain.

Max Levchin in Founders at Work :

The product wasn’t really finished, and about a week before the beaming at Buck’s I realized that we weren’t going to be able to do it, because the code wasn’t done. Obviously it was really simple to mock it up—to sort of go, “Beep! Money is received.” But I was so disgusted with the idea. We have this security company; how could I possibly use a mock-up for something worth $4.5 million? What if it crashes? What if it shows something? I’ll have to go and commit ritual suicide to avoid any sort of embarrassment. So instead of just getting the mock-up done and getting reasonable rest, my two coders and I coded nonstop for 5 days. I think some people slept; I know I didn’t sleep at all. It was just this insane marathon where we were like, “We have to get this thing working.” It actually wound up working perfectly. The beaming was at 10:00 a.m.; we were done at 9:00 a.m.

/u/CPlusPlusDeveloper on Gwern’s Writing in the Morning :

We know that acute sleep deprivation seems to have a manic and euphoric effect on at least some percent of the population some percent of the time. For example staying up all night is one of the most effective ways to temporarily aleve depression. Of course the problem is that chronic sleep deprivation has the opposite effect, and the temporary mania and euphoria is not sustainable.
My speculative take is that whatever this mechanism, it was the main reason you experienced a productivity boost. By waking up early you intentionally were fighting against your chronobiology, hence adding an element of acute sleep deprivation regardless of how many hours you got the night before. That mania fuels an amphetamine like focus.
The upshot, if my hypothesis is true, is that waking up early would not produce similar gains if you did it everyday. Like the depressive who stays up all night, it may feels like you’ve discovered an intervention that will pay lasting gains. But if you were to actually make it part of your recurring lifestyle, the benefits would stop, and eventually the impact would work in reverse.
Along those lines that’s probably why you naturally tend to stop conforming to that pattern after a few days. As acute sleep deprivation becomes chronic, you’re most likely intuitively recognizing that the pattern has crossed over to the point of being counter-productive.

Lots of writers and software engineers note that their creative juices start flowing by evening extending late into the night - I think this phenomenon is closely related to the one described in the comment above.

Brian Timar :

sleep anecdote- In undergrad I had zero sleep before several major tests; also before quals in grad school. Basically wouldn’t sleep before things I really considered important (this included morning meetings I didn’t want to miss!). On such occasions I would feel:
miserable, then absurd and in a good humor, weirdly elated, then Super PumpedTM, and
really sharp when the test (or whatever) actually started.

Appendix: a well-documented case-study of a person living without sleep for 4 months

Total Wake: Natural, Pathological, and Experimental Limits to Sleep Reduction , Panchin Y, Kovalzon VM. Total Wake: Natural, Pathological, and Experimental Limits to Sleep Reduction. Frontiers in neuroscience. 2021 Apr 7;15:288. quoting Le sommeil, la conscience et l’éveil : Jouvet M. Le sommeil, la conscience et l’éveil. Odile Jacob; 2016 Mar 9.

There is such pathology as Morvan’s disease, in which quasi-wakefulness, which lasted 3,000 h (more precisely, 2,880), or 4 months, was not accompanied by sleep rebound, since the sleep generation system itself was disturbed.” Throughout this period the patient was under continuous polysomnographic control, so his agrypnia was confirmed objectively. Jouvet conclude that “… slow wave (NREM) and paradoxical (REM) sleep are not necessary for life (at least for 4–5 months for the first and about 8 months for the second), and we cannot consider their suppression to be the cause of any serious disorders in the body. A person who had lack of sleep and dreams for 4 months, of which there are only a few minutes of nightly hallucinations, can turn out to read newspapers during the day, make plans, play cards and win, and at the same time lie on the bed in the dark all night without sleep! In conclusion, we admit: this observation makes most theories about the functions of sleep and paradoxical (REM) sleep obsolete at once, but offers nothing else

I once tried to cheat sleep, and for a year I succeeded (strong peak-performance-sailing vibes):

In the summer of 2009, I was finishing the first—and toughest—year of my doctorate. …
To keep up this crazy sleep schedule, I always needed a good reason to wake up the next morning after my 3.5-hour nighttime sleep. So before I went to bed, I reviewed the day gone past and planned what I would do the next day. I’ve carried on with this habit, and it serves me well even today.
But the Everyman schedule was reasonably flexible. Some days when I missed a nap, I simply slept a little more at night. There were also days when I couldn’t manage a single nap, but it didn’t seem to affect me very much the next day.
To the surprise of many, and even myself, I had managed to be on the polyphasic schedule for more than a year. But then came a conference where for a week I could not get a single nap. It was unsettling but I was sure I would be able to get back to sleeping polyphasic without too much trouble.
I was wrong. When I tried to get back into the schedule, I couldn’t find the motivation to do it; I didn’t have the same urgent goals that I had had a year ago. So I returned to sleeping like an average human.

James Gleck in Chaos on Mitch Feigenbaum:

In the spring of 1976 he entered a mode of existence more intense than any he had lived through. He would concentrate as if in a trance, programming furiously, scribbling with his pencil, programming again. He could not call C division for help, because that would mean signing off the computer to use the telephone, and reconnection was chancy. He could not stop for more than five minutes’ thought, because the computer would automatically disconnect his line. Every so often the computer would go down anyway, leaving him shaking with adrenaline. He worked for two months without pause. His functional day was twenty-two hours. He would try to go to sleep in a kind of buzz, and awaken two hours later with his thoughts exactly where he had left them. His diet was strictly coffee. (Even when healthy and at peace, Feigenbaum subsisted exclusively on the reddest possible meat, coffee, and red wine. His friends speculated that he must be getting his vitamins from cigarettes.)
In the end, a doctor called it off. He prescribed a modest regimen of Valium and an enforced vacation. But by then Feigenbaum had created a universal theory.

Ryan Kulp’s experience with decreasing the amount of sleep by several hours :

i began learning to code in 2015. since i was working full-time i needed to maximize after-hours to learn quickly. i experimented for 10 days straight… go to sleep at 4am, wake up at 8am for work. felt fine.
actually, the first 5-10 minutes of “getting up” after 3-4 hours of sleep sucks more than if i sleep ~8 hours. but after 15 mins of moving around, a shower, etc, i feel as if i slept 8 hours.
since then i’ve routinely slept 4-6 hours /day and definitely been more productive. i think if more people experimented for themselves and had the same “aha” moment i did (that you feel fine after the initial gut-wrenching “i slept too little” reaction), they’d get more done too.

This is a very good point that shows that: there’s (1) how sleepy we feel when waking up and (2) how sleepy we feel during the day. (2) is probably more important but most people are focused on (1) and the implicit assumption is that poor (1) leads to (2) – which is unwarranted.

Also: https://twitter.com/BroodVx/status/1492227577896787969,

Nabeel Qureshi writes:

you’re combining two things here: (1) your brain is overpowered by the comfy soft temp-controlled bed (2) you’re bored. they might both be right but i think you conflate them, and they’re separate arguments. this is important bc i think the strongest counterargument to what you’re saying is the classic experience of: you force yourself to wake up early (say 6), you have a project you’re genuinely excited about (hence #2 is false), but when you sit down to work, you’re tired and can’t quite focus. in this scenario, i think your theory would say that i’m not really that excited about what i’m doing, because if i were (see video game argument) then i’d be awake. i’d disagree and say that the researcher should just go take a nap, and they’ll probably be able to make more progress per hour than the extra hours they gain… trying to force yourself to do something while underslept, subjectively, feels hellish. i’m sure you’ve had this experience - did you figure out a workaround?

