Let’s be honest, we spend most of our day either sleeping or dreaming about our next nap. But, we know very little about this basic human necessity – sleep. Scientists have only started looking into this topic over the last 25 years and have discovered things we never even dreamed about (pun intended). Here are some eye-opening facts about sleep that may come in handy the next time you have to justify why taking a mid-day nap is crucial.
Humans Can’t Sneeze While Sleeping
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We are more prone to sneezing while asleep due to the mucus membrane swelling up when we lie down. However, because we aren’t moving enough to stir up dust, there isn’t anything irritating our nose. Also, during the stage of our sleep cycle where dreaming occurs, certain parts of our brain shut off. So, the signal the brain usually sends to our nose to sneeze is, well, sleeping.
People Who Were Born Blind Dream in Touch, Smells, and Sounds
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Blind people do dream, although their dreams are different from those of sighted people. Dreams are made up of experiences one has had while they were awake. For those that can see, their dreams will include visual memories, such as seeing the beach or waves. However, the dreams of people that can’t see include more sounds, smells, and how things felt to the touch. In other words, they will dream about the smell of the ocean, the way the sand felt between their toes, and the sound of the waves.
The Feeling Of Falling Down as You’re Falling Asleep is Called Hypnic Jerks
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Have you ever experienced the sensation of falling just as you’re about to fall asleep? Well, it is not only normal but has a name – hypnic jerks. Hypnic jerks, or ‘sleep starts’, are involuntary muscle contractions that usually occur just as the person is transitioning from an awake state to a sleeping state. While there is still no clear cause for these sudden jolts, scientists believe it might relate to exercising late at night, or stress and anxiety.
The Record For Longest Period Without Sleep is 11 Days
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In 1964, Randy Gardner, who was just 17 at the time, set the record for the longest period a human has gone without sleep. Gardner stayed awake for 264.4 hours, which is about 11 days. According to reports, the lack of sleep caused the record-breaker to experience moodiness, problems with concentration and short-term memory, as well as, hallucinations. After breaking the record, Gardner slept for 14 hours straight.
Dolphins Shut Off Only One Half of Their Brain While Asleep
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Unlike humans, dolphins have to consciously think to breathe. Therefore, dolphins only shut off half their brain when they fall asleep. This is called unihemispheric – one hemisphere of the brain goes to sleep while the other remains awake. So, half their brain is asleep while the other half keeps them coming up for oxygen. Surprisingly, dolphins spend about 1/3 of their lives fast asleep.
Lack of Sleep Will Kill You Faster Than Lack of Food
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According to reports, humans can function longer without food than they can without sleep. After several days of no food, a person will feel weak and will most look thinner. But, after just a few days of not sleeping, the person will be unable to function. Interestingly, sleep deprivation has been used as a form of torture in the past.
Falling Asleep In Less Than Five Minutes Indicates You’re Sleep-Deprived, as Ideally, You Should Fall Asleep in 10-15 Minutes.
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According to ABC News, the FDA states that falling asleep in less than five minutes may indicate one is suffering from a sleep disorder and is sleep-deprived. It is normal to take anywhere between 10 to 20 minutes to fall asleep at night. If falling asleep takes longer than 20 to 30 minutes, that could indicate a different sleeping disorder – insomnia.
Childhood Exposure to TV in Black and White Made People’s Dreams in Black and White
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Before TV was in color, it was in black and white. And, as it turns out, it affected people’s dreams. According to the New York Times, a study published in 2008 found that people over 55 who were exposed to black and white television as children and had little excess to color TV reported dreaming in black and white about a quarter of the time. Going further back, studies from the 1940s showed that three-quarters of Americans reported they “rarely” or “never” see any color in their dreams.
Humans Are the Only Mammals That Can Delay Sleep
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Humans are the only mammals known to willingly delay sleep. We, humans, are able to keep ourselves awake even when our body is showing signs of tiredness and needs to go to sleep. Unlike us, all other mammals are unable to willingly delay their sleep and must succumb to their need to sleep.
