GOOD HEALTH by YOURSELF Sleeping Well for Good Health
Preface Sleep is an essential biological process, vital for our daily functioning. Sleep is a period where the body and mind relax and recharge, the repair mechanisms kick in, and the healing takes place, hence sleep is important for our physical, mental and emotional health. Lack of sleep can impair the body’s ability to concentrate, think clearly and process memories. Improper sleep is also associated with various physical and mental health disorders. Most adults need about 7-9 hours of nightly sleep. However, statistics suggests that about 67% of adults have sleep disturbances at least once every night. This can be attributed to day-to-day stress, improper work timings, disturbance in the sleep environment, and certain medical conditions. Individuals who experience sleep disruptions for a prolonged period must seek professional help to improve their sleep quality. Good sleep hygiene, relaxation techniques, regular physical activity, and a healthy diet can help you sleep well. Sleep health is of utmost importance for our overall well-being, and we should take a step forward to get a good quality sleep. z z z
Table of Contents Understanding sleep · What is sleep? · Types of sleep · Physiological factors that control sleep · Sleep problems · Sleep quality - How good is your sleep and how to know it? - Measures to improve your sleep quality Sleep deprivation and sleep disorders · Sleep disorders · Proactive measures to prevent sleep disorders · Sleep inconsistency: Effect on physical and mental functioning · Sleep and its effect on immunity · Sleep and its effect on mental health · Sleep apnea - How does sleep apnea affect health? - What are the available solutions? 01 02
01 Understanding sleep What is sleep? Types of Sleep We all have a vague idea of what sleep is – sleep is a complex biological process, where one is partially unconscious, but the brain and body functions are still active. It helps your body to rest, restore energy, process new information and stay healthy. Getting enough quality sleep is essential for survival, just like food and water.1-3 Did you know? An individual spends one-quarter to one-third of his/her lifespan sleeping!4 Over a period of sleep, there are two different types of sleep - Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM). The NREM sleep is composed of three stages. Sleep begins with a short period of stage 1 NREM, progressing through stage 2, and 3, and finally to REM. But an individual does not remain in the REM sleep for the rest of the night, but cycles between stages of NREM and REM.4-6 The amount of sleep occurring in each stage changes with age. And each type of sleep and stages, affects the brain differently.5 It is marked by a reduction of physiological activity as the bodily functions slow down. During NREM sleep, the electrical activity in the brain slows down, the growth hormone secretion occurs, and muscle activity, heart rate, respiration, and oxygen consumption decreases. The three stages of NREM are differentiated based on the depth of sleep, or the degree of disconnection between sensory and motor functions.7 NREM sleep:
In this stage, heartbeat, breathing, eye movements and brain waves begin to slow down, and the muscles start to relax. It lasts for less than 10 minutes.7 This stage is also a period of light sleep, where the heartbeat and breathing continue to slow down and the muscles relax further. Most adults spend about 50% of their entire night’s sleep in this stage 2.5,7 In the final stage of NREM sleep, the heartbeat and breathing will slow to their lowest levels, and the muscles are extremely relaxed. This stage lasts about 40 minutes and helps the body to repair and regenerate tissues. The first NREM-REM cycle lasts for about 70 to 100 minutes, whereas the second or following cycles last longer – approx. 90 to 120 minutes.6 It is marked by intense brain activity. As one enters REM sleep, the eyes move rapidly with the eyelids closed, the breath rate increases, the body becomes temporarily paralyzed as one dreams and the brain waves are similar to those during wakefulness.4-7 REM sleep Stage 1 Stage 2 Stage 3 Total Sleep Duration REM Sleep, 20-25% NREM Sleep, 75- 80%
Physiological Factors that Control Sleep The human body has two main systems that regulate sleep – the sleep-wake homeostasis and the circadian alerting system. This is the body’s self-regulating process which builds pressure to sleep based on how long you have been awake; hence, the longer you are awake, the sleepier you feel. It also causes you to sleep more after a period of sleep deprivation. 3,4,6,8 This comprises of the circadian rhythms, which refer to the daily patterns in physiology and behavior. These rhythms are a part of the body’s biological clock (neural structures located in the hypothalamus), which is based on roughly 24-hour day, and control various biological processes, including the sleep-wake cycle. The biological clock responds to light cues and encourages wakefulness during the day and sleepiness at night. It signals to increase hormone melatonin production at night, and stopping it during the day, when it senses light.3,4,6,8 Sleep-wake homeostasis: Circadian alerting system: Individuals with total blindness usually have trouble sleeping, as they cannot detect and respond to the light cues.4
Sleep problems are conditions that can hamper sleep or prevent you from getting a restful sleep. This can cause daytime sleepiness and other problems.8-12 Most people have trouble in sleeping from time to time, due to stress, travel, or other temporary disturbances to the normal routine. However, you may have a sleep disorder, if you experience: Difficulty in sleeping regularly Tiredness during the day, even if you have slept for seven hours Decreased ability to perform daily activities Let’s take a look at some of the sleep problems. Sleep Problems There are nights when you find it hard to fall asleep; you may turn and toss on your bed, hoping to fall asleep anytime soon. This can be caused due to a health condition, stress, coffee intake, jet lag, etc. But if you have such problems regularly, you may have insomnia. Some signs of insomnia include:8-12 Occasional sleep problems usually get resolved within a month with enough rest. In case you think you may be experiencing insomnia, you should visit a doctor. • Inability to sleep when tired • Not getting enough sleep to feel well-rested and refreshed • Experiencing restless sleep and exhaustion after waking up • Inability to concentrate • Having headaches, tensed muscles, and gastrointestinal distress. Inability to sleep
