Energy drinks and sleep
Caffeinated soft drinks are very popular with young people today. Studies have shown that caffeine has a detrimental effect on sleep, but caffeine is much longer in the blood than people realize and it both delays sleep and reduces the quality of sleep. In this video, Erna Sif Arnardóttir and Ingibjörg Gunnarsdóttir review the effects of caffinated energy drinks on sleep.
Tips for helping children and adolescents with sleep problems
Sleep is especially important for children and adolescents, but research has shown that a large proportion of Icelandic children and adolescents are not getting enough sleep. If parents have children or adolescents who are struggling with sleep problems, it is good to be able to resort to general sleep advice. In this video, Erna Sif Arnardóttir, research specialist at RU, discusses tips for improving sleep.
Children and adolescents on a reversal – the importance of nutrition and sleep for young Icelanders.
Erna Sif Arnardóttir, PhD at the University of Iceland School of Medicine, and Ingibjörg Gunnarsdóttir, Professor at the University’s Faculty of Food and Nutrition, discuss the importance of sleep and nutrition for children and young people and the interrelationships between these factors.
The event is part of the University of Iceland’s lecture series, Best for children. The meeting was in the lecture hall of Veraldar – Vigdís’ house on 9 May 2018.
Jet lag occurs when we travel between time zones, disrupting our circadian rhythm. The primary symptoms include fatigue, difficulty concentrating, stomach problems, mild sickness, and trouble falling asleep in the evening.
The circadian rhythm, or the body clock, operates on a roughly 24-hour schedule and affects many aspects of our body. These include hunger, digestion, body temperature, hormones, and urine production. However, our body clock’s most significant impact is regarding our sleep schedule.
When it gets dark, we start to get sleepy, and in the same way, we find it easier to wake up once the sun has risen. Our body clock is, therefore, affected by brightness. Even so, these adjustments take time, so when travelling between time zones, our body clock will remain the same despite external conditions changing. Our body clock is no longer in sync with the local time.
Jet lag is a temporary state. Typically, it takes our body one day to recover for every time zone passed. For example, if we fly from New York to London (4-hour difference), it will take us about four days to recover. The severity of the jet lag depends on how many time zones were passed and in which direction. It is easier to adjust when flying from the east to the west (going back a few time zones), as staying up longer comes more naturally for us than going too early to sleep.
For most people, jet lag is nothing of concern. Nevertheless, for people who fly very regularly, such as pilots and flight attendants, jet lag can cause problems. Older adults are also more likely to have severe jet lag.
To reduce the symptoms, it is recommended to minimize caffeine- and alcohol consumption, spend time outdoors, exercise, and eat and drink in accordance with the current local time. Melatonin intake can also be helpful but should only be carried out under the supervision of a doctor.
References and further information can be found on the American Academy of Sleep Medicine’s website:
http://sleepeducation.org/essentials-in-sleep/jet-lag/overview
https://www.visindavefur.is/svar.php?id=10612
Sleepwalking is a sleep disorder, causing you to arise and perform various, everyday actions, while you are still asleep.
During sleepwalking, the eyes are usually wide open but have a distant, glassy look to them. The subject may sit up in its bed, walk around, talk, and perform simple actions, such as getting dressed, urinating, or eating. Often, these actions are not performed correctly, the subject may urinate in a trash can, dress incorrectly or go out the window. The actions can also be more complicated, some sleepwalkers have even managed to drive a car a long distance.
Sleep can be divided into REM-sleep (rapid eye movement sleep) and NREM-sleep (non-rapid eye movement sleep). REM-sleep is usually where our dreams take place, while NREM-sleep is where our deep sleep occurs. Contrary to what most people may think, sleepwalking does not occur in the REM-stage, but the NREM-stage. Therefore, people are usually not dreaming while they sleep-walk. Generally, they have no memory of sleepwalking and are often unaware of it.
Sleepwalkers can be very hard to wake up and are often confused if they wake up during an episode. Usually, it is not considered dangerous to wake a sleepwalker. It can even be necessary if the subject, or its partner, is in danger. Some sleepwalkers, men especially, may express violent behavior when awoken.
Sleepwalking is much more common among children than adults. The behavior will usually fade over time and can be considered a normal part of a child’s sleeping pattern. Although uncertain, this might be since we get way more NREM-sleep during our childhood, increasing our chances of sleepwalking. Sleepwalking is also more prone to occur during the first third of a night’s sleep, where most of our NREM-sleep takes place.
The frequency of the episodes varies between individuals. Some people rarely have episodes, while others have a few episodes in one night, even many nights in a row. Children, who sleepwalk, will often talk in their sleep, have sleep terrors, and suffer from bedwetting.
Sleepwalking is often associated with an irregular sleep schedule and stressful environment. It is recommended to keep a consistent sleep schedule and, in some cases, consult a doctor.
References and further information can be found on the American Academy of Sleep Medicine‘s website:
http://sleepeducation.org/sleep-disorders-by-category/parasomnias/sleepwalking/overview-facts
https://www.sleepfoundation.org/articles/sleepwalking
REM sleep behavior disorder (RBD) is a sleep disorder that causes you to act out your dreams while sleeping.
