There are more than 100 different sleeping and waking disorders, and it is easy to confuse them. Sleep deprivation often occurs with sleeping disorders.
If you cannot sleep for more than four to five hours per night (or less), you may have sleep deprivation. In addition, regular sleep interruptions from things like night terrors or "sleep starts" can also lead to sleep deprivation.
If you have trouble falling asleep or staying asleep, your sleep deprivation may be caused by insomnia. But it can also be caused by other sleep disorders.
Not everyone who sleeps less than the recommended seven to nine hours per night has a sleep disorder.
For example, if you need fewer than six hours of sleep every night and don't have sleep deprivation symptoms, you likely do not have insomnia. Instead, you may have a condition known as short sleep syndrome (SSS).
This article explains the difference between sleep deprivation and SSS.
Being unable to sleep can affect your health and well-being. Sleep disorders fall under the following categories:
- Insomnia: Difficulty falling asleep or staying asleep
- Hypersomnia: Excessive daytime sleepiness caused by narcolepsy, obstructive sleep apnea, and other medical conditions
- Circadian rhythm disorders: When your biological clock is out of sync, such as in jet lag, irregular sleep-wake syndrome, and shift work syndrome
- Parasomnias: Behaviors that interrupt your sleep, such as sleep terrors, sleepwalking, and REM sleep behavior disorder
All of these conditions can cause sleep deprivation. Often, they affect your ability to function normally as you go through your day. Symptoms of sleep deprivation include:
- Difficulty learning
- Increased carbohydrate cravings
- Less interest in sex
- Loss of motivation
- Trouble concentrating
- Weight gain
Risks of Sleep Deprivation
Over time, chronic sleep deprivation can weaken your immune response, leading to infections.
It may also impact insulin production, increasing your risk for type 2 diabetes.
In addition, sleep deprivation can elevate your blood pressure, upping your risk of heart disease.
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This video has been medically reviewed by Sanja Jelic, MD
Short Sleep Syndrome
Unlike sleep deprivation, people with short sleep syndrome (SSS) regularly need fewer than six hours of sleep per night and can still function normally.
People with SSS perform well at work or school even though they have short periods of sleep. They don’t feel the need to take naps or catch up on sleep on weekends.
The cause of short sleep syndrome is not well understood. However, a 2014 study published in the journalSleep strongly suggests that genetics play a key role.
Affects health and well-being
Is often caused by a sleep disorder
Sleep is inadequate
Short Sleep Syndrome
Does not cause negative symptoms
May be caused by a gene mutation
Sleep is adequate(Video) Why 4 Hours Of Sleep Is Terrible For You — Even If You Don't Feel Tired
SSS and Gene Mutations
In one study, two non-identical twins got almost identical amounts of rapid eye movement (REM) and non-rapid eye movement (NREM) sleep. One twin had a mutation of the BHLHE41 gene and needed a few hours of sleep per night. The other didn't have the mutation and required a full night's rest to function normally.
It is thought that gene changes like this interfere with a person's sleep patterns and their drive for sleep. Usually, these kinds of sleep interferences would cause symptoms of sleep deprivation. But in people with certain gene mutations, it doesn't.
For some reason, specific changes to certain genes alter the way the brain responds to a lack of sleep. As a result, the internal clock that controls sleep is shortened without harming a person's physical or mental health.
SSS is when a person requires fewer hours of sleep, but they don't experience symptoms of sleep deprivation. Researchers have found that mutations in certain genes may be responsible for SSS.
Sleep deprivation can be caused by many different sleep disorders, including insomnia. It can cause symptoms that affect your ability to function throughout the day. For example, if you have sleep deprivation, you may have trouble concentrating, feel tired all of the time, or be crabby.
People with SSS, on the other hand, need less sleep. They do not experience negative symptoms as a result. In addition, research has found certain gene mutations in people with SSS.
A Word From Verywell
If you are not adversely affected by short sleep duration, you don't have insomnia and shouldn't be worried. Waking up refreshed after a few hours of sleep is a sign of good health, not an illness.
