The Effects of Sleep Deprivation on Your Body

What is Sleep Deprivation?

Sleep deprivation means not getting adequate sleep. It can mean you are not sleeping long enough or you are not getting enough quality sleep. Sleep deprivation can have both short- and long-term effects, including how you function in daily life, and chronic health problems, affecting both mental and physical health. Experts estimate 50 to 70 million Americans suffer from some type of sleep disorder.

Acute vs. Chronic Sleep Deprivation

Acute sleep deprivation is a short-term issue lasting one or more days. Chronic sleep deprivation is not getting enough sleep for weeks, months, or even years. 

Acute sleep deprivation can impact functioning the following day, including causing slowed thinking, a longer reaction time, poor concentration, and mood changes. Long-term sleep deprivation can have a negative impact on your mental and physical health, including an increased risk of serious health conditions such as cardiovascular disease. 

How Much Sleep is Enough?

How much sleep is enough varies by age. Remember, it’s not only the number of hours a person sleeps every night but also the quality of sleep they get. If a person sleeps enough hours but has poor quality sleep, they might still be sleep deprived.

According to the Centers for Disease Control and Prevention (CDC) and the Sleep Foundation, recommendations for the amount of sleep (daily hours) by age are as follows:

• Newborn babies (up to 3 months of age): 14 to 17 hours

• Infants (4 to 12 months of age): 12 to 16 hours, including naps

• Toddlers (1 to 5 years of age): 10 to 14 hours, including naps

• Young children (6 to 12 years of age): 9 to 12 hours

• Teenagers (13 to 18 years of age): 8 to 10 hours

• Adults (18 years and above): 7 to 9 hours

Sleep Insufficiency vs Sleep Deprivation vs Insomnia: What’s the Difference?

When people use the term “sleep deprivation” in casual conversation, they actually mean sleep insufficiency. And it’s common to confuse sleep deprivation and insomnia. Here are the definitions of these three terms:

• Sleep deprivation means going the whole night without sleep for one or more nights.

• Sleep insufficiency means sleeping for a shorter amount of time than what your body requires to stay healthy or having poor quality sleep because of sleep disruptions. You are physically able to sleep but unable to get enough sleep due to your schedule or disturbances.

• Insomnia means having difficulty falling asleep or staying asleep. You have ample opportunity to sleep but are unable to fall asleep or stay asleep even when you try.

Causes of Sleep Deprivation

Lifestyle Factors

• Unhealthy sleeping habits, such as inconsistent sleeping and waking up times.

• Use of electronic devices before bedtime.

• Consuming caffeine, other stimulants, or alcohol close to bedtime.

• Eating a heavy meal shortly before going to bed.

• Uncomfortable sleep environment, such as noise (partner snoring), light, or too hot/cold temperature in your bedroom.

• Shift work sleep disorder (working outside the usual daytime working hours), which can disrupt the body’s natural circadian rhythm (sleep-wake cycle).

• Sleeping in an unfamiliar place, such as a hotel room, can prevent you from getting enough sleep.

Interestingly, for a long time, it is believed that exercising in the late evening and before bedtime has been associated with difficulty getting a good night's sleep. However, recent studies suggest that moderate-intensity exercise in the evening does not affect sleep quality or the ease of falling asleep. 

Sleep Disorders 

• Primary insomnia.

• Parasomnias (disruptive sleep disorders such as sleepwalking, sleep paralysis, and night terrors).

• Bruxism (teeth grinding).

• Obstructive sleep apnea.

• Restless legs syndrome.

Other Physical Health Conditions

• Acute illnesses such as the common cold or flu.

• Chronic pain.

• Nocturia (getting up more than once at night to urinate).

• Diabetes.

• Neurological disorders such as Alzheimer’s disease and Parkinson’s disease.

• Concussion or traumatic brain injury.

• Substance abuse (excessive alcohol or illicit drug use).

• Thyroid diseases.

• Certain medications such as stimulants or corticosteroids.

Mental Health Problems

• Emotional stress.

• Anxiety disorders. 

• Panic disorders.

• Phobias, including somniphobia (fear of sleeping).

• Depressive symptoms.

• Bipolar disorder.

• Post-traumatic stress disorder (PTSD).

• Other psychiatric disorders.

Symptoms of Sleep Deprivation: What Happens If You Only Get 3 Hours of Sleep for One Night?

Physical Symptoms

• Daytime drowsiness or sleepiness

• Fatigue

• Headaches

Cognitive Symptoms 

• Trouble thinking and focusing

• Poor concentration

• Slowed reaction time

• Memory problems

Psychological Symptoms

• Irritability

• Mood changes

Other Symptoms of Severe Sleep Deprivation or Prolonged Sleep Deprivation

• Microsleeps (briefly falling asleep for a few seconds during routine activities and then waking up)

• Ptosis (drooping eyelids)

• Nystagmus (uncontrolled eye movements)

• Speech problems (inability to speak clearly)

• Shakiness (hand tremors)

• Visual, auditory, or tactile hallucinations (seeing, hearing, or feeling things that aren’t actually there)

• Poor judgment

• Impulsive or risky behaviors

What Are The 4 Stages of Sleep Deprivation?

• Stage 1: After 24 hours of going without sleep or poor sleep, the effects of sleep deprivation are similar to alcohol intoxication. 