Inability to go back to sleep after waking up:13-16 Can supplements help with sleep problems?18 Light sleeping:17 Sometimes you may wake up in the middle of the night; these mini-awakenings are common, many of us wake up for up to 20 times an hour, without even noticing them. Most people have observable wake-ups for about two or three per night. But some of you can struggle to go back to sleep for at least 20 – 30 minutes. Such fragmented sleep can affect your sleep quality and quantity, causing daytime sleepiness or sluggishness. Experts call this type of inability to sleep as ‘sleep maintenance insomnia’. Many individuals wake up due to a disturbing noise, light coming into their room, or other environmental factors. Symptoms of health conditions like cough due to a lung disease, heartburn due to gastroesophageal reflux diseases, or other conditions can make it difficult to fall asleep. Thus, identifying what is waking you up in the night, and addressing the issue can help you sleep better. Some vitamins and supplements which can be obtained via food and drinks, can be helpful to manage sleep problems. There are some natural remedies as well, but their use is not supported with sufficient scientific evidence. The vitamins and supplements that can help you sleep better include: Consult your doctor before consuming any of these supplements. Individuals who wake up due to small disturbances in their sleep environment, may be experiencing light sleeping. These disturbances can be noise, lights outside their window or room, or their partner shifting positions in the bed. Such factors that are out of control can disrupt sleep and makes it difficult for a person to get a good night’s sleep. Disturbed sleep or poor quality of sleep can increase your stress, affect memory and concentration, and increase sensitivity to pain. It can also be associated with long-term conditions like hypertension, diabetes, obesity, cardiovascular diseases, etc. There are several ways light sleepers can get enough sleep. This includes stress reduction techniques, following good sleep hygiene, and blocking noise and light. Chamomile tea Valerian herb Melatonin Magnesium glycinate or magnesium citrate
Sleep quality refers to how well you are sleeping, or whether your sleep is restful and restorative. The quality of your sleep ensures physical, mental and emotional benefits. Measuring the quality of sleep is a little more complicated than measuring the sleep quantity (which refers to the duration of sleep). The following four aspects are usually assessed to measure sleep quality: Sleep Quality • Falling asleep within 30 minutes or less after getting into bed • Sleeping through the night, not waking up more than once • Falling back asleep within 20 minutes, if you wake up • Feeling rested, restored and energized the next morning A good sleep is defined by: Aspects assessed Description Indications for good sleep Sleep latency How long it takes to fall asleep after going to bed Sleeping within 30 minutes or less Sleep waking How often you wake up during the night Not waking up at all or once Wakefulness How many minutes you spend awake during the night after you first go to sleep 20 minutes or less of wakefulness Sleep efficiency Amount of time you spend actually sleeping 85 percent or more Sleep satisfaction is different from sleep quality. The former is a more subjective opinion of how you feel about the sleep you are getting.19
Measures to improve your sleep quality Good sleep quality can be ensured by maintaining sleep hygiene, which is all about practicing good habits to sleep well consistently, as listed below.20,21 Stop watching television and using phone or computer at least 30 minutes before bedtime Keep your bedroom dark, quiet, and cool Go to bed and wake up at the same time every day Do not eat a large meal before bedtime Schedule your sleep time to get at least 7 – 8 hours of sleep Engage in relaxing activities before bed (journaling, listening to audiobook or a warm bath) Avoid drinking alcohol within three hours before bedtime
Do not have caffeinated drinks five hours before bedtime Exercise regularly and maintain a healthy diet Avoid drinking alcohol within three hours before bedtime Get exposed to sunlight in the morning for 15-30 minutes
02 Sleep Deprivation & Sleep Disorders Sleep disorders Common sleep disorders9,12,22-24 Sleep disorder is a rare condition that involve problems with the quality, timing, and duration of sleep. This can impact a person’s ability to properly function during the daytime. These disorders are usually associated with medical condition or mental health condition, like anxiety, depression, or cognitive disorders. Sleep disorders can also contribute to other medical problems.9,12,22-24 It is the difficulty in falling asleep or staying asleep throughout the night, accompanied with daytime impairments associated with sleep troubles. It is a type of sleep movement disorder, which causes an intense uncomfortable sensation and irresistible urge to move the legs while you try to fall asleep. It is characterized by abnormal breathing patterns during sleep, such as reduction or pauses in breathing for brief periods. These may cause the person to wake up periodically and reduce sleep quality, but the patient may not be aware of the abnormal breathing. It is a neurological condition characterized by excessive daytime sleepiness and uncontrollable, intermittent episodes of falling asleep during the daytime. Sleep apnea: Insomnia: Restless legs syndrome (RLS): Narcolepsy: Some of the common and uncommon disorders are discussed here.