However, call your healthcare provider if a sleep problem lasts for more than three weeks and affects your ability to work, take care of your children, or manage daily routines. They may refer you to a sleep specialist.
Don't try to self-diagnose and self-treat what you assume to be insomnia. In some cases, poor sleep patterns may be a sign of a serious medical condition requiring specific treatment and care.
Frequently Asked Questions
Is it bad to only get six hours of sleep?
Not always, though it's less than the general recommendation of seven to nine hours per night. Some people can get by just fine with six hours of sleep each night, while others may need up to eight or nine hours. Sleep needs can be influenced by certain factors like genetics, age, overall health, and amount of daily activity.
Why can't I stay asleep through the night?
There are many reasons why people have trouble staying asleep at night. Common reasons include the following:
(Video) Insomnia: why can't I sleep?
- Poor sleep environment caused by loud noises or light
- Too much caffeine
- Back pain
- Shifting hormones
- Drinking alcohol before sleep
- Eating before sleeping
What is short sleep syndrome?
Short sleep syndrome describes people who can function normally with less than six hours of sleep each night. It is believed to be genetic.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Medic G, Wille M, Hemels ME. Short- and long-term health consequences of sleep disruption. Nat Sci Sleep. 2017;9:151-161. doi:10.2147/NSS.S134864
Pellegrino R, Kavakli I, Goel N et al. A novel BHLHE41 variant is associated with short sleep and resistance to sleep deprivation in humans. Sleep. 2014;37(8):1327-1336. doi:10.5665/sleep.3924
American Sleep Association (ASA). 7 reasons why you can't stay asleep.(Video) Pulling an All-Nighter vs. 2 Hours of Sleep: Which is Worse? – Healthy Living and Diet Tips–SELF
University of California, San Francisco (UCSF). After 10-year search, scientists find second 'short-sleep' gene.
By Brandon Peters, MD
Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist.
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Why can't I sleep for more than a few hours at a time? ›
Stress. Poor sleep environment caused by loud noises or light. Too much caffeine. Back pain.Why can't I sleep for long enough? ›
Anxiety, stress, and depression are some of the most common causes of chronic insomnia. Having difficulty sleeping can also make anxiety, stress, and depression symptoms worse. Other common emotional and psychological causes include anger, worry, grief, bipolar disorder, and trauma.Why do I wake up after 3 hours sleep? ›
Reasons this might happen include drinking caffeine or alcohol late in the day, a poor sleep environment, a sleep disorder, or another health condition. When you can't get back to sleep quickly, you won't get enough quality sleep to keep you refreshed and healthy.Why do I only need 4 hours of sleep? ›
Some People Have a Superhuman Strength: Only Needing 4 Hours of Sleep. These “short sleepers” don't necessarily do it by choice—they're genetically programmed to require less shut-eye. Short sleepers are people who do well with about half of the shut-eye that the rest of us require to function.Why do I wake up every 2 hours at night to pee? ›
Nocturia is a condition in which you wake up during the night because you have to urinate. Causes can include high fluid intake, sleep disorders and bladder obstruction. Treatment of nocturia includes certain activities, such as restricting fluids and medications that reduce symptoms of overactive bladder.Why can't I go back to sleep after waking up? ›
The inability to fall back asleep after waking up is medically known as sleep-maintenance insomnia. Studies have found that anywhere from 10 to 60 percent of people experience insomnia. Other forms of insomnia can cause: difficulty falling asleep.How can I stop waking up multiple times at night? ›
Tips to help you stay asleep
Avoid heavy meals, alcohol and stimulants (coffee or smoking) close to bedtime. Exercise daily, but not too close to bedtime.
- Transient insomnia - Less than one month.
- Short-term insomnia – Between one and six months.
- Chronic insomnia – More than six months.
Insomnia in children can begin at any time, from infancy through adolescence, and in some cases can develop into a long-term problem. Symptoms can include: bedtime refusal and struggles going to bed.What is the 321 sleep Rule? ›
Don't eat or drink alcohol 3 hours before bed. Stop working 2 hours before bed. Get away from your screens 2 hours before bed. Hit the snooze button zero times.