• Stage 2: More severe symptoms of sleep deprivation, such as microsleeps, problems with thinking and concentration, and impaired decision-making occur during stage 2.

• Stage 3: Severe symptoms such as speech problems and hallucinations develop if sleep deprivation continues. 

• Stage 4: Extreme sleep deprivation symptoms, including hallucinations. 

Short- and Long-Term Health Consequences of Sleep Deprivation

Prolonged periods of sleep deprivation can cause both short- and long-term negative effects on organ systems throughout the body. Some of the health outcomes of sleep deprivation may include: 

• Impaired brain function and cognitive function, including memory, learning, focus, decision-making, and judgment. 

• Increased risk of neurodegenerative disorders such as dementia.

• Increased cardiovascular risk of life-threatening conditions such as heart disease, heart attack, and stroke.

• Increased risk of metabolic syndrome, including hypertension (high blood pressure), hyperlipidemia (high cholesterol), and type 2 diabetes mellitus.

• Higher risk of weight gain and obesity due to the effects of chronic sleep deprivation on hormones such as ghrelin and leptin.

• Poor immune function due to the negative effects of insufficient sleep on the immune system. 

• Increased pain sensitivity.

• Difficulty regulating emotions, mood changes, anxiety, depression.

• Increased risk of mental health disorders that involve psychosis.

• Increased risk of sleep disorders such as sleep apnea.

• Risk of accidents and injuries, for example, due to drowsy driving.

How Many Hours of Sleep Does It Take To Recover From Sleep Deprivation?

You may be able to recover from acute sleep deprivation with one or two nights of enough sleep. However, it can take several days or even weeks of adequate sleep to recover from chronic (long-term) sleep deprivation. 

How is Sleep Deprivation Diagnosed?

Medical Assessment 

Healthcare providers can diagnose sleep deprivation based on your medical history, symptoms, and a description of your daily routine and self-reported sleep duration. This can provide clues to the reason for low-quality sleep or inadequate sleep. 

Further tests may be necessary to diagnose an underlying health condition that might be causing sleep deprivation or to diagnose and treat a health condition that has developed due to sleep deprivation. Your primary care provider can refer you to an expert in sleep medicine if needed.

Tests for a Sleep Disorder Diagnosis

• Polysomnogram: This is a test for obstructive sleep apnea that involves an overnight sleep study in a laboratory done under the guidance of a sleep specialist. The test also records the duration of various sleep stages, such as REM sleep. You can do sleep apnea testing at home as well with a wearable device. 

• Electroencephalogram (EEG): This test records brain activity. It is done to identify any unusual brain activity that might be contributing to sleep deprivation, abnormal sleep patterns, insomnia symptoms, or other sleep problems.

• Actigraphy: This test is done to diagnose circadian rhythm disorders. It is done using a wearable device that records sleep patterns and sleep cycles. 

• Multiple sleep latency test (MSLT): MSLT is a test that can find out if you have excessive daytime sleepiness. It is used to diagnose a sleep disorder called narcolepsy. 

• Maintenance of wakefulness test (MWT): This test checks your ability to stay awake or resist falling asleep. It is done as part of safety evaluations in people who drive commercial vehicles.

Treatments and Management

Can You Fix Sleep Deprivation?

Many people can fix or prevent sleep deprivation through lifestyle changes. This might include maintaining a sleep diary to track the amount of sleep you are getting. It might also involve changing your bedtime routine and eliminating disruptions that prevent you from getting enough sleep. 

Medical Treatments

• Medications: Your healthcare provider can prescribe sleep aids or sleeping pills to improve sleep and help you sleep better and longer. But these medications are habit-forming and therefore only used for the short-term. It is important to identify the underlying cause of sleep deprivation (less sleep or poor quality sleep) and treat it, rather than simply treating the symptom (lack of adequate sleep). 

• Your healthcare provider may recommend other treatments for sleep deprivation, depending on the cause. For example, if you have sleep apnea, you might benefit from breathing support with a CPAP machine or surgery to widen your airway. Pillows, mattresses, and oral appliances are some of the other ways to help you get the recommended amount of sleep and quality sleep every night to prevent negative health outcomes. 

Sleep Hygiene: Recommendations for Healthy Sleep Habits 

• Track the amount of sleep you are getting by keeping a sleep diary or using a smartphone app or smart watch.

• Maintain consistent sleep habits by going to bed and getting up at the same times every day, including weekends.

• Limit screen time and the use of electronics before bedtime. The light from these devices can disrupt your body’s natural circadian rhythm and cause sleep-related problems. 

• Avoid consuming caffeine or alcohol or eating a heavy meal too close to bedtime. Eat a light snack if you are hungry before you go to bed. Avoid rigorous exercise just before or in the hours before going to sleep. However, recent studies show that moderate-intensity exercise does not affect sleep quality and ease of falling asleep as long as it’s completed at least 1 hour before bedtime. 

• Get regular physical activity to promote good quality sleep. 

• Your sleeping environment can affect sleep—both sleep quality and sleep quantity. Make sure your bedroom is cool, dark, and quiet to prevent you from being sleep-deprived the next day. 

• Do not take over-the-counter sleep aids for prolonged periods. Consult your healthcare provider if you have chronic sleep deprivation (reduced sleep duration or low-quality sleep) to find out the cause of sleep loss.

• Consider taking a supplement such as melatonin for short-term sleep deprivation, such as from jet lag or stressful life events.