REM-sleep (rapid eye movement sleep) is the stage of sleep where dreaming usually occurs. Normally, when we sleep, our brain sends out signals, ordering our muscles to relax. This prevents us from being able to move our muscles while sleeping, our muscles are in a temporary state of paralysis. However, this seems to go awry in people with RBD, causing them to move during sleep. Their dreams are often vivid and even violent.
Over time, RBD tends to get worse. This can result in injury, affecting either the person dreaming or its partner. The actions of a person with RBD resemble its actions in the current dream in detail. Common actions include screaming, kicking, punching, jumping, and running. Usually, the subject’s eyes are closed the whole time, separating this disorder from sleepwalking, to which it is often confused with.
As REM-sleep stages occur approximately every 90 minutes during sleep, REM behavior usually takes place at least one and a half-hour after the subject falls asleep. The episodes can occur up to four times in a single night but are also known to happen less frequently, such as weekly or monthly.
RBD can appear at any age, although it is the most likely to appear after the age of 50. It is more common among men and people who suffer from Parkinson’s disease or MSA (Multiple system atrophy). RBD does usually not cause daytime sleepiness, but other sleep disorders, such as sleep apnea, may follow and cause such symptoms.
It is recommended that people who suffer from RBD keep a consistent sleep schedule and avoid consuming alcohol before sleep, as it can increase the symptoms.
As the symptoms of RBD usually get worse over time, you might want to see a doctor if you think you suffer from the disorder.
References and further information can be found on the American Academy of Sleep Medicine’s website:
http://sleepeducation.org/sleep-disorders-by-category/parasomnias/rem-sleep-behavior-disorder
We spend about one–third of our lives sleeping. Sleep invigorates our body and mind, as well as supporting our immune- and nervous system. Without sleep, we would be unable to process our thoughts and emotions and keep track of our memories. Insufficient sleep increases the risk of health problems drastically. Those include depression, cardiovascular disease, high blood pressure, diabetes, and obesity. Sleep is, therefore, an indispensable part of our life, a foundation of both physical and mental health.
Even though most people may be aware of this to some extent, few people bother to get enough sleep. School and work performance are greatly affected by lack of sleep, and our mental health suffers even more. Sadly, many have become accustomed to this state. Constant fatigue, lack of concentration and mood swings become part of their daily life, preventing them to show their full potential, even without realizing it. But what is it about sleep that is so important?
Sleep can be divided into four stages. The first three stages are defined as NREM-sleep (non-rapid eye movement sleep). Stage 1 and 2 are light sleep and stage 3 is deep sleep. The fourth stage is called REM-sleep (rapid eye movement sleep) and is the sleep stage that is usually associated with dreams.
When we sleep, we cycle through each of those stages several times, every sleep cycle being around 90 minutes long. As it draws near morning, the REM-sleep stages become significantly longer, while the NREM-sleep is more prominent early in the night.
Both the NREM-sleep and REM-sleep play a crucial role when it comes to memory consolidation and our ability to learn and absorb new things.
Stages 1 & 2 (NREM)
The first two stages are defined as light sleep. Here, our heartbeat and respiration slow down, our muscles relax with occasional twitching. Body temperature drops, and our eyes stop moving. Brain wave activity starts to slow down but shows brief bursts of electrical activity. Here you are easily awakened. We spend the most time in light sleep.
Stages 3 (NREM)
Stages 3 are defined as deep sleep. Deep sleep is essential for us to feel invigorated once we wake up the next morning. Our heartbeat and respiration drop to their lowest level and our muscles relax even more than in light sleep. Brain wave activity slows, showing long, steady waves, and our blood pressure drops. In this stage, the lymphatic system of the brain becomes active, removing waste from your brain and making sure everything is intact for the following day. Muscle growth and repair also takes place in deep sleep. You will have difficulty waking up during this stage.
REM-sleep
As the name indicates, REM-sleep is characterized by rapid eye movements. However, the rest of our muscles are in a temporary state of paralysis. This prevents you from acting out your dreams while sleeping and gives your muscles time to rest. During REM-sleep, our heartbeat and blood pressure levels increase, and breathing becomes faster. Our brain activity increases drastically, resembling the activity we see in wakefulness. Our sleep pattern alters through our life, for example, newborns spend way more time in REM-sleep, but that time decreases as we get older.
Near all our dreaming takes place in REM-sleep. We spend about 2 hours every night dreaming, even though we might not remember it when we wake up. It is still not clear why we dream, nevertheless, REM-sleep has been associated with memory- and emotional processing, as well as promoting our creativity and problem-solving ability. Some scientists believe dreams to be essential when dealing with bad or even traumatizing memories, as well as serving as a link between old memories and recent events, showing us things from a new perspective. However, these explanations are only theories, still to this day, dreams remain a mystery.
Contrary to what many people believe, our brain is highly active during sleep. Several structures within the brain play a
significant role when it comes to sleep.
The suprachiasmatic nucleus (SCN) is located within the hypothalamus in our brain. It consists of thousands of cells, forming a cluster that can receive and process information about light exposure directly from our eyes. Using that information, the SCN can control our circadian rhythm, adjusting it to light exposure. The SCN than forwards the information to a part of the brain called the pineal gland. The pineal gland receives the signals and, if needed, produces melatonin, a hormone that we produce once it starts to get dark, informing our body it is approaching bedtime.
The hypothalamus then communicates with the brain stem, located at the base of the brain. The brain stem controls the transitions between wake and sleep by producing a chemical called GABA (gamma-aminobutyric acid). GABA is an inhibitory neurotransmitter that acts to reduce the activity of the arousal centers in the brain, allowing us to fall asleep. The brain stem also sends signals to relax your muscles during REM-sleep, to make sure we do not act out our dreams.
The basal forebrain also controls sleep and wakefulness, by using the compound adenosine. For every moment that we stay awake, adenosine keeps piling up in our brain, binding to certain receptors that gradually increase our need for sleep. Eventually, this need becomes so strong that sleep
becomes inevitable, whether we like it or not. However, the receptors in our brain can be tricked, a solution that many people take advantage of every day. Caffeine binds to the same receptors as adenosine, blocking its
actions and allowing us to stay awake even though the amount of adenosine has come to a critical point.
The thalamus acts as a messenger between the senses and the cerebral cortex, the part of the brain that interprets and processes information regarding our memory. The thalamus is dormant during most of our sleep, but during the REM-stage it becomes active and starts sending information to the cerebral cortex that makes its way into our dreams. The amygdala, which is involved in processing emotions, is also highly active during REM-sleep. Thus, we assume REM-sleep to play a crucial role when it comes to our memory and emotions.
References and further information can be found here:
https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep
https://www.landlaeknir.is/um-embaettid/greinar/grein/item14684/Sefur-thu-nog-
https://www.heilsuvera.is/efnisflokkar/svefn-og-hvild/mikilvaegi-svefns/
https://www.sleepfoundation.org/articles/how-much-sleep-do-we-really-need
Neuroscience of sleep
In this TED talk, circadian neuroscientist Russell Foster discusses the importance of sleep for our brain. He shares three popular theories about why we sleep, the effect of sleep deprivation on the society, and the relationship between sleep and mental health.
Sleep is your superpower
In this TED talk, sleep expert Matthew Walker discusses the science on sleep‘s impact on learning, memory and immune system in addition to giving advice on how to improve your sleep.
Obstructive sleep apnea is a serious sleep disorder, causing you to stop breathing, repeatedly, during sleep. The disorder is usually followed by excessive sleepiness.
A breathing pause, or “apnea”, occurs when the muscles in the back of the throat fail to keep the airway open. When we sleep, the muscles of the upper airway relax. If you sleep on your back, the tongue might fall back, blocking the airway and limiting the airflow. Your brain and body may become oxygen deprived, resulting in numerous attempts for you to try and catch your breath. You may wake up, only to fall back asleep and have the same pattern repeated. In the worst cases, this happens a few hundred times a night, impairing the sleep quality drastically.
The breathing pauses must last at least ten seconds and occur at least five times an hour, to be diagnosed as sleep apnea. 5-15 breathing pauses an hour indicate mild sleep apnea, 15-30 pauses an hour is defined as moderate sleep apnea, and more than 30 pauses an hour indicate severe sleep apnea.
Individuals, who suffer from sleep apnea, often wakeup several times a night, even though they have no memory of it the next morning. This can cause overwhelming sleepiness during the day. You may have difficulty concentrating or even fall asleep unintentionally. This can be highly dangerous, especially when it comes to drowsy driving. Daytime sleepiness can be measured using a so-called Epworth Sleepiness Scale (ESS).
Sleep apnea can negatively affect your body and has been associated with numerous health problems. This includes high blood pressure, heart disease, stroke, depression, diabetes, mood swings, and memory problems. Sleep apnea is also proven to have a negative effect on work and school performance.
Being overweight is a major risk factor when it comes to sleep apnea. According to studies, 60-70% of those who suffer from sleep apnea have excess body weight. Other common risk factors are age (middle-aged people are at higher risk), gender (males are more prone to suffer from the disorder), and family history.
Several ways have proved to be successful when treating the disorder. It is recommended to keep a consistent sleep schedule and be sure to get 7-8 hours of sleep every night. Substances such as alcohol and caffeine should be avoided late in the evening, as they can increase the symptoms. Overweight individuals are advised to lose weight, as that can decrease the symptoms drastically. In severe cases, continuous positive airway pressure machine (CPAP) may be needed.
If you believe you suffer from sleep apnea you should consult a doctor.
References and further information can be found on the American Academy of Sleep Medicine’s website and the website of the National Sleep Foundation:
http://sleepeducation.org/essentials-in-sleep/sleep-apnea https://www.sleepfoundation.org/sleep-apnea