Does melatonin help you stay asleep? ›
Your body likely produces enough melatonin for its general needs. However, evidence suggests that melatonin supplements promote sleep and are safe for short-term use. Melatonin can be used to treat delayed sleep phase and circadian rhythm sleep disorders in the blind and provide some insomnia relief.Why do I keep waking up at 4am and can't go back to sleep? ›
Anxiety or depression
Stress can make it hard to get to sleep in the first place (that's called sleep-onset insomnia). But anxiety can also cause you to wake up in the middle of the night and have trouble getting back to sleep (called middle insomnia, or sleep-maintenance insomnia).
The pattern of short sleep usually begins in childhood or adolescence and continues into adulthood. Researchers believe it may develop due to a gene mutation. This mutation may be what enables people to function well on fewer than six hours of sleep each night.Is there a gene that lets you sleep less? ›
They found a rare mutation in the ADRB1 gene that was being passed through the family. Family members who inherited one copy of this mutant gene had a shortened sleep cycle. The ADRB1 gene codes for the β1-adrenergic receptor.How many hours does Elon Musk sleep? ›
Elon Musk says he is "fairly nocturnal" and only sleeps about six hours a day. The world's richest man made the comments during an August 5 episode of The Full Send podcast. He said he usually goes to sleep at about 3 a.m. and wakes up after about six hours at 9 a.m. or 9:30 a.m.Can you train yourself to not pee at night? ›
Limit your intake of fluids two hours before bedtime
You'll also want to limit alcohol and caffeine, which are bladder stimulants, throughout the day. If you're struggling with nighttime urination, cut back to just one alcoholic beverage, or none at all, and decrease your current caffeine intake.
Best times to check. You don't have to look in the toilet bowl every time you urinate to keep tabs on your health. Clayman recommends you check twice a day — first thing in the morning and right before bed. Morning is when your urine will be most concentrated.How many times should you wake up to pee at night? ›
Nighttime urination is likely excessive if you get up to use the bathroom twice a night or more. During sleep time, your body produces less urine that is more concentrated. This means that most people don't need to wake up during the night to urinate and can sleep uninterrupted for 6 to 8 hours.Why do I wake up at 3am every night and can't go back to sleep? ›
If you wake up at 3 a.m. or another time and can't fall right back asleep, it may be for several reasons. These include lighter sleep cycles, stress, or underlying health conditions. Your 3 a.m. awakenings may occur infrequently and be nothing serious, but regular nights like this could be a sign of insomnia.How do I fall asleep again after waking up? ›
- Use deep breathing to fall back asleep. ...
- Try guided sleep meditations and muscle relaxation. ...
- Stop the blame game. ...
- Avoid clock watching. ...
- Don't drink alcohol before bed. ...
- Write down your worries. ...
- Beware of blue light and stimulation. ...
- Get up after 20 minutes.
What are the bad side effects of melatonin? ›
Other, less common melatonin side effects might include:
- Vivid dreams or nightmares.
- Short-term feelings of depression.
- Stomach cramps.
- Decreased appetite.
- Urinary incontinence at night.
Middle insomnia describes a difficulty maintaining sleep after initial sleep onset. For these individuals, sleep is fragmented with frequent awakenings at night. Middle insomnia is commonly associated with neurological syndromes (e.g., RLS), pain syndromes, or depression.Why do I wake up tired after 8 hours of sleep? ›
Most likely, you're still tired after eight hours of sleep because of these three factors: (1) you don't know your sleep need, (2) you're not taking into account your sleep efficiency, and (3) you carry sleep debt.What is the number one cause of insomnia? ›
It's not always clear what triggers insomnia, but it's often associated with: stress and anxiety. a poor sleeping environment – such as an uncomfortable bed, or a bedroom that's too light, noisy, hot or cold. lifestyle factors – such as jet lag, shift work, or drinking alcohol or caffeine before going to bed.What is the cure for insomnia? ›
Treating insomnia typically involves sleep-inducing medication, cognitive behavioral therapy for insomnia (CBT-i), or a combination of both of these measures. Positive lifestyle changes may alleviate symptoms for some people, as well.What diseases cause insomnia? ›
Examples of conditions linked with insomnia include chronic pain, cancer, diabetes, heart disease, asthma, gastroesophageal reflux disease (GERD), overactive thyroid, Parkinson's disease and Alzheimer's disease.How many hours do insomniacs sleep? ›
Recommended hours of sleep per day per age.