Uncommon sleep disorders These are a group of disorders that occur due to an alteration to the body’s internal clock or a misalignment between this clock and the external environment. This condition is characterized by sudden body movements and vocalizations while sleeping, when a person experiences vivid dreams during REM stage. During a night terror, a person will show signs of panic while sleeping, such as screaming, kicking, or flailing, usually accompanied by rapid breathing and increased heart rate, flushing of the skin, sweating, muscle tension and dilation of pupils It is a potentially serious condition where the individual experiences persistent fatigue for longer than six months, which does not get better with rest. Night terrors:27 Circadian rhythm sleep disorders:27 REM sleep behavior disorder:26 Chronic fatigue syndrome:28
Proactive measures to prevent sleep disorders The preventive measure for sleep disorders mainly involves practicing good sleep habits and ensuring you get a good night’s sleep. Apart from the measures mentioned in the previous section (Measures to improve sleep quality) the following strategies can help prevent sleep disorders:9,29 Avoid going to bed with negative thoughts/ mindset Limit your daytime naps to 30 minutes and before 3 pm Exercise at least 20 to 30 minutes each day Avoid exercising within 5 to 6 hours before going to bed Use your bed only for sleeping and having intimate relations Write your thoughts down before, and go to bed with a clear mind
Sleep inconsistency: Effect on Physical and Mental Functioning30,31 Sleep inconsistency refers to variability in sleep patterns from night-to-night. This can affect the physical, mental, behavior and cognitive functioning. Sleep inconsistency and disruption in the circadian rhythm may lead to inflammation. Inflammation is a natural response to a disease or illness. Poor sleep impacts health outcomes through various inflammatory responses (swelling or inflammation), which are indicated by certain markers (C-reactive protein (CRP)). The higher these markers present in the body, the poorer the sleep. Waking from sleep causes short-term (acute) inflammation; however, during extended period of awakening, both pro-inflammatory and anti-inflammatory cytokines (type or proteins released by the immune system) are released. The anti-inflammatory mechanisms after prolonged awakenings may represent a compensatory mechanism to disrupted circadian rhythms, thus leading to greater inflammation overall. When the inflammation does not decrease over a period of time, it can contribute to the development of heart disease, diabetes, stroke, cancer, and Alzheimer’s disease. Sleep inconsistency has also found to be associated with greater circulating inflammatory markers IL-6 and Tumor Necrosis Factor-alpha. The high levels of CRP are also altered in conditions like rheumatoid arthritis and end-stage renal disease. This further supports the statement “sleep inconsistency and its associated inflammation can act as a ripening ground for other diseases and dysfunctions”. Waking from sleep causes acute inflammation Prolonged inflammation triggers proinflammatory and anti-inflammatory responses Anti-inflammatory mechanisms compensate disrupted circadian rhythms Greater inflammation overall
Sleep and its Effect on Immunity32 The relationship between sleep and the immune system is bidirectional. Research indicates that sleep, an important period of bodily rest, helps to strengthen our immune system. During sleep, certain components of the immune system increase. Analysis of these components suggests that they strengthen the body’s acquired immunity. Sleep also helps strengthen immune memory; in other words, it helps the immune system to remember how to recognize and react to dangerous infectious agents. Although scientists are unable to explain why this occurs during sleep, several factors may be involved: While sleeping, breathing and muscle activity slows down. This extra energy is directed towards the critical tasks to be performed by the immune system. There is a possibility that inflammation occurring during sleep can harm the physical and mental performance if it occurs when awake. Hence the body has evolved so that these processes unfold during sleep. Melatonin, a hormone produced at night, helps to counteract stress which can be associated with inflammation during sleep. Research also suggests that sleep improves the effectiveness of vaccines. Disruption of sleep is associated with severe allergic reactions. On the other hand, infections trigger various immune responses, including sleepiness and lack of energy. In addition, the time spent in certain sleep changes during infection; more time is spent in stage 3 sleep or deep sleep. This stage involves slowing certain body functions, allowing the immune system to use more energy to fight infection. This energy is also directed to mount a high fever response, another immune response to infection. Moreover, during infection, REM sleep is almost abolished to facilitate shivering to release heat and maintaining a fever, which would not be possible because of muscle paralysis in REM sleep.