Apparently, Losing an Hour of Sleep Due to Daylight-Saving Time Can Be Deadly, With Hospitals Reporting a 24% Spike in Heart-Attack Visits on the Morning After the Switch.
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Apparently, losing even an hour of sleep at night could have a deadly effect. According to Insider, on the Monday after the annual ritual of Daylight-saving in which we push the clocks forward one hour, hospitals report a 24% spike in heart attack visits around the US. On the other hand, on the day after we turn back the clocks and people enjoy an extra hour of sleep, heart attack visits drop 21%.
Elephants Sleep Less Than Any Other Animal With an Average of Two Hours a Night
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A study conducted by researchers from the University of the Witwatersrand in South Africa found that wild elephants are the mammals with the shortest sleep time known. The research found that elephants sleep two hours per day on average, if at all, and do so mostly standing up. The elephants sometimes went up to 46 hours without sleep while walking distances of about 19 miles (30km), probably to avoid threats like lions and poachers.
Sleep Is Different For Women and Men, with Women Getting, on Average, More Sleep
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According to the National Sleep Foundation, when it comes to sleep, there are differences between women and men. Women and men’s circadian rhythms, which is the body’s 24-hour internal clock, are slightly different. On average, men have a longer circadian rhythm by six minutes, meaning they feel less tired in the evening. Women, on the other hand, are more likely to have a shorter internal clock, meaning they tend to both go to bed and wake up earlier.
Google Was Invented in a Dream
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Believe it or not, Larry Page dreamt up the idea of Google! In 1966, college-student Larry Page feared that a clerical mistake led to his acceptance to the university. Due to this irrational fear, Page dreamt one night of downloading and storing the internet on individual computers. Soon after waking up, Page did some simple calculations and concluded that while it wasn’t possible, he was able to create a searchable database of links to web pages.
Every Face You See in Your Dreams Belongs to Someone You’ve Met Before
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Have you ever dreamt about someone you couldn’t recognize and believed it’s a face created in your dreams? Think again. The human brain cannot create new faces in dreams, hence that every person you see in your dreams is someone you’ve seen or met before. We encounter so many people every day, and we forget most of them quickly. These faces can, however, reappear in our dreams.
Sea Otters Sleep Holding Hands
This sleep fact is insanely adorable! While sleeping in water, sea otters hold hands to prevent drifting away and losing each other. One of the reasons behind this tradition is otters’ fear of losing their loved ones, and when baby otters are too young to hold their mother’s hand, their mothers will carry them around. Holding hands is also a way for otters to protect themselves from predators, as them drifting away from land together makes it harder for hunters to kill them.
You Forget 50% of Your Dreams Within Five Minutes of Waking Up and 90% Within Another Five Minutes.
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Very rarely do we remember a dream, let alone remember every detail of it. Not remembering many dreams isn’t for lack of dreaming, but rather due to the quickness in which we forget them. Within five minutes of a dream ending, we forget 50% of its content, and after additional five minutes, 90% of recollection is gone. According to Everyday Health, the best time to try to recall your dreams before forgetting them is within 90 seconds of waking up.
People Who Sleep Less, Eat More
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Studies found that people who slept less at night ate more throughout the day in comparison to well-rested individuals. According to Sleep Foundation, lack of sleep creates an imbalance in our body that decreases the levels of leptin, the hormone that tells our brain when we are full, and increases levels of ghrelin, the hormone that tells our brain we are hungry.
Twelve Percent of People Dream in Black and White
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While most people dream in color, studies found that about 12% of the population dreams in black and white. In a study from 2008, people under the age of 25 reported rarely dreaming in black and white, while people over the age of 55 reported dreaming in black and white about 25% of the time.
Sleep-Deprived People Have Reduced Pain Tolerance
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According to the National Library of Medicine, studies throughout time showed that reduction of time in bed leads to hyperalgesia – an increased sensitivity to pain. A study from 2009, for example, showed that sleepy individuals exhibited a more rapid finger withdrawal response, meaning reduced pain tolerance, to radiant heat than non-sleepy participants.
People Grow About 0.3 Inches (1 Centimeter) While Sleeping, Which They Then Lose Throughout the Day
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Did you know that you are taller in the morning than at night? Well, as it turns out, it’s due to the fact that people grow about 0.3 inches (1 centimeter) each night while they are sleeping, inches they will then lose throughout the day. According to NASA, when we lie down to sleep every night, gravity isn’t pushing down on our spine, leading to its stretching. As the day continues, however, the spine compresses back, and you’ll lose the height you “grew” overnight.
Snails Can Sleep for Three Years
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Snails are mostly active during the nighttime, as they need humidity to produce the mucus that allows them to slide from one place to another. However, when the weather is extremely hot or cold, snails can stay inside their shell for long periods of time. Although it’s rare, in extreme cases, where there are long periods of extreme weather, snails can sleep for three years, which is about one-third of their lives.
The Higher Your IQ, The More Interesting Your Dreams Are
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Some scientists claim that, on average, people who dream more often and more vividly have higher IQs. According to the claim, people with high intelligence experience very captivating dreams that last longer and are more dynamic than people with lower intelligence. However, most people do not remember most of their dreams and the average dream only lasts a few seconds.
Sleeping on the Job is Acceptable in Japan and is Seen as a Sign of Diligence
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In Japan, sleeping on the job is acceptable and considered a sign of diligence. The practice of napping in public, called inemuri (which means ‘present while sleeping’), is seen as a sign of dedication to the job, such that one stayed up late doing work or worked to a point of complete exhaustion, and may therefore be excused. People in Japan Japan have some of the longest working hours in the world and are also amongst the most sleep-deprived.
Studies Say Your Favorite Sleeping Position is Directly Linked to Your Personality
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Professor and sleep expert Chris Idzikowski surveyed over 1,000 British adults to discover if there is a link between their favorite sleeping position and their personality. Between professor Idzikowski’s findings were the following: fetal position can be linked to shyness and sensitivity. People who sleep on one side with arms outstretched may be open-natured yet somewhat suspicious and tend to stick to their decisions, while stomach sleeping with hands up or under the pillow could be linked to a sociable nature and a dislike of criticism.
Cats Spend Two-Thirds of Their Lives Asleep
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On average, cats spend about two-thirds of their lives asleep, sleeping between 13 to 16 hours per day. The reasoning behind cats’ sleeping habits originates from their evolutionary history. To conserve energy for hunting, chasing, etc., wild cats must sleep. Even if domesticated cats don’t need to hunt, they still have the instinct of sleeping and saving energy for it.
We Aren’t Featured in Our Own Dreams Until Age Three or Four
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Toddlers cannot dream about themselves, as we aren’t featured in our own dreams until we’re around three or four. According to psychologist David Foulkes, who studies children of various ages and their dreams, toddlers’ dreams look something like a slideshow and heavily feature animals and other familiar sights.
Before Alarm Clocks, There Were People Whose Job it Was To Wake You Up by Knocking on Your Window
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Ever wondered how people got up in time before the invention of alarm clocks? Well, in industrial Britain and until the 1970s, people would wake up to the sound of tapping on their windows. Back then, people and factories paid someone, then referred to as a knocker-upper, to knock on workers’ bedroom windows with a long stick to ensure they would arrive at work on time.
Blind People Who Weren’t Born Blind Can Still See in Their Dreams
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While people who were born blind can dream different senses like smell and sound, that isn’t necessarily the case for people who weren’t born blind. In fact, if a person wasn’t born blind or didn’t become blind as an infant, they can see in their dreams. However, the longer a person has been blind, the less likely they are to dream visually.
Deaf People Occasionally Use Sign Language in Their Sleep
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Not only do deaf people dream in sign language, but there are also many instances where people witnessed their deaf partners or children using sign language in their sleep. According to BBC‘s Science Focus Magazine, Science Focus, researchers in a 2017 case study witnessed a 71-year-old man with a severe hearing impairment sign in his sleep. They could also get an idea of what he was dreaming about by decoding his signs.
The Condition of Having Difficulty In Getting Out of Bed in the Morning is Called Dysania
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While everyone struggles with getting out of bed at times, failing to get out of bed for hours, and even days, due to an overwhelming need to stay in bed may indicate dysania. While it isn’t recognized as a medical condition, dysania is a long-term feeling that you’re unable to get out of bed, and even when you do, all you want is to go back to sleep, according to Healthline. Dysania could signal depression, chronic fatigue syndrome, and thyroid disorders, among other health issues.
The Anti-Diuretic Hormone (ADH) Is Released at Night to Suppress Our Need to Pee
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Ever wondered why you don’t need to pee at night as often as you do during the day? Well, here’s the answer. During the night, as we sleep, our body increases its production of a hormone called vasopressin, or antidiuretic hormone (ADH), which signals our kidneys to keep absorbing and recycling water, thereby preventing both dehydration and the creation of pee. Nevertheless, some water does pass through to the bladder, slowly filling it up, and many people still have to pee in the middle of the night.
It Isn’t Dangerous to Wake Up a Sleepwalker
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A popular myth claims that waking a sleepwalker is dangerous and will cause them harm. However, that is incorrect. It isn’t dangerous to wake up a sleepwalker, and they are in greater danger when walking around the house while still asleep. When facing a sleepwalker, try to ease them back to bed without using force, and if unsuccessful, try again later, all while assuring their safety.
Babies Need to Sleep 12-16 Hours Per Day
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Can barely squeeze in the recommended eight hours of sleep? Then good thing you don’t have the sleep requirements of a baby. According to guidelines from the American Academy of Sleep Medicine, babies should get between 12 and 16 total hours of sleep per day. The reasoning behind this is that sleep allows babies’ brains and bodies to develop.
Believing You Slept Well, Even If You Haven’t, is Believed to Improve Your Performance
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According to a 2014 study published in the Journal of Experimental Psychology, believing you got a good night’s sleep, even if you didn’t, improves your performance. The study found that telling participants they had a good night’s sleep – even if they hadn’t – performed better in tests that assessed their ability to listen and process information.
Sleep Isn’t a Static Process, But a Constant Cycle That Includes Five Stages
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While we say “sleep through the night,” sleep isn’t a static process. According to Sleep Foundation, there are five stages of sleep – the wake stage, one for rapid eye movement (REM) sleep, and three that form non-REM (NREM) sleep. After the initial stage of awakeness, NREM sleep is divided into three stages – N1 (falling asleep), N2 (light sleep), and N3 (slow-wave sleep) – which are followed by the REM stage. When you fall asleep at night, you cycle through these four stages in 90-minute or so intervals.
Disruptive Sleep-Related Disorders Are Called Parasomnias and Include Such Issues as Sleep Walking, Sleep Eating, and Sleep Sex
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Parasomnias are disorders that cause people to do things while sleeping, such as sleepwalking and sleep-talking. There are also rarer variations like sleep sex and eating. While it may sound amusing, these are serious issues. In a 2002 study, researchers from Stanford University found people who engaged in “sleep sex” – a range of nocturnal activities from disruptive moaning to committing violent sexual acts in their sleep. Sleep eating could also be dangerous when frequent, resulting in weight gain and even putting one at risk of developing type 2 diabetes.
Humans Spend One-Third of Their Lives Sleeping
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On average, a person spends about one-third of their life either sleeping or attempting to do so. The average person sleeps for eight hours every night and therefore, in a typical lifespan of 75 years, he/she sleeps for 25 years. While many people may look at this amount of time and think it’s a waste, it is necessary to enjoy the other two-thirds of our life!
Studies Suggest Women Need More Sleep Than Men
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Many have heard that women are better than men at multitasking, and, as it turns out, it doesn’t come without its consequences. According to a U.K. study, women need 20 more minutes of sleep than men, with the researcher attributing women’s multi-tasking and use of more parts of their brain as the reason for the additional time needed.
Sleep Improves Your Memory
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Sleeping helps boost your memory. According to Sleep Foundation, the three NREM stages of sleep prepare your brain to learn new information. During these stages, the brain also sorts through various memories from the previous day. Several studies have also shown that sleep-deprived individuals score lower on short-term memory tests compared to well-rested individuals.
The Fear of Sleep is Called Somniphobia
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Somniphobia causes extreme anxiety and fear over the thought of going to sleep. It’s not entirely certain what’s the exact cause of somniphobia, but it could be the result of other sleep disorders such as sleep paralysis and nightmare disorder.
Regular Exercise Helps You Sleep
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Working out is great for your body and your mind, and, as it turns out, it is also beneficial to your sleep. According to Charlene Gamaldo, M.D., medical director of Johns Hopkins Medical Center for Sleep, several studies show that exercise helps in falling asleep more quickly while also improving sleep quality.
Working Out Right Before Bedtime, However, May Damage Your Sleep
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While exercise benefits our sleep, its timing may matter. According to Johns Hopkins Medicine, exercising close to bedtime may damage people’s sleep. Several explanations could be to this occurrence. One, aerobic exercise causes the body to release endorphins that can keep you awake, and therefore should be done one or two hours before bed. Another reason may be that exercise elevates our core body temperature, which signals our body that it’s time to be awake.
Ducks Can Sleep With One Eye Open and One Side of Their Brains Awake
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Ducks can sleep with one eye open and one side of their brains awake! A 1999 study conducted by a sleep researcher at the Indiana State University found that in a row of mallards, the two birds located on both ends of the row kept one eye open. The researcher also discovered that while sleeping with one eye open, one part of the birds’ brain was alert, while the other was shut down. The phenomenon is a defense mechanism that allows ducks to be aware of their surroundings and protect themselves from danger.
Excessive Oversleeping is an Actual Condition Called Hypersomnia
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Oversleeping is an actual disorder! According to WebMD, Hypersomnia is a condition that entails trouble staying awake and refers to either excessive daytime sleepiness or excessive time spent sleeping. Hypersomnia may occur even after long stretches of sleep, with people who have it being able to sleep at any time and place. People with hypersomnia have difficulty functioning throughout the day as they lack concentration and energy due to tiredness.
Parents of Newborn Babies Lose Six Months Worth of Sleep in the First Two Years of Their Child’s Life
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According to the Independent, a survey found that new parents average four hours and 44 minutes of sleep each night during the first year of their baby’s life. In two years, adults should get about 3,650 hours of sleep, yet, parents of newborns receive only about 2,739 hours of sleep, creating a sleep deficiency of 912 hours, which adds up to about six months of insufficient sleep.
High Altitudes Damage Sleep Quality
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People who fly regularly, such as plane crews and business people, could be at a greater risk of sleep deprivation. The reason behind it is that flying at high altitudes leads to disturbance in our sleep due to the lack of oxygen. The lack of oxygen contributes to a condition called Cheyne Stokes, otherwise known as high-altitude periodic breathing (PB). Cheyne Stokes can affect anyone at high altitudes and can lead to several sleep disturbances and conditions, as well as a decrease in total time and quality of sleep.
Sleep Strengthens Your Immune System
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Sleep provides essential support to our immune system. A study by the University of California found that individuals who regularly got less than six hours of sleep a night were 4.2 times more likely to catch a cold than those who got at least seven hours of sleep. In addition, when we sleep, our body produces and releases the protein cytokines, which helps fight off viruses and infections.
Our Sense of Smell Decreases When Asleep
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Researchers found that smell sensitivity changes throughout the day, usually being the strongest at around 9:00 p.m. in the evening and weakest overnight. These findings may explain why smells generally don’t wake people from their sleep. One of the reasons fire alarms were invented was that, unlike smells, noises do wake us up.
A New Bed Can Increase the Amount of Sleep You Get at Night
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We all love and are excited about getting new things. And while often the excitement of something new can keep us up at night, that doesn’t seem to apply to a new bed. According to The Sleep Council, when we exchange our old bed for a new one, we can get up to 42 extra minutes of sleep!