|Age group||Recommended hours of sleep per day|
|Teen (13–18 years)||8–10 hours|
|Adult (18–60 years)||7 or more hours per night|
The hours a child spends sleeping gradually diminishes to about 11 hours by the time they reach the age of four, and continues to decline until the adolescent years, when a teenager requires only nine hours of sleep. Children and teens generally spend more time in a deep sleep than adults.Can insomnia go away? ›
“Acute insomnia, whether you are given a medication for it—that is, a sedative to help you sleep—or not, does go away in weeks to months, usually less than three months,” said Dr. Rosen, even if you do nothing.”What is the best sleep schedule for humans? ›
In general, though, people should aim to fall asleep a few hours after dark and wake up within the first hours of sunlight in the morning, where possible. General guidelines indicate that the average adult needs about 7–9 hours of sleep each night.
What is the best time limit for sleeping? ›
You can figure out the best bedtime for your schedule based on when you have to wake up in the morning and counting backward by 7 hours (the recommended minimum per night for adults). For example, if you need to be up by 6 a.m., you should consider winding down before 11 p.m.Can you split your sleep into 2? ›
Biphasic sleep is a sleep pattern in which a person splits their sleep into two main segments per day. They may sleep longer at night, and then take a nap during the day. Or, they may split their nighttime sleep up into two segments. Biphasic sleep is also referred to as segmented or bimodal sleep.Why not take melatonin every night? ›
You Might Increase Your Risk for Some Health Issues
Even though melatonin is a hormone, not a supplement, it still has side effects and medical interactions, notes Dr. Weiss. "For example, some people might experience side effects after taking melatonin, including drowsiness, stomach aches or dizziness," says Dr.
Do not use melatonin if you are pregnant or breastfeeding or have an autoimmune disorder, a seizure disorder or depression. Talk to your health care provider if you have diabetes or high blood pressure.What is alternative to melatonin? ›
Other supplements including magnesium, valerian root, tart cherry, L-theanine, lavender essential oil, and GABA are worth considering as alternatives to melatonin.Does magnesium before bed help you sleep? ›
One study of older adults with insomnia found that magnesium supplementation at a dose of 500 milligrams daily for eight weeks helped them fall asleep faster, stay asleep longer, reduced nighttime awakenings, and increased their levels of naturally circulating melatonin.How do I stop waking up at 3am? ›
People whose sleep is disrupted by waking up at 3 a.m. can try following healthy sleep tips to sleep through the night more consistently. Avoid caffeine and alcohol: Both caffeine and alcohol are associated with disrupted sleep, especially when they are consumed later in the day.Why can't I sleep at night even when I'm tired? ›
Insomnia, the inability to get to sleep or sleep well at night, can be caused by stress, jet lag, a health condition, the medications you take, or even the amount of coffee you drink. Insomnia can also be caused by other sleep disorders or mood disorders such as anxiety and depression.Why can't I sleep longer than 2 hours? ›
Stress. Poor sleep environment caused by loud noises or light. Too much caffeine. Back pain.What is it called when you sleep too little? ›
Sleep deprivation is when a person doesn't get enough sleep. This can be a short-term issue, affecting one or a few nights, or it can be a chronic concern that lasts weeks or even months. Sleep deprivation can happen for countless reasons, many of them harmless, but it's also a key symptom of certain health conditions.