Sleep and its Effect on Mental Health33-35 Sleep and mental health have a very close relationship. Poor sleep can have a negative impact on your mental health, and a mental health condition can affect your sleep quality and quantity. Brain activity during sleep has significant effects on emotional and mental well-being. Each sleep stage is associated with increased or decreased activities in different parts of the brain, allowing better learning, thinking and memory. Lack of REM sleep is harmful to the consolidation of positive emotional content, which can influence mood and emotional reactivity. Conversely, mental health conditions or disorders make it difficult to sleep well. Many individuals diagnosed with depression find it harder to sleep at night, and experience excessive daytime sleepiness. Worry and fear associated with anxiety disorder contribute to racing of the mind (hyperarousal state), which leads to insomnia. Sleep and mental health are complex problems, which are affected by several factors. Owing to their close association, it can be inferred that improving sleep can have a beneficial impact on mental health and can be a component of treating many psychiatric disorders.
How does sleep apnea affect health? There are two main types of sleep apnea:36,37 Obstructive sleep apnea: This is a more common type; it is characterized by relaxation of the throat muscles, which causes partial or complete airway blockage during sleep. Central sleep apnea: This occurs when your brain does not send signal to the muscles to breathe. This type is related to the function of central nervous system, particularly the instability in the respiratory control center. Sleep apnea affects oxygen levels in the body and reduces sleep quality. Untreated sleep apnea can impair work performance, cause work related accidents and motor vehicle crashes. It can also cause a number of health problems:36-38 Decrease in oxygen levels can increase blood pressure and strain the cardiovascular system. Obstructive sleep apnea increases the risk of hypertension, recurrent heart attack, stroke, abnormal heartbeats, and even sudden death. Sleep apnea increases your risk of developing insulin resistance and type 2 diabetes. Cardiovascular problems: Type 2 diabetes: Sleep apnea Sleep apnea is a serious sleep disorder in which a person’s breathing repeatedly stops and starts during sleep. You may have sleep apnea if:36 You snore loudly Feel tired even after sleeping the entire night Gasping for air during sleep Waking up with a dry mouth Morning headache Irritable mood Difficulty staying asleep Excessive daytime sleepiness Difficulty concentrating
Individuals with sleep apnea have increased probability of abnormal results on liver function tests; their livers are more likely to show signs of scarring (nonalcoholic fatty liver disease). Individuals with obstructive sleep apnea can have problems with certain medications and general anesthesia. Moreover, people with sleep apnea are at increased risk of complications after a major surgery, due to breathing problems, particularly when sedated and lying on their backs. Inform your doctor about your sleep apnea before having surgery. Liver problems: Complications with medications and surgery: What are the available solutions?36-38 For mild cases of sleep apnea, these conservative treatments can help: In case of moderate to severe sleep apnea, the following therapies are useful: Continuous positive airway pressure (CPAP): This is a machine that delivers a high air pressure through a mask while you sleep. The pressure is higher than that of the surrounding air, which helps to keep your upper airway passages open, thereby preventing apnea and snoring. Weight loss, even 10% can be beneficial Avoid the use of alcohol and certain sleeping pills Use of a wedge pillow or other devices to help sleep on side, rather than on the back Use of nasal sprays or breathing strips in people with sinus problems or nasal congestion Other airway pressure devices: CPAP is uncomfortable for some people; for them other devices such as auto-CPAP or bi-level positive airway pressure (BPAP) also are available. Oral appliances: Some oral appliances are designed to open your throat by bringing the lower jaw forward. Although these appliances are less effective than CPAP, they are easier to use and are effective for mild obstructive sleep apnea. Adaptive servo-ventilation (ASV): This airflow device learns your normal breathing pattern, stores the information in a built-in computer, and uses pressure to normalize your breathing pattern after you fall asleep. In case of central sleep apnea, supplemental oxygen can be delivered to the lungs with the use of various devices. If central sleep apnea is caused by an underlying heart or neuromuscular disorders, treating them might also help.
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