It is completely true that if you are excited by a project but it’s not super stimulating, it’s still very easy to wake up after less than usual number of hours of sleep and feel sleepy and terrible. This is true for me as well. I found a solution to this: instead of heading straight to the computer, I first unload the clean plates from the dishwasher and load it with dirty plates. This activity is quite special in that it is:

  • Why this matters: moving around wakes up the body much better than just sitting.
  • Why this matters: moving around in automatic pre-defined movements eventually results in the brain just performing these movements on autopilot without waking up.
  • Why this matters: I and people I know tend to find intense physical activities right after waking up really unpleasant and somewhat nauseating.

In about 90% of the cases, 10 minutes later when I’m done with the dishwasher, I find that I’m fully awake and don’t actually want to sleep anymore. In the remaining 10% of the cases, I stay awake and work until my wife wakes up and then go take a 20-minute nap under her watch (and take as many 20-minute naps as I need during the day, although I only end up taking a few naps a week and rarely more than one per day, unless I’m sick).

Appendix: Elon Musk on working 120 hours a week and sleep

On Tesla’s first-quarter earnings conference call in May, Musk referred to inquiries from Wall Street analysts as “boring, bonehead questions” and as “so dry. They’re killing me.” On the next earnings conference call in August, Musk said he was sorry for “being impolite” on the previous call.
“Obviously I think there’s really no excuse for bad manners and I was violating my own rule in that regard. There are reasons for it, I got no sleep, 120 hour weeks, but nonetheless, there is still no excuse, so my apologies for not being polite on the prior call,” Musk said.
Later in August, in conversation with the New York Times, Musk reported using prescription sleep medication Ambien to sleep.
“Yeah. It’s not like for fun or something,” Musk told Swisher Wednesday. “If you’re super stressed, you can’t go to sleep. You either have a choice of, like, okay, I’ll have zero sleep and then my brain won’t work tomorrow, or you’re gonna take some kind of sleep medication to fall asleep.”
Musk said he was working such insane hours to get Tesla through the ramp up in production for its Model 3 vehicle. ”[A]s a startup, a car company, it is far more difficult to be successful than if you’re an established, entrenched brand. It is absurd that Tesla is alive. Absurd! Absurd.”

Philipp ( @Cautes ):

First, I wanted to share a way of thinking about some of your findings that builds on the idea of a homeostatic control system (brought to you from engineering via cybernetics). The classic example is a thermostat, which keeps temperature of a room close to a set point. Biology is quite a bit more messy than this, of course, but the body makes use of a plenty of feedback mechanisms to stay close to set points as well. You’re right in pointing out that these set points don’t need to be healthy though. For example, measured via EEG, PTSD patients have alpha power (which primarily modulates neural inhibition in frontal, parietal and occipital areas of the brain) set points far below that of healthy control groups. One way to deal with these suboptimal set points is to simply disrupt the system. Here’s a model that makes this point nicely: imagine all possible brain state dynamics as a two-dimensional plane and place a ball on it which represents the current brain state space. As the ball moves, the brain dynamics change as well (in frequency, phase, amplitude - you name it). On the plane, you have basins that give stability to the brain state, and repellers in the form of hills, as well as random noise and outside interference which drives the ball into various directions. Sometimes the ball will get stuck in basins which are highly suboptimal, but they are deep enough that exploration of other set points is not possible. If the system is disrupted, the ball might get jolted out of its basin though, and be again able to fall into a more optimal position.
With that said, there’s plenty of evidence that stability in itself (even within better basins) is suboptimal for perfect health, because contexts change. For example, people who are very physically healthy (athletes, for example), tend to have far greater variance in the time interval between individual heart beats (heart rate variability) than even the average person, and as the average person gets healthier, their heart rate variability increases as well. Basically, the body becomes more resilient by introducing a noise signal that produces chaotic fluctuations to homeostatic control mechanisms (controlled allostasis) and there are good reasons to think that this is true of psychological health as well.
Because of this, I think that you’re right in suggesting that varying the amount of time you sleep is a good thing - especially if you’re currently struggling with depression or mania. Not even necessarily because sleep per se is the culprit, but because it might dislodge a ball stuck in a suboptimal basin, so to speak. Depressed people tend to oversleep, people with mania tend to sleep too little, so steering in the opposite direction is only logical. For perfectly healthy people, sleep cycling is probably the best way to go - kind of a mirroring the logic of heart rate variability: introduce some noise to keep your body on your toes. It’s just like fasting, working out, cold exposure, saunas, etc. - it’s al about producing stressors on the body which stir up repair processes which keep you healthy (and biologically younger). I have done plenty of self-experiments with polyphasic 5-6 hour sleeping (similar to the the approach studied by Stampi, who you mentioned), with no negative consequences. The main thing that makes it impractical is that intermittent napping is sometimes hard to combine with professional responsibilities and a social life.
As a side note, because you ask the question about why depressed people sleep longer, and people with mania sleep less, the answer to this is very likely highly multi-causal. With that said, I wanted to point out that depressed people generally exhibit excessive alpha activity in eyes-open waking states, which normally becomes more pronounced in people as they drift off to sleep (because of the neural inhibition function). We also have reason to believe that it mediates between BDNF and subclinical depressed mood, so that’s a link to something else you talk about in your article. As for mania, I haven’t looked at this myself, but I remember hearing that it’s almost a mirror image, with generally decreased synchronisation of slower oscillations and heightened faster rhythms, generally associated with greater arousal and wakefulness.
One last thing: as you point out, sleep is likely not required for memory retention. Any claim that sleep is about any specific cognitive function should be suspect on the principle that the phenomenon of sleep predates the development of organisms with brains - it can’t have evolved specifically for something as high-level as memory retention. It’s more likely about something more basic like general metabolic health.

Appendix: Jerome Siegel and Robert Vertes vs the sleep establishment

Time for the Sleep Community to Take a Critical Look at the Purported Role of Sleep in Memory Processing Vertes RP, Siegel JM. Time for the sleep community to take a critical look at the purported role of sleep in memory processing. Sleep. 2005 Oct 1;28(10):1228-9. by Robert Vertes and Jerome Siegel (a reply to Walker claiming that the debate on memory processing in sleep is essentially settled):

