Young woman sleepily resting her face on her hand

5 reasons why you can't sleep

Medically reviewed on August 1, 2022 by Jordan Stachel, MS, RDN, CPT. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

Table of contents

In many ways, your body is like a computer, capable of many vital functions. And like a computer, it needs to recharge for maximum performance.

Sleep is the mechanism by which the body recharges and readies itself for another day. But if you can’t sleep at night, you may find your body is lagging and your brain’s processing speed seriously diminished.

Fortunately, we’re here to explain why you may find sleep such a daunting task and how best to treat sleepless periods. All you need to do is sip a cup of relaxing tea, get cozy, and read on for ways to start counting sheep instead of restless minutes.

Poor sleep habits and routines

Most of us don’t think of sleep as an activity like swimming or baseball, but like all activities, it requires good habