I think sleep is pretty fascinating but that’s not surprising since it’s my speciality!
Curiosity about your nightly slumber shouldn’t be restricted to us, scientists. Below is a list of scientifically accurate and super interesting sleep facts for you to enjoy.
1. All animals that have a brain need to sleep.
This even includes some of the smallest creatures such as fruit flies.
Interestingly, the science is still out on whether animals without a brain, such as a jellyfish, require sleep.
2. You spend a third of your life asleep.
The average person sleeps for about 8 hours a night, which works out to one-third of the day.
Let’s say you live to be 80. By the time you die, you would have slept for approximately 26.6 years!
3. Your brain cleans itself while you sleep.
During the day you build up waste products in the brain that can keep it from functioning properly.
While you sleep, your brain switches on its own personal sewer system, called the glymphatic system, to flush the waste away.
4. People suffering from depression have more REM sleep.
Sleep is divided into two phases:
The first phase is Non-Rapid Eye Movement (NREM) sleep. During NREM, you have deep, restorative sleep.
The second phase is Rapid Eye Movement (REM) sleep. REM is when dreaming occurs.
Scientists discovered that people with clinical depression spend more time in the REM phase of sleep. Some researchers believe that dream sleep helps us process our emotions and this is why people with mood disorder require more REM.
5. It takes an average of 7 minutes to fall asleep.
It may seem like it takes longer but most people start stage 1 (light sleep) within 7 minutes of closing their eyes.
6. Yes, you die from a lack of sleep.
Just like breathing, drinking, and eating, if you stop sleeping, you’ll eventually die. Although it might take a while.
It’s hard to know exactly how long humans can survive without sleep because death from sleep deprivation is extraordinarily rare.
An extremely uncommon disease called fatal insomnia (FA) gives scientists some insight into how long a human can go without sleep.
FA destroys the areas of the brain that control sleep, resulting in chronic sleep loss. Death in individuals with FA occurs within a few months to a few years.
7. You can’t learn without sleep.
An important aspect of learning is taking the new information you’ve come across and turning it into a long term memory. Scientistic call this process memory consolidation.
Memory consolidation mainly occurs during stage 2 and 3 of NREM sleep.
This is why your learning and memory is so poor when you’re sleep-deprived.
8. Babies have the most REM sleep.
From the moment they’re born, babies spend half their sleep in the REM stage.
Scientists believe that REM sleep helps create pathways in the brain that allow babies and children to learn and develop language.
9. The length of time humans spend sleeping isn’t unique.
You’d think that being the most intelligent animals on the planet would mean we need the most sleep.
Interestingly, the amount of time we sleep compared to other animals is somewhere in the middle.
Scientists don’t know why we need 7-9 hours of sleep per night, while other animals, like koalas, need 22 hours, or giraffes, only need 2 hours a day.
To give you more perspective, the simple fruit fly has very similar sleep patterns to humans. They sleep around 8 hours at night and have a nap in the middle of the day.
Obviously, fruit flies are nowhere near as evolved as humans, so what gives?
Scientists think it’s not the length of sleep that makes humans special but how our sleep is organized. Unlike fruit flies and other animals, there are special biological processes that only occur during human sleep, regardless of total sleep time.
10. Sleep helps to strengthen your immune system.
When you’re sick with a viral infection, your body uses sleep to give your immune system a power-up.
Researchers found that sleep increases the activity of specialized immune cells that fight off viruses and it also makes the cells better at identifying infectious agents.
11. Women need more sleep than men.
Women need 20 more minutes of sleep on average than men.
Scientists don’t really understand what makes women sleep longer but some speculate it could be due to normal fluctuation in female hormones.
Another study found that poor sleep is associated with greater psychological distress and a higher risk for heart disease and type 2 diabetes in women. Women might compensate for this elevated risk by sleeping longer.
11. The most diagnosed sleep disorder is obstructive sleep apnea.
Not only is our society’s average weight and BMI getting larger but we’re also getting older due to an aging population. Both weight and age are major contributors to developing OSA.
12. You’re most likely to dream about falling.
Multiple surveys conducted by different sleep organizations from around the world consistently find that falling dreams are the most common.
In an American study, 53.5% surveyed reported having reoccurring dreams about falling followed closely by being chased at 50.9%.
This is not surprising since scientists believe that dream sleep helps us process our emotions and falling dreams are commonly associated with stress and anxiety.
13. Most teenagers have Delayed Sleep Phase Disorder.
DSPS delays the onset of the normal sleepiness we feel before bedtime by two or more hours. This means that most adolescents won’t feel ready to sleep until late into the night. It’s not uncommon for teens to stay up until 2-3 A.M.
DSPD conflicts with societal pressures, such as school start times, leaving teens feeling constantly sleep-deprived. Luckily, DSPD doesn’t last forever and most teens return to a normal sleep routine once they’ve finished puberty.
14. Your brain fluctuates in temperature while you sleep.
In order to initiate sleep and enter into the deep sleep stage, your brain has to undergo a minor drop in temperature. Conversely, before entering REM sleep, the brain increases in temperature.
This is why it’s easier to fall asleep in a cool environment.
15. Sleep loss has a similar effect to drinking alcohol.
Even moderate sleep loss causes mental impairments equivalent to being drunk.
Scientists found that after 17 to 19 hours without sleep, the mental performance of their test subjects was equivalent to or worse than individuals with a blood alcohol content (BAC) of 0.05%. This included a 50% reduction in their reaction time.
After longer periods without sleep, their performance reached levels equivalent to a BAC of 0.1%.
So please don’t drive while you’re sleep deprived!
16. Shift workers from all industries get the least amount of sleep.
This may not come as a surprise to those in a shift work industry.
A study by the Center for Disease Control (CDC) found that American night shift workers were consistently getting the least amount of sleep, with 44% getting fewer than six hours a day.
Maybe it’s time for a career change.
17. The amount of sleep you need changes as you age.
The amount of sleep you need is mostly dependent on what stage your brain is at of development.
Most major neurodevelopment happens during sleep so the younger you are, the more sleep you need! Newborns undergo the most neurodevelopment and need 16 to 20 hours asleep each day. Toddlers require 11 to 12 hours.
A gradual decline in the amount of sleep you need continues until adulthood. Once you reach adulthood, you’ll need 7-9 hours of sleep for the rest of your life.
While the elderly also need an average of 8 hours, brain decline means it becomes difficult to achieve the needed amount of sleep.
18. A rare gene mutation allows some people to survive on less sleep.
Very few people can live a healthy life while getting less than the recommended 7-9 hours of sleep.
A tiny percentage of individuals have a gene mutation that makes their sleep more efficient. When sleep is more efficient, you need less.
These lucky individuals get by on less than 6 hours of sleep per night with no detrimental effects on their health.
20. Elite athletes spend more time in deep sleep.
During deep sleep (stage 3), your body works hard to repair damage to your tissues and cells that occurred throughout the day.
Scientists discovered that competitive athletes spend more time in deep sleep compared to non-athletes. This is probably because they place more stress on their bodies and are more prone to injury, and thus require more tissue repair.
21. Alcohol makes your sleep worse.
Alcohol is classified as a depressant, which means it slows down your nervous system, making you feel drowsy.
Alcohol can make you fall asleep fast but it reduces the overall quality of your sleep.
Not only does alcohol have a diuretic effect that makes you need to urinate more often throughout the night, but it also affects your circadian rhythm, and inhibits your ability to transition into REM stage sleep.
Maybe you should pass on that nightcap!