The present ‘debate’ was sparked by an editorial by Robert Stickgold in SLEEP on an article in that issue by Schabus et a on paired associate learning and sleep spindles in humans
Regarding Stickgold’s editorial, I was particularly troubled by his opening statement, as follows: “The study of sleep-dependent memory consolidation has moved beyond the question of whether it exists to questions of its extent and of the mechanisms supporting it”. He then proceeded to cite evidence justifying this statement. Surprisingly, there was no mention of opposing views or a discussion of data inconsistent with the sleep-memory consolidation (S-MC) hypothesis. It seemed that the controversial nature of this issue should have at least been acknowledged, but apparently to do so would have undermined Stickgold’s position that the door is closed on this debate and only the fine points need be resolved. …
By all accounts, sleep does not serve a role in declarative memory. As reviewed by Smith, with few exceptions, reports have shown that depriving subjects of REM sleep does not disrupt learning/memory, or exposure to intense learning situations does not produce subsequent increases in REM sleep. Smith concluded: “REM sleep is not involved with consolidation of declarative material.” The study by Schabus et al (see above) is another example that the learning of declarative material is unaffected by sleep. They reported that subjects showed no significant difference in the percentage of word-pairs correctly recalled before and after 8 hours of sleep. Or as Stickgold stated in his editorial [the editorial Vertes and Siegel are replying to], “Performance in the morning was essentially unchanged from the night before”. It would seem important for Stickgold/Walker to acknowledge that the debate on sleep and memory has been reduced to a consideration of procedural memory – to the exclusion of declarative memory. If there are exceptions, they should note. Several lines of evidence indicate that REM sleep is not involved in memory processing/consolidation – or at least not in humans. Perhaps the strongest argument for this is the demonstration that the marked suppression or elimination of REM sleep in individuals with brainstem lesions or on antidepressant drugs has no detrimental effect on cognition. A classic case is that of an Israeli man who at the age of 19 suffered damage to the brainstem from shrapnel from a gunshot wound, and when examined at the age of 33 he showed no REM sleep. The man, now 55, is a lawyer, a painter and interestingly the editor of a puzzle column for an Israeli magazine. Recently commenting on his ‘famous’ patient, Peretz Lavie stated that “he is probably the most normal person I know and one of the most successful ones”. There are several other well documented cases of individuals with greatly reduced or absent REM sleep that exhibit no apparent cognitive deficits. It would seem that these individuals would be a valuable resource for examining the role of sleep in memory. …

In Memory Consolidation Is Similar in Waking and Sleep cited above, Siegel notes: Siegel JM. Memory Consolidation Is Similar in Waking and Sleep. Current Sleep Medicine Reports. 2021 Mar;7(1):15-8.

To critically evaluate this hypothesis [that sleep has a critical role in memory consolidation], we must take “interference” effects into account. If you learn something before or after the experimenter induced learning that is being measured in the typical sleep-memory study, it degrades recall of the tested information. For example if you tell a subject that the capital of Australia is Canberra and then allow the subject to have a normal night’s sleep, there is a high probability that the subject will remember this upon awakening. If on the other hand you tell the subject that the capital of Australia is Canberra, the capital of Brazil is Brasilia, the capital of Canada is Ottawa, the capital of Iceland is Reykjavik, the capital of Libya is Tripoli, the capital of Pakistan is Islamabad, etc., it is much less likely the subject will remember the capital of Australia. The effect of proactive and retroactive interference is dependent on the temporal juxtaposition, complexity, and similarity of the encountered material to the associations being tested. Interference is a well-established concept in the learning literature [1–6]. Under interference conditions, such as exist during sleep deprivation, subjects, by staying awake, necessarily interacting with the experimenter keeping them awake and experiencing the laboratory environment, will remember more than just the items that are presented. But they may be less able to recall the particular items the experimenter is measuring. This can lead to the mistaken conclusion that sleep is required for memory consolidation [7].

Fur Seals Suppress REM Sleep for Very Long Periods without Subsequent Rebound : Lyamin OI, Kosenko PO, Korneva SM, Vyssotski AL, Mukhametov LM, Siegel JM. Fur seals suppress REM sleep for very long periods without subsequent rebound. Current Biology. 2018 Jun 18;28(12):2000-5.

Virtually all land mammals and birds have two sleep states: slow-wave sleep (SWS) and rapid eye movement (REM) sleep [1, 2]. After deprivation of REM sleep by repeated awakenings, mammals increase REM sleep time [3], supporting the idea that REM sleep is homeostatically regulated. * Some evidence suggests that periods of REM sleep deprivation for a week or more cause physiological dysfunction and eventual death [4, 5]. However, separating the effects of REM sleep loss from the stress of repeated awakening is difficult [2, 6]. The northern fur seal (Callorhinus ursinus) is a semiaquatic mammal [7]. It can sleep on land and in seawater. The fur seal is unique in showing both the bilateral SWS seen in most mammals and the asymmetric sleep previously reported in cetaceans [8]. Here we show that when the fur seal stays in seawater, where it spends most of its life [7], it goes without or greatly reduces REM sleep for days or weeks. After this nearly complete elimination of REM, it displays minimal or no REM rebound upon returning to baseline conditions. Our data are consistent with the hypothesis that REM sleep may serve to reverse the reduced brain temperature and metabolism effects of bilateral nonREM sleep, a state that is greatly reduced when the fur seal is in the seawater, rather than REM sleep being directly homeostatically regulated. This can explain the absence of REM sleep in the dolphin and other cetaceans and its increasing proportion as the end of the sleep period approaches in humans and other mammals.

Appendix: more papers I found interesting

The end of sleep: ‘Sleep debt’ versus biological adaptation of human sleep to waking needs : Horne J. The end of sleep:‘sleep debt’versus biological adaptation of human sleep to waking needs. Biological psychology. 2011 Apr 1;87(1):1-4.

It is argued that the latter part of usual human sleep is phenotypically adaptable (without ‘sleep debt’) to habitual shortening or lengthening, according to environmental influences of light, safety, food availability and socio-economic factors, but without increasing daytime sleepiness. Pluripotent brain mechanisms linking sleep, hunger, foraging, locomotion and alertness, facilitate this time management, with REM acting as a ‘buffer’ between wakefulness and nonREM (‘true’) sleep. The adaptive sleep range is approximately 6–9 h, although, a timely short (<20 min) nap can equate to 1 h ‘extra’ nighttime sleep. Appraisal of recent epidemiological findings linking habitual sleep duration to mortality and morbidity points to nominal causal effects of sleep within this range. Statistical significance, here, may not equate to real clinical significance. Sleep durations outside 6–9 h are usually surrogates of common underlying causes, with sleep associations taking years to develop. Manipulation of sleep, alone, is unlikely to overcome these health effects, and there are effective, rapid, non-sleep, behavioural countermeasures. Sleep can be taken for pleasure, with minimal sleepiness; such ‘sleepability’ is ‘unmasked’ by sleep-conducive situations. Sleep is not the only anodyne to sleepiness, but so is wakefulness, inasmuch that some sleepiness disappears when wakefulness becomes more challenging and eventful. A more ecological approach to sleep and sleepiness is advocated.

Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory Pravosudov VV. Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory. Proceedings of the Royal Society of London. Series B: Biological Sciences. 2003 Dec 22;270(1533):2599-604.

It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is not clear whether such chronic but moderate elevations may be adaptive. I implanted wild–caught food–caching mountain chickadees (Poecile gambeli), which rely at least in part on spatial memory to find their caches, with 90–day continuous time–release corticosterone pellets designed to approximately double the baseline corticosterone levels. Corticosterone–implanted birds cached and consumed significantly more food and showed more efficient cache recovery and superior spatial memory performance compared with placebo–implanted birds. Thus, contrary to prevailing assumptions, long–term moderate elevations of corticosterone appear to enhance spatial memory in food–caching mountain chickadees. These results suggest that moderate chronic elevation of corticosterone may serve as an adaptation to unpredictable environments by facilitating feeding and food–caching behaviour and by improving cache–retrieval efficiency in food–caching birds.

Racemic Ketamine as an Alternative to Electroconvulsive Therapy for Unipolar Depression: A Randomized, Open-Label, Non-Inferiority Trial (KetECT) (via Tomas Roos ): Ekstrand J, Fattah C, Persson M, Cheng T, Nordanskog P, Åkeson J, Tingström A, Lindström M, Nordenskjöld A, Movahed RP. Racemic Ketamine as an Alternative to Electroconvulsive Therapy for Unipolar Depression:: A Randomized, Open-Label, Non-Inferiority Trial (KetECT). International Journal of Neuropsychopharmacology. 2021.

Background Ketamine has emerged as a fast-acting and powerful antidepressant, but no head to head trial has been performed, Here, ketamine is compared with electroconvulsive therapy (ECT), the most effective therapy for depression.
Methods Hospitalized patients with unipolar depression were randomized (1:1) to thrice-weekly racemic ketamine (0.5 mg/kg) infusions or ECT in a parallel, open-label, non-inferiority study. The primary outcome was remission (Montgomery Åsberg Depression Rating Scale score ≤10). Secondary outcomes included adverse events (AEs), time to remission, and relapse. Treatment sessions (maximum of 12) were administered until remission or maximal effect was achieved. Remitters were followed for 12 months after the final treatment session.
Results In total 186 inpatients were included and received treatment. Among patients receiving ECT, 63% remitted compared with 46% receiving ketamine infusions (P = .026; difference 95% CI 2%, 30%). Both ketamine and ECT required a median of 6 treatment sessions to induce remission. Distinct AEs were associated with each treatment. Serious and long-lasting AEs, including cases of persisting amnesia, were more common with ECT, while treatment-emergent AEs led to more dropouts in the ketamine group. Among remitters, 70% and 63%, with 57 and 61 median days in remission, relapsed within 12 months in the ketamine and ECT groups, respectively (P = .52).
Conclusion Remission and cumulative symptom reduction following multiple racemic ketamine infusions in severely ill patients (age 18–85 years) in an authentic clinical setting suggest that ketamine, despite being inferior to ECT, can be a safe and valuable tool in treating unipolar depression.

Beersma DG, Van den Hoofdakker RH. Can non-REM sleep be depressogenic?. Journal of affective disorders. 1992 Feb 1;24(2):101-8.

Bessone P, Rao G, Schilbach F, Schofield H, Toma M. The economic consequences of increasing sleep among the urban poor. The Quarterly Journal of Economics. 2021 Aug;136(3):1887-941.

Consensus Conference Panel:, Watson, N.F., Badr, M.S., Belenky, G., Bliwise, D.L., Buxton, O.M., Buysse, D., Dinges, D.F., Gangwisch, J., Grandner, M.A. and Kushida, C., 2015. Joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society on the recommended amount of sleep for a healthy adult: methodology and discussion. Journal of Clinical Sleep Medicine, 11(8), pp.931-952.

Eckert A, Karen S, Beck J, Brand S, Hemmeter U, Hatzinger M, Holsboer-Trachsler E. The link between sleep, stress and BDNF. European Psychiatry. 2017 Apr;41(S1):S282-.

Ekstrand J, Fattah C, Persson M, Cheng T, Nordanskog P, Åkeson J, Tingström A, Lindström M, Nordenskjöld A, Movahed RP. Racemic Ketamine as an Alternative to Electroconvulsive Therapy for Unipolar Depression:: A Randomized, Open-Label, Non-Inferiority Trial (KetECT). International Journal of Neuropsychopharmacology. 2021.

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Goldschmied JR, Rao H, Dinges D, Goel N, Detre JA, Basner M, Sheline YI, Thase ME, Gehrman PR. 0886 Recovery Sleep Significantly Decreases BDNF In Major Depression Following Therapeutic Sleep Deprivation. Sleep. 2019 Apr;42(Supplement_1):A356-.

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Lyamin OI, Kosenko PO, Korneva SM, Vyssotski AL, Mukhametov LM, Siegel JM. Fur seals suppress REM sleep for very long periods without subsequent rebound. Current Biology. 2018 Jun 18;28(12):2000-5.

Pravosudov VV. Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory. Proceedings of the Royal Society of London. Series B: Biological Sciences. 2003 Dec 22;270(1533):2599-604.

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Rahmani M, Rahmani F, Rezaei N. The brain-derived neurotrophic factor: missing link between sleep deprivation, insomnia, and depression. Neurochemical research. 2020 Feb;45(2):221-31.

Riemann, D., König, A., Hohagen, F., Kiemen, A., Voderholzer, U., Backhaus, J., Bunz, J., Wesiack, B., Hermle, L. and Berger, M., 1999. How to preserve the antidepressive effect of sleep deprivation: A comparison of sleep phase advance and sleep phase delay. European archives of psychiatry and clinical neuroscience, 249(5), pp.231-237.

Seystahl K, Könnecke H, Sürücü O, Baumann CR, Poryazova R. Development of a short sleeper phenotype after third ventriculostomy in a patient with ependymal cysts. Journal of Clinical Sleep Medicine. 2014 Feb 15;10(2):211-3.

Shen X, Wu Y, Zhang D. Nighttime sleep duration, 24-hour sleep duration and risk of all-cause mortality among adults: a meta-analysis of prospective cohort studies. Scientific Reports. 2016 Feb 22;6:21480.

Shi G, Xing L, Wu D, Bhattacharyya BJ, Jones CR, McMahon T, Chong SC, Chen JA, Coppola G, Geschwind D, Krystal A. A rare mutation of β1-adrenergic receptor affects sleep/wake behaviors. Neuron. 2019 Sep 25;103(6):1044-55.

Siegel JM. Memory Consolidation Is Similar in Waking and Sleep. Current Sleep Medicine Reports. 2021 Mar;7(1):15-8.

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Problem of Sleep Deprivation Cause and Effect Essay

Introduction.

  • What is Sleep Deprivation?

Causes of Sleep Deprivation

Effects of sleep deprivation, managing sleep deprivation, works cited.

The functioning of the human body is influenced by a number of factors, which are mainly determined by the health status of an individual. Oftentimes, people seek medication when the body deviates from its normal and usual functioning mechanisms. Through different activities and processes, the body is able to use energy and replenish itself. Sleeping is one of the activities that has a direct effect on the functioning of the body.

This sleep deprivation essay explores how the functioning of the human body is influenced by various factors, primarily determined by an individual’s health status. While most people do not understand the implications of sleep, human effectiveness solely depends on the amount of time dedicated to sleeping. However, for various reasons, people fail to get enough sleep daily, weekly, or on a regular basis.

What Is Sleep Deprivation?

This cause and effect of sleep deprivation essay defines sleep deprivation as a condition occurring among human beings when they fail to get enough sleep. Sleep deprivation is defined as a condition that occurs when human beings fail to get enough sleep. Many experts argue that sleep deficiency is widespread even though most people do not consider it to be a serious issue, which affects their (Gaine et al.). Sleep deprivation has become a major problem in the United States, with almost 47 million suffering from the condition (Wang and Xiaomin). This lack of sleep can lead to a variety of physical and mental health issues, impacting daily functioning and quality of life.

The present essay about sleep deprivation defines sleep deprivation as a condition that occurs among human beings when they fail to get enough sleep. Many experts argue that sleep deficiency is widespread even though most people do not consider it to be a serious issue that affects their lives. Sleep deprivation has become a major problem in the United States, with almost forty-seven million suffering from the condition (Wang and Xiaomin). Among other reasons, one may get insufficient sleep in a day as a result of various factors. Some people sleep at the wrong time due to busy daily schedules, while others have sleep disorders, which affect their sleeping patterns. The following segment of the paper discusses the causes of deprivation.

Sleep deprivation may occur as a result of factors that are not known to the patients. This is based on the fact that sleep deprivation may go beyond the number of hours one spends in bed. In some cases, the quality of sleep matters in determining the level of deprivation.

In this context, it is possible for one to be in bed for more than eight hours but suffer from the negative effects of sleep deprivation. Whilst this is the case, there are people who wake every morning feeling tired despite having spent a recommended number of hours in bed (Griggs et al.14367).

Sleep deprivation can be caused by medical conditions, which may include but are not limited to asthma, arthritis, muscle cramps, allergies, and muscular pain. These conditions have been classified by researchers as common medical conditions that largely contribute to most of the cases of sleep deprivation being witnessed in the United States.

Similarly, these medical conditions have a direct impact on not only the quality but also the time one takes in bed sleeping. It is worth noting that sometimes people are usually unconscious to realize that their sleep is not deep enough (Wang and Xiaomin). This also explains the reason why it is not easy for a person to recall any moment in life when he or she moved closer to waking up.

Treatment of cases like sleep apnea is important because it affects the quality of sleep without necessarily awakening the victim. This is because medical surveys have revealed fatal effects of sleep apnea, especially on the cardiovascular system. Besides these, one is likely to experience breathing difficulties caused by insufficient oxygen.

Even though the treatment of sleep deprivation is important, it has been found that some drugs used to treat patients may worsen the case or lead to poor quality of sleep. It is, therefore, necessary for the doctor to determine the best drugs to use. Discussions between doctors and victims are imperative in order to understand patients’ responses (Conroy et al. 185).

Sleep deprivation is also caused by sleep cycle disruptions, which interfere with the fourth stage of sleep. Oftentimes, these disruptions are described as night terrors, sleepwalking, and nightmares.

Though these disorders are known not to awaken a person completely, it is vital to note that they may disrupt the order of sleep cycles, forcing a person to move from the fourth stage to the first one. Victims of these disruptions require attention in order to take corrective measures.

In addition, there are known environmental factors which contribute to several cases of sleep deprivation. However, doctors argue that the impact on the environment is sometimes too minimal to be recognized by people who are affected by sleep deficiency (Gaine et al.). In other words, these factors affect the quality of sleep without necessarily arousing a person from sleep.

Common examples include extreme weather conditions, like high temperatures, noise, and poor quality of the mattress. As a result, they may contribute to a person’s awakening, depending on the intensity when one is sleeping.

Moreover, the impact of these factors may develop with time, thus affecting one’s quality of sleep. In addition, most of the environmental factors that contribute to sleep deprivation can be fixed easily without medical or professional skills. Nevertheless, the challenge is usually how to become aware of their existence.

Lastly, sleep deprivation is caused by stress and depression, which have been linked to other health disorders and complications. Together with some lifestyles in America, these factors are heavily contributing to sleep deficiency in most parts of the world. Even though they might not be acute enough to awaken an individual, their cumulative effects usually become significant.

There are countless stressors in the world that affect youths and adults. While young people could be concerned with passing exams, adults are normally preoccupied with pressure to attain certain goals in life. These conditions create a disturbed mind, which may affect a person’s ability to enjoy quality sleep.

Sleep deprivation has a host of negative effects which affect people of all ages. The commonest effect is stress. Most people who suffer from sleep deficiency are likely to experience depression frequently as compared to their counterparts who enjoy quality sleep (Conroy et al. 188). As a result, stress may lead to poor performance among students at school.

Research has revealed that students who spend very few hours in bed or experience disruptions during sleep are likely to register poor performance in their class assignments and final exams. Additionally, sleep deprivation causes inefficiency among employees.

For instance, drivers who experience this disorder are more likely to cause accidents as compared to those who are free from it (Griggs et al.14367). This is based on the fact that un-refreshed people have poor concentration and low mastery of their skills.

Besides stress and anxiety, sleep deprivation has a wide-range of health-related effects. For instance, medical experts argue that people who spend less than six hours in bed are likely to suffer from high blood pressure. Quality sleep gives the body an opportunity to rest by slowing down the rate at which it pumps blood to the rest of the body (Wang and Xiaomin).

Inadequate sleep implies that the heart has to work without its normal and recommended rest. Additionally, sleep deprivation is known to affect the immune system. People who experience this disorder end up with a weakened immune system, leaving the body prone to most illnesses. This reduced immune response accumulates and may become fatal with time.

Sleep paralysis is also a common effect of inadequate sleep. This is due to disruption of the sleep cycle. It primarily occurs when the body is aroused during the fourth stage of the sleep cycle. In this case, the body is left immobile as the mind regains consciousness. Due to this conflict, one may experience pain and hallucinations.

Based on the negative effects of sleep deprivation, there is a need to manage this disorder among Americans. Firstly, it is necessary for people to seek medical advice concerning certain factors which could be contributing to this condition, like stress and infections (Wang and Xiaomin).

Proper counseling is also vital in stabilizing a person’s mental capacity. Physical exercises are also known to relieve a person from stressful conditions, contributing to sleep deficiency. Lastly, it is essential to ensure that the environment is free from noise and has regulated weather conditions.

Sleep deprivation remains a major problem in America, affecting millions of people. As discussed above, sleep deprivation is caused by a host of factors, ranging from environmental to health-related issues. Moreover, sleep deficiency has countless effects, most of which may become fatal in cases where the disorder is chronic.

Conroy, Deirdre A., et al. “ The Effects of COVID-19 Stay-at-home Order on Sleep, Health, and Working Patterns: A Survey Study of US Health Care Workers. ” Journal of Clinical Sleep Medicine , vol. 17, no. 2, Feb. 2021, pp. 185–91.

Gaine, Marie E., et al. “ Altered Hippocampal Transcriptome Dynamics Following Sleep Deprivation. ” Molecular Brain, vol. 14, no. 1, Aug. 2021.

Griggs, Stephanie, et al. “ Socioeconomic Deprivation, Sleep Duration, and Mental Health During the First Year of the COVID-19 Pandemic. ” International Journal of Environmental Research and Public Health, vol. 19, no. 21, Nov. 2022, p. 14367.

Wang, Jun, and Xiaomin Ren. “ Association Between Sleep Duration and Sleep Disorder Data From the National Health and Nutrition Examination Survey and Stroke Among Adults in the United States .” Medical Science Monitor , vol. 28, June 2022.

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The Effect of Sleep Quality on Students’ Academic Achievement

Rostam jalali.

1 Faculty of Nursing and Midwifery, Kermanshah University of Medical Sciences, Kermanshah, Iran

Habibollah Khazaei

2 Sleep Disorders Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran

Behnam Khaledi Paveh

Zinab hayrani, lida menati.

Sleep is an inseparable part of human health and life, which is crucial in learning, practice, as well as physical and mental health. It affects the capacity of individual learning, academic performance, and neural-behavioral functions. This study aimed to determine the relationship between sleep quality and students’ academic achievement among students at Kermanshah University of Medical Sciences.

In this cross-sectional study, 102 medical students from different fields, with maximum variation sampling, completed Pittsburgh Sleep Quality Index (PSQI). For data analysis, SPSS 19 was used through which Pearson correlation test, Spearman test, and t -test were employed.

Based on the quality of sleep questionnaire scores, the results indicated no significant difference between students with high grades and those with low grades. However, there were moderate and sometimes severe sleep disturbances in both groups.

The results showed no significant difference between sleep quality and academic achievement. Nevertheless, longitudinal study should be performed to control for confounding factors.

Sleep is an inseparable part of human health and life, and is pivotal to learning and practice as well as physical and mental health. 1 Studies have suggested that insufficient sleep, increased frequency of short-term sleep, and going to sleep late and getting up early affect the learning capacity, academic performance, and neurobehavioral functions. 2 , 3 Previous studies have indicated that the quantity of sleep reported by individuals as delayed or inappropriate sleep, waking up too late, especially at weekends and daytime sleepiness is associated with compromised academic performance in children and adults. 2 Some studies have emphasized the relationship between delayed starting time of classes and academic success. 4 Reduced overnight sleep or altered sleep patterns has been associated with severe drowsiness and failure in academic success. 5 In a study, people who had enough sleep compared to their sleep-deprived individuals used innovative solutions twice as often when confronted with complex mathematical problems. 6 The chance of academic failure was as long as one or more than 1 year in students with inadequate sleep compared to those with proper sleep. 7 People who sleep less and sleep during the day are more prone to vehicle and work accidents. 8 In some studies, sleep efficiency has been considered as essential for recovery, cognitive processing, and memory integration. 9 On the other hand, lack of sleep has been associated with emotional instability and impaired concentration. 10 In this regard, students are particularly at risk of developing sleep disorders and development of the disorder among them has a negative effect on their academic performance across different grades, 11 – 13 However, there is no consensus in this case and not all studies state that sleep disorders yield a negative effect on academic performance. Eliasson (2010) believes that the time it takes to fall asleep and waking up affect academic performance more than duration of sleep does. 14 Sweileh and colleagues (2011) also believe that there is no relationship between sleep quality and academic success. 15 Similarly, it is claimed there is no relationship between the night sleep before the exam and test scores either. 16

In another study, the author believes stress from lack of sleep causes poor school performance. 17 On the other hand, in a systematic review, the authors could not establish a cause and effect relationship between sleep quality and academic performance. 2 In their meta-analysis study, Dewald and colleagues (2010) emphasized that because of the diversity of the methodology of studies, it is impossible to definitely derive a relationship between sleep quality and academic performance, and thus more longitudinal intervention studies are warranted. 1 According to different conclusions in this respect, the researchers decided to determine the relationship between sleep quality and academic performance among students at Kermanshah University of Medical Sciences.

In this cross-sectional study, through maximum variation sampling, the first three students with highest scores and three last students with lowest scores were selected, and the Pittsburgh Sleep Quality Index (PSQI) was completed for them.

The study population consisted of students of Kermanshah University of Medical Sciences. The samples were also students at each school with the highest GPA (first three high scores) and the lowest GPA (last three lowest scores). The sampling was purposeful sampling with maximum variation. The sample covered a number of disciplines in the third semester and above ( Figures 1 & 2 ). After determining the target students, the questionnaire was given to them and then returned to the researcher after completion.

An external file that holds a picture, illustration, etc.
Object name is AMEP-11-497-g0001.jpg

Abundant distribution of students by field of study.

An external file that holds a picture, illustration, etc.
Object name is AMEP-11-497-g0002.jpg

Frequency distribution of students by semester.

The data collection instruments were demographic form (including age, gender, place of residence, grade, rank in the class, discipline) and Pittsburgh Sleep Quality Index (PSQI). PSQI is a self-report questionnaire which examines the quality of sleep. It has 18 questions which are classified into seven components: the first component is the subjective sleep quality which is determined with Question 9. The second component is related to delays in falling asleep, where the score is calculated by two questions, the mean score of Question 2 and part of Question 5. The third component deals with sleep duration and is determined by Question 4. The fourth component is related to the efficiency and effectiveness of sleeping in patients. Its score is calculated via dividing the total hours of sleep by total hours in the bed multiplied by 100. Then, the fifth component deals with sleep disorders and is achieved by calculating the mean value of Question 5. The sixth component is related to hypnotic drugs and is determined based on Question 6. Finally, the seventh component captures inadequate performance throughout the day and is determined by two questions (mean scores of Questions 7 and 8). Each question is rated between 0 and 3 points where maximum score for each component is 3. The total scores range of the seven components making up the total score range from 0 to 21. Higher scores represent a lower sleep quality, where a score above 6 indicates poor sleep quality. The reliability and validity of this inventory have also been approved in Iran, where the Cronbach’s alpha coefficient of the questionnaire was 0.78 to 0.82. 18 In another study, Cronbach’s alpha for the Persian version was 0.77. In cut-off point 5, the sensitivity and specificity were 94% and 72%, and in cut-off point 6, they were 85% and 84%, respectively. 19

After collecting the questionnaires and introducing students’ demographic data to a computer using SPSS version 16, the relationship between sleep quality scores and grade point average (GPA high and low) was calculated.

The results indicated that 34 cases (33.3%) of the subjects were male. The mean age of the sample 23.10 ± 3.25, where the mean age for females was 22.46± 2.44 and for males was 24.38± 4.19. The participants in the study came from various disciplines including laboratory science, medicine, pharmacology, emergency medicine, obstetrics, radiology, operating room, health technology, and nursing.

Most students lived in dormitories (50%) and 46.1% at home, with 3.9% living in rental houses. The students' educational level ranged between the third semester and twelfth semester.

Among those participating in the study, 67 patients (65.7%) consumed coffee, 90 cases (88.2%) used tea, and 1 (1%) took a drug.

For comparing the mean scores of students and the component of sleep, Spearman test (non-normal data) was employed, where a significant correlation was observed between GPA and hours taking to fall asleep ( Table 1 ).

The Relationship Between Sleep Components and GPA in KUMS Students

Similarly, there was a relationship between sleep components and tea, coffee, hypnotic drugs, and drug ( Table 2 ).

The Relationship Between Sleep Components and Type of Drink or Drug in KUMS Students Kermanshah

On the other hand, independent t -test between Pittsburgh scores in the two groups did not show any significant differences. Nevertheless, impaired sleep quality was moderate to severe in both groups ( Table 3 ).

The Difference Between the Mean Pittsburg Scores in Two Groups (Students with High and Low GPA)

The results indicated that impaired sleep quality between the two groups was not statistically significant. Although the relationship between sleeping and academic success has been introduced in medical literature since a long time, there still no definitive answer in this case. In a meta-analysis study conducted to examine the impact of sleep quality, sleep duration, and sleepiness on adolescents’ academic performance, although all three variables were related to academic achievement (positive relationship between sleep quality and duration of sleep and negative association with sleepiness), this relationship was very trivial. 1

On the other hand, another systematic review study of descriptive studies concluded that sleep disturbance adversely affects different areas such as general health, social status, and academic performance. However, longitudinal studies are required for a more accurate examination. 20 , 21 In an another systematic review of other authors, the authors concluded that under-sleeping would have an impact on learning of some students, and could have a detrimental effect on academic achievement. 22 Further, another review study also suggests a conclusive recommendation which has to be done to modify sleep so that it can be used for academic success. 23

The present study was conducted to explore whether sleep disorder can influence academic achievement or not. Accordingly, a specific sample of accomplished or unachieved students were selected to compare the quality and quantity of sleep. However, no significant difference was between the two groups. Other studies have reached similar conclusions.