Why am I wide awake after 4 hours of sleep? ›
Finding yourself wide awake after a few hours of sleep, or waking often during the night is called "parasomnia" or "sleep maintenance insomnia," and it's much more common than people think.Do high achievers sleep less? ›
Generally, high achievers tend to sleep less, Brager tells CNET. "If you look at US presidents, successful CEOs and military leaders, many report sleeping little but feeling fine and don't need stimulants to stay awake," she says. "Daily sleep needs fall along the bell curve like most physiological processes in nature.Does less sleep affect your brain? ›
Sleep deprivation makes us moody and irritable, and impairs brain functions such as memory and decision-making. It also negatively impacts the rest of the body – it impairs the functioning of the immune system, for example, making us more susceptible to infection.What is the super sleeper gene? ›
A mutation in the gene DEC2 allows for some people to be natural short sleepers. It's every over-achiever's dream: a gene mutation that allows them to function normally with just four to six hours of sleep a night instead of the normal eight.How many hours did Bill Gates sleep? ›
On the other hand, we have some people, like Oprah Winfrey (8 hours), Serena Williams (7 hours), and Bill Gates (7 hours) who definitely stick to the expert's advice of getting between 7–9 hours' sleep.How many hours did Bill Gates sleep a day? ›
Now, the billionaire Microsoft co-founder gets at least seven hours of shut-eye, and wrote that all people need that much, “even if you've convinced yourself otherwise.”
10 HOURS OF SLEEP AND ONE-SECOND NAPS
It's common knowledge that sleep is good for your brain – and Einstein took this advice more seriously than most. He reportedly slept for at least 10 hours per day – nearly one and a half times as much as the average American today (6.8 hours).
Go to sleep at the same time each night, and get up at the same time each morning, even on the weekends. Don't take naps after 3 p.m, and don't nap longer than 20 minutes. Stay away from caffeine and alcohol late in the day. Avoid nicotine completely.How come I can't sleep even tho I had little hours of sleep? ›
Wondering why you can't sleep even though you're tired? It's probably due to poor sleep hygiene, circadian misalignment, and/or medical conditions like insomnia.Why can't I sleep even though I've been up for 24 hours? ›
If you're tired but can't sleep, it may be a sign that your circadian rhythm is off. However, being tired all day and awake at night can also be caused by poor napping habits, anxiety, depression, caffeine consumption, blue light from devices, sleep disorders, and even diet.
Can not sleep more than 6 hours? ›
Short sleeper syndrome (SSS) is a sleep condition characterized by sleeping for fewer than six hours each night. Most adults need seven or more hours of sleep each night to feel rested in the morning. Those with SSS, however, can function normally throughout the day despite less sleep.Why do I wake up at 3am and can't go back to sleep? ›
If you wake up at 3 a.m. or another time and can't fall right back asleep, it may be for several reasons. These include lighter sleep cycles, stress, or underlying health conditions. Your 3 a.m. awakenings may occur infrequently and be nothing serious, but regular nights like this could be a sign of insomnia.Can go to sleep but can't stay asleep? ›
Being unable to stay asleep is a type of insomnia, too. It's referred to as maintenance insomnia, sleep maintenance insomnia, and, sometimes, middle-of-the-night insomnia. Most people experience some type of insomnia on occasion, usually because of stress.What health conditions cause insomnia? ›
Examples of conditions linked with insomnia include chronic pain, cancer, diabetes, heart disease, asthma, gastroesophageal reflux disease (GERD), overactive thyroid, Parkinson's disease and Alzheimer's disease. Sleep-related disorders.What are 5 effects of lack of sleep? ›
An ongoing lack of sleep has been closely associated with hypertension, heart attacks and strokes, obesity, diabetes, depression and anxiety, decreased brain function, memory loss, weakened immune system, lower fertility rates and psychiatric disorders.How can I cure insomnia? ›
- Stick to a sleep schedule. Keep your bedtime and wake time consistent from day to day, including on weekends.
- Stay active. ...
- Check your medications. ...
- Avoid or limit naps. ...
- Avoid or limit caffeine and alcohol and don't use nicotine. ...
- Don't put up with pain. ...
- Avoid large meals and beverages before bed.
It depends on the cause of the sleep deprivation. If it is due to unrelenting insomnia, seek care at the doctor's office or Urgent Care. If you are seizing or hallucinating, get to the ER.What does broken sleep do to your body? ›
In otherwise healthy adults, short-term consequences of sleep disruption include increased stress responsivity, somatic pain, reduced quality of life, emotional distress and mood disorders, and cognitive, memory, and performance deficits.