Not getting enough sleep can have profound and wide-ranging effects on your physical and mental health. Sleep is essential for allowing your body and mind to recharge and repair after a long day. When you don’t get the 7-9 hours of sleep recommended for adults, you put yourself at risk for a variety of short-term and long-term health consequences. In this article, we will explore what happens when you don’t get enough sleep and the various ways lack of sleep impacts your body and brain.
What is considered lack of sleep?
The amount of sleep needed varies slightly from person to person, but general recommendations are:
- Adults: 7-9 hours per night
- Teens: 8-10 hours per night
- Children: 9-12 hours per night
Getting less sleep than recommended on a chronic basis is considered lack of sleep or sleep deprivation. Occasionally getting less than ideal sleep won’t do major damage, but over time it can really take its toll.
Some definitions of different levels of sleep deprivation include:
- Acute sleep deprivation: Getting less sleep than needed for a single night or a few nights in a row
- Chronic sleep deprivation: Getting insufficient sleep on an ongoing basis
- Total sleep deprivation: Going 1-2 days without sleep altogether
Short-Term Effects of Lack of Sleep
Missing sleep for even one or two nights can have noticeable effects on your physical and mental state. Here are some of the short-term effects that start to show up when you don’t get enough sleep:
Fatigue
One of the most obvious effects of shortened sleep is increased feelings of tiredness and fatigue. You may feel like you have no energy and struggle to get through daily activities.
Difficulty concentrating
Sleep is essential for your brain to function optimally. When you are sleep deprived, concentration and focus suffer. You may struggle to stay attentive at work or school.
Irritability
Lack of sleep affects your mood regulation. You may feel more irritable or prone to mood swings when you are sleep deprived.
Reduced cognitive performance
Your learning, problem-solving, and decision making skills get worse with lack of sleep. You may have difficulty thinking clearly or remembering things.
Coordination and motor impairment
Reaction time, balance, and fine motor control can all be impacted by sleep deprivation. You may feel clumsier and have slow reflexes.
Increased mistakes and accidents
All the impacts on cognition and coordination make you much more accident prone when you skimp on sleep. Car accidents, workplace injuries, and medical mistakes become more likely.
Weakened immune system
Lack of sleep compromises your immune system, leaving you more vulnerable to viruses like the cold or flu.
Long-Term Consequences of Insufficient Sleep
Over time, chronic sleep deprivation can contribute to significant health problems. Here are some of the ways long-term lack of sleep impacts your body and mind:
Increased risk of chronic diseases
Insufficient sleep has been linked to higher risk for medical conditions like:
- Obesity
- Diabetes
- Heart disease
- Stroke
- High blood pressure
Research has found sleep deprivation affects hormones that regulate appetite and metabolism, contributing to weight gain over time. It also impacts inflammatory markers, blood pressure, and cardiovascular health.
Impaired brain function
Long-term sleep loss can lead to cognitive decline and neurodegenerative diseases like Alzheimer’s and dementia. During sleep, your brain clears out proteins that build up during wakefulness. Missing sleep prevents this essential brain detox.
Mental health problems
Chronic sleep deprivation is linked to higher incidence of:
- Depression
- Anxiety
- Bipolar disorder
Poor sleep also worsens symptoms of most psychiatric conditions. Healthy sleep helps regulate emotions and stress hormones.
Weakened immune function
Your immune system relies on sleep to function properly and defend against viruses and bacteria. Ongoing lack of sleep leaves you susceptible to frequent colds, flu, and infections.
DNA damage
Groundbreaking research has found lack of sleep can actually damage DNA in your cells, which may accelerate aging and development of cancer.
How Exactly Does Sleep Deprivation Affect Your Body and Brain?
Now that we’ve reviewed the many consequences sleep loss can have, let’s take a look at what is happening in your body that leads to these negative impacts.
Imbalance in brain chemicals and hormones
Many chemicals and hormones in your body follow a circadian rhythm that matches your sleep-wake cycle. When you miss sleep, levels of key hormones like melatonin, human growth hormone, and cortisol are thrown off. This affects your brain function, energy levels, and much more.
| Chemical/Hormone | Impact of sleep deprivation |
|---|---|
| Melatonin | Failure to rise at night leads to low daytime levels, disrupting circadian rhythms |
| Cortisol | Levels spike instead of declining at night, causing inflammation and impaired brain function |
| Human growth hormone | Necessary pulse at beginning of sleep is suppressed, affecting tissue repair and metabolism |
| Ghrelin and leptin | Imbalance in hormones regulating hunger leads to increased appetite |
Reduced brain connectivity
Brain scans show less connectivity between regions of the brain when you are sleep deprived. This impairs cognition, memory, emotional regulation, and more.
Increased inflammation
Sleep loss triggers your immune system, raising inflammatory markers like C-reactive protein and cytokines. Ongoing inflammation damages blood vessels and organs.
Elevated stress hormones
Cortisol and adrenaline remain high when you don’t get enough sleep. This contributes to high blood pressure and heart disease.
Impaired waste clearance in the brain
A 2013 study found your brain’s glymphatic system essentially takes out the trash while you sleep, clearing away proteins and toxins. Missing sleep prevents this essential cleansing process.
Increased appetite and cravings
As mentioned, lack of sleep throws off hormones that regulate hunger. This causes increased appetite, sugar cravings, and unhealthy food choices.
Disruption of gene expression
Recent research has shown over 500 genes are altered by sleep deprivation. Some affect metabolism, immune function, inflammation, and more.
Tips for Preventing Sleep Deprivation
Now that you know the myriad ways insufficient sleep damages your body and brain, let’s discuss some ways to ensure you get enough quality slumber:
Follow a consistent sleep schedule
Going to bed and waking up at roughly the same time each day helps regulate your circadian rhythm. Try to limit variability to under an hour.
Limit blue light exposure before bed
Light from screens suppresses melatonin. Avoid phones, TVs, and computers for an hour before bedtime.
Develop a relaxing bedtime routine
Rituals like a warm bath, light reading, and meditation will prepare your body for restful sleep.
Create a restful sleep environment
Keep your bedroom cool, dark, and quiet. Consider blackout curtains, a white noise machine, and limiting pets.
Avoid caffeine, alcohol, and heavy meals before bed
These can all disrupt sleep quality and duration. Finish eating 2-3 hours before bedtime.
Get regular exercise and sunlight
This helps strengthen your circadian clock so you sleep and wake more easily.
Wind down stress during the day
Anxiety and unresolved emotions interfere with getting good sleep. Practice relaxation techniques and resolve issues before bed.
Conclusion
Sleep has profound effects on nearly every system in your body. Failing to get adequate rest disrupts hormones, brain function, immune health, metabolism, and much more. While the occasional night of poor sleep won’t do major damage, chronic sleep loss puts you at significant risk for medical conditions like obesity, diabetes, and heart disease. Prioritize getting 7-9 hours of quality sleep each night to protect your physical and mental well-being.