Sweileh and his colleagues in a study on 400 Palestinian students concluded that academic achievement was not correlated with sleep quality. 15 In another study on 189 medical students in Pakistan, there was no significant association between lack of sleep and test scores. 16 In this regard, there is a possibility of sleep disorder in students, and this possibility has been expressed for the lack of academic achievement, but it has not been clearly explained. 11 In another study, sleepiness during the day (not the quality and quantity of sleep) was identified as an independent predictor of academic success. 5 In a similar study again the time it takes to fall sleep and the wake-up time (not the total amount of sleep) were associated with academic success, 14 where the total amount of sleep in adolescents with a dynamic mind was not related to their academic achievement. 24 In contrast to such studies that emphasize lack of association or low association, there are other studies that have observed an inverse relationship between sleep disturbance and academic achievement. In a study on 491 first-, second-, and third-year medical students, there was a correlation between academic performance and the amount of nighttime sleep as well as daytime sleepiness. 25 In a similar study on medical students, lack of sleep at night, late going to bed, and daytime sleepiness had a negative effect on the academic performance of the students. 26 Notably, sleep disturbances are likely to yield a negative impact on academic performance, thereby causing a vicious cycle. 25 , 27 Taken together, the studies suggest that most studies have mentioned poor quality sleep among the majority of students. 3 , 26 , 27 Accordingly, concluding the relationship between common sleep disturbance and academic performance should be done with caution. The reason is that academic success can be affected by different factors including the level of family income, the evolutionary process, intake of supplements and vitamins, family size, social media dependency, addiction to social networks, and social issues. In studies these extraneous factors are not under control, thus emphasizing the fact that the presence or absence of correlation between sleep quality and academic performance should be done with caution and using longitudinal studies.

Limitations

The main limitation of this study was the small sample size, but a specific sampling method was chosen to overcome this shortcoming. Another limitation of the study was not controlling for confounding factors in the study. Based on the results of this study and similar studies, further research should be conducted with a better design.

The results indicated no significant difference between sleep quality in achieved and unachieved academic performance. Nevertheless, to conclude with more certainty, longitudinal studies should be performed to control confounding factors.

Acknowledgments

The authors of this article appreciate the collaborations of the Sleep Disorders Research Center.

Funding Statement

Funding for this research was provided by the Kermanshah University of Medical Sciences, Sleep Disorders Research Center (93026).

Data Sharing Statement

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Ethics Approval and Consent to Participate

Informed consent obtained from all participants in the study and this study conducted by the Sleep Disorders Research Center. Identity letter obtained from deputy of research and technology to collecting data. Ethics approval was received from the ethics committee of deputy of research and technology – Kermanshah University of Medical Sciences, number 93026 on 6 April 2013.

The authors declare that they have no conflict of interest.

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  • About Heart Disease
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About Sleep and Your Heart Health

  • Getting good sleep isn’t just important for your energy levels—it’s critical for your heart health, too.
  • Sleep helps your body repair itself. Getting enough good sleep also helps you function normally during the day.

Man reaching over to alarm clock

How much sleep do I need?

Most adults need at least 7 hours of sleep each night. 1 However, more than 1 in 3 American adults say they don't get the recommended amount of sleep. 2 While this may be fine for a day or two, not getting enough sleep over time can lead to serious health problems—and make certain health problems worse.

Steps to take

  • Stick to a regular sleep schedule. Go to bed at the same time each night and get up at the same time each morning, including on the weekends.
  • Get enough natural light, especially earlier in the day. Try going for a morning or lunchtime walk.
  • Get enough physical activity during the day. Try not to exercise within a few hours of bedtime.
  • Avoid artificial light, especially within a few hours of bedtime. Use a blue light filter on your computer or smartphone.
  • Don't eat or drink within a few hours of bedtime; avoid alcohol and foods high in fat or sugar in particular.
  • Keep your bedroom cool, dark, and quiet.

Work with your health care team to identify obstacles to good sleep, including other medical conditions.

What health conditions are linked to a lack of sleep?

Adults who sleep fewer than 7 hours each night are more likely to say they have had health problems, including heart attack, asthma, and depression. 3 Some of these health problems raise the risk for heart disease, heart attack, and stroke. These health problems include:

High blood pressure. During normal sleep, your blood pressure goes down. Having sleep problems means your blood pressure stays higher for a longer period of time. 4 High blood pressure is one of the leading risks for heart disease and stroke. About 75 million Americans—1 in 3 adults—have high blood pressure. 5

Type 2 diabetes. Diabetes is a disease that causes sugar to build up in your blood, a condition that can damage your blood vessels. Some studies show that getting enough good sleep may help people improve blood sugar control. 6

Obesity. Lack of sleep can lead to unhealthy weight gain. This is especially true for children and adolescents, who need more sleep than adults. Not getting enough sleep may affect a part of the brain that controls hunger. 6

What sleep conditions can hurt my heart health?

Over time, sleep problems can hurt your heart health.

Sleep apnea happens when your airway gets blocked repeatedly during sleep, causing you to stop breathing for short amounts of time. Sleep apnea can be caused by certain health problems, such as obesity and heart failure.

Sleep apnea affects how much oxygen your body gets while you sleep and increases the risk for many health problems, including high blood pressure, heart attack, and stroke. It is more common among Black, Hispanic, and Native American adults than among White adults. 7

Insomnia refers to trouble falling sleep, staying asleep, or both. As many as 1 in 2 adults experiences short-term insomnia at some point, and 1 in 10 may have long-lasting insomnia. 8 Insomnia is linked to high blood pressure and heart disease. Over time, poor sleep can also lead to unhealthy habits that can hurt your heart, including higher stress levels, less motivation to be physically active, and unhealthy food choices.

  • High Blood Pressure
  • Sleep and Sleep Disorders

National Heart, Lung, and Blood Institute (NHLBI)

  • Sleep Science and Sleep Disorders
  • Centers for Disease Control and Prevention. How much sleep do I need? Accessed September 8, 2020. https://www.cdc.gov/sleep/about_sleep/how_much_sleep.html
  • Liu Y, Wheaton AG, Chapman DP, Cunningham TJ, Lu H, Croft JB. Prevalence of healthy sleep duration among adults—United States, 2014 . MMWR Morb Mortal Wkly Rep . 2016;65(6):137–141.
  • Centers for Disease Control and Prevention. Data and statistics: short sleep duration among US adults. Accessed September 8, 2020. https://www.cdc.gov/sleep/data_statistics.html
  • Calhoun DA, Harding SM. Sleep and hypertension. Chest . 2010;138(2):434–443.
  • Million Hearts. High blood pressure. Accessed February 7, 2024. https://millionhearts.hhs.gov/data-reports/hypertension-prevalence.html
  • Centers for Disease Control and Prevention. Sleep and chronic disease. Accessed September 8, 2020. https://www.cdc.gov/sleep/about_sleep/chronic_disease.html
  • National Heart, Lung, and Blood Institute. What is sleep apnea? Accessed April 24, 2024. https://www.nhlbi.nih.gov/health-topics/sleep-apnea
  • Sateia MJ, Buysse DJ, Krystal AD, Neubauer DN, Heald JL. Clinical practice guideline for the pharmacologic treatment of chronic insomnia in adults: an American Academy of Sleep Medicine clinical practice guideline . J Clin Sleep Med . 2017;13(2):307–349.

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COMMENTS

  1. Why sleep is important

    Sleep is essential for a person's health and wellbeing, according to the National Sleep Foundation (NSF). Yet millions of people do not get enough sleep and many suffer from lack of sleep. For example, surveys conducted by the NSF (1999-2004) reveal that at least 40 million Americans suffer from over 70 different sleep disorders and 60 percent of adults report having sleep problems a few ...

  2. Sleep is essential to health: an American Academy of Sleep Medicine

    INTRODUCTION. Sleep is vital for health and well-being in children, adolescents, and adults. 1-3 Healthy sleep is important for cognitive functioning, mood, mental health, and cardiovascular, cerebrovascular, and metabolic health. 4 Adequate quantity and quality of sleep also play a role in reducing the risk of accidents and injuries caused by sleepiness and fatigue, including workplace ...