Some of the Things You Can’t Do in Your Sleep Include Telling the Time or Reading a Book
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Certain things seem to have not been transferred from our world to the dreams realm. You may have never noticed it, but you cannot write or read during your dreams. That is because the areas of our brains that are responsible for interpreting language are much less active when we are asleep. Other things you cannot do in your dreams include telling the time, seeing yourself in a mirror, and tasting food.
Athletes Need Ten Hours of Sleep at Night
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While it is recommended that people get between seven to eight hours of sleep every night, that isn’t the case for pro-athletes. Athletes typically need more sleep than most, and it’s recommended that they get about ten hours of sleep every night. Due to their heavy physical needs, athletes may need this many hours of sleep to repair their muscles and recharge their energy.
Research Found That Fear Isn’t the Most Common Feeling Associated With Nightmares
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We usually associate nightmares with fear, and yet, studies found that their emotional impact is rarely due to fear. According to a study from the University of Montreal published in the journal Sleep, nightmares are more likely to reflect and impact us emotionally through feelings of sadness, confusion, and guilt rather than fear.
Sleeping on Your Side Has Health Benefits
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Apparently, sleeping positions could, potentially, have health benefits. Researches show that sleeping on the left side aids with digestion and waste elimination, as well as with reducing heartburn. In addition, according to Healthline, sleeping on your side may also help boost brain health and reduce snoring by keeping the tongue from falling into the throat and blocking your airway.
Throughout Your Life, It’s Likely You Took Naps Without Realizing It
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As you go through life, you’ve likely taken a nap of a few to several seconds without even realizing it. These naps are referred to as “microsleeps” and can occur everywhere. Microsleep can be the result of several conditions such as sleep apnea, narcolepsy, or sleep deprivation. People who experience microsleeps often remain unaware of them, believing that they were entirely awake or temporarily lost focus.
Sleepwalking Is More Prevalent Among Children Than Adults
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According to Sleep Foundation, sleepwalking occurs more often around children than adults. A 2015 study found that 29% of children between the ages of two to thirteen experienced sleepwalking. In adults, on the other hand, the prevalence is estimated to be up to 4%. According to CBS News, researchers found that about 8.4 million Americans sleepwalk each year.
Sleeping Well Helps You Lose Weight
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Think that exercise and a diet are all you need to lose weight? Think again. Getting the recommended amount of sleep at night is just as important as diet and exercise when attempting to lose weight. One of the reasons for it lies in the fact that a lack of sleep may lead to an increased appetite and a diminished feeling of fullness.
Dogs Turn Circles Before Lying Down as an Old, Wild Instinct of Making Their Own Bed
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Often, before lying down, dogs circle the place where they choose to settle in. Well, according to Live Science, this behavior dates back to their wild ancestors, who had to make their own beds. Back then, in a time before doggy beds and domestication, wild dogs had to pat down tall grass to make themselves comfortable beds.
In Order to Sleep, You Need to Cool Down
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According to WebMD, as bedtime approaches, our body temperature starts to fall, paving the way for a good night’s sleep. In a way to help us fall and stay asleep, our body tends to lose heat. That’s one of the reasons why an exercise too close to bedtime is not recommended (as it heats our body), as well as why it can be harder to fall asleep on hot nights.
Bears Don’t Poop During Hibernation
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During hibernation, which tends to last for six months, bears manage to not eat, drink, move, or, apparently, poop. How do they manage to do that, you ask? Well, according to the North American Bear Center, bears accumulate feces in the lower 7-15 inches of the intestine to form a ‘plug’ that prevents poop from coming out.
As Part of His Training, Swimmer Michael Phelps Slept in a Chamber that Simulated Sleeping at an Altitude of 9,000 Feet (2,743 meters)
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The most decorated Olympian of all time, Michael Phelps, revealed that, as part of his training, he slept in an altitude chamber designed to simulate oxygen levels at approximately 9,000 feet. In a 2012 interview, Phelps stated that he started using the chamber after noticing altitude helped him recover from workouts. Using the chamber helped Phelps, as well as other athletes, boost levels of oxygen-rich red blood cells.