  3. The Extraordinary Importance of Sleep

    Primarily used for sleep-onset insomnia; short-acting; no short-term usage restriction. Orexin Receptor Antagonist. Suvorexant. 5-mg, 10-mg, 15-mg, and 20-mg tablets. Indicated for the treatment of insomnia characterized by difficulties with sleep onset and/or sleep maintenance. Lowest effective dose should be used.

  4. Importance of Sleep Essay

    Long Essay on Importance of Sleep 500 Words in English. Long Essay on Importance of Computer is usually given to classes 7, 8, 9, and 10. Introduction. Sleep is one of the most essential parts of our lives; still, most of us neglect it as though there's nothing wrong with that.

  5. Good Sleep for Good Health

    It can make getting a good night's sleep on a regular basis seem like a dream. But sleep is as important for good health as diet and exercise. Good sleep improves your brain performance, mood, and health. Not getting enough quality sleep regularly raises the risk of many diseases and disorders. These range from heart disease and stroke to ...

  6. Sleep Quality, Mental and Physical Health: A Differential Relationship

    1. Introduction. Sleep is an essential and universal function for humans [].Sleep is now considered one of the three basic pillars of health together with diet and exercise [].Poor sleep quality has a negative impact in different areas related to physical health such as type 2 diabetes [], hypertension [], chronic pain [] and higher levels of body mass index [6,7] among other adverse consequences.

  7. Why Do We Need Sleep?

    Why Getting Enough Sleep Is Important. Sleep is an essential function that allows your body and mind to recharge, leaving you refreshed and alert when you wake up. Healthy sleep also helps the body remain healthy and stave off diseases. Without enough sleep, the brain cannot function properly, impairing your abilities to concentrate, think ...

  8. Why Sleep Is So Important

    Sleep Reduces Stress. Sleep is a powerful stress reliever. It improves concentration, regulates mood, and sharpens judgment and decision-making. A lack of sleep not only reduces mental clarity but the ability to cope with stressful situations. This is due, in part, to changes in cortisol levels.

  9. Why are we so sleep deprived, and why does it matter?

    When we are sleep deprived, our bodies become more aroused through an enhanced sympathetic nervous system, known as "fight or flight.". There is a greater propensity for increased blood ...

  10. Sleep Science: In the Era of Screens, Rest is Crucial

    Around 350 B.C., Aristotle wrote an essay, "On Sleep and Sleeplessness," wondering just what we were doing and why. For the next 2,300 years no one had a good answer. ... REM sleep is ruled by ...

  11. How Sleep Works

    During sleep, your body is working to support healthy brain function and maintain your physical health. In children and teens, sleep also helps support growth and development. Getting inadequate sleep over time can raise your risk for chronic (long-term) health problems. It can also affect how well you think, react, work, learn, and get along ...

  12. PDF Pathways to Sleep I: An Introduction

    us) about sleep and provide guidance toward getting a good night of sleep. The first of these essays introduces the topic of sleep and provides important general information about the nature of sleep. The next four essays provide information about the pathways associated with the four components of high-quality sleep.

  13. 4.2 Sleep and Why We Sleep

    Another theory regarding why we sleep involves sleep's importance for cognitive function and memory formation (Rattenborg, Lesku, Martinez-Gonzalez, & Lima, 2007). Indeed, we know sleep deprivation results in disruptions in cognition and memory deficits (Brown, 2012), leading to impairments in our abilities to maintain attention, make ...

  14. Why is sleep important? 9 reasons for getting a good night's rest

    4. Greater athletic performance. Adults need between 7 and 9 hours of sleep a night, but recent studies have suggested that athletes may need more. Sleep is important for athletes and people ...

  15. The Global Problem of Insufficient Sleep and Its Serious Public Health

    Insufficient sleep is a pervasive and prominent problem in the modern 24-h society. A considerable body of evidence suggests that insufficient sleep causes hosts of adverse medical and mental dysfunctions. An extensive literature search was done in all the major databases for "insufficient sleep" and "public health implications" in this ...

  16. Sleep

    Sleep is the balm that soothes and restores after a long day. Sleep is largely driven by the body's internal clock, which takes cues from external elements such as sunlight and temperature. The ...

  17. Growing concerns about sleep

    Decades of research have linked chronic sleep deprivation to an increased risk for obesity, heart disease, Type 2 diabetes, and problems with immune function (" Sleep and Sleep Disorders ," Centers for Disease Control and Prevention). Sleeping more or less than recommended—typically 7 to 9 hours a night—is a significant predictor of ...

  18. The Role of Sleep in Humans' Well-Being Essay

    Introduction. Sleep is considered one of the most important parts of any individual's life. Some researchers emphasize the usefulness of sleep for productivity, while others focus on its impact on people's health. The present paper will offer several different opinions on the role that sleep plays in the satisfaction of humans' well-being.

  19. Sleep Loss and Emotion: A Systematic Review and Meta-Analysis

    Included studies had to 1) use healthy samples without psychiatric, sleep or medical disorders that impact sleep/emotions, 2) experimentally manipulate nighttime sleep deprivation, restriction or fragmentation, 3) have an adequate control/baseline condition, 4) assess an emotion-related dependent variable after the sleep manipulation.

  20. Essay on Importance of Sleep

    500 Words Essay on Importance of Sleep The Importance of Sleep: An Underrated Aspect of Health. Sleep, often overlooked, is a crucial aspect of our overall health and well-being. In our fast-paced society, sleep is frequently sacrificed for more seemingly productive activities, however, this neglect can have serious health consequences. ...

  21. Theses on Sleep

    Summary: In this essay, I question some of the consensus beliefs about sleep, such as the need for at least 7 hours of sleep for adults, harmfulness of acute sleep deprivation, and harmfulness of long-term sleep deprivation and our inability to adapt to it. It appears that the evidence for all of these beliefs is much weaker than sleep scientists and public health experts want us to believe.

  22. 127 Sleep Topics for Research Papers and Essays

    Sleep Habits and Its Impact on Human Mind Activity. The researchers paid attention to the quality of sleep and mentioned such characteristics as the time of going to bed and waking up, the duration, and quality of sleep. We will write. a custom essay specifically for you by our professional experts.

  23. Problem of Sleep Deprivation

    This sleep deprivation essay explores how the functioning of the human body is influenced by various factors, primarily determined by an individual's health status. While most people do not understand the implications of sleep, human effectiveness solely depends on the amount of time dedicated to sleeping. However, for various reasons, people ...

  24. The Effect of Sleep Quality on Students' Academic Achievement

    Background. Sleep is an inseparable part of human health and life, and is pivotal to learning and practice as well as physical and mental health. 1 Studies have suggested that insufficient sleep, increased frequency of short-term sleep, and going to sleep late and getting up early affect the learning capacity, academic performance, and neurobehavioral functions. 2, 3 Previous studies have ...

  25. Essay on why academics need to get enough sleep

    Well, maybe it you get a couple extra hours of sleep tonight your 6 hours of grading will, in a more mentally rested state, really only be 4 or 5 hours of grading. Maybe even less. We all need sleep. To lead the life of the mind, one requires sufficient rest, writes Nate Kreuter.

  26. About Sleep and Your Heart Health

    During normal sleep, your blood pressure goes down. Having sleep problems means your blood pressure stays higher for a longer period of time. 4 High blood pressure is one of the leading risks for heart disease and stroke. About 75 million Americans—1 in 3 adults—have high blood pressure. 5. Type 2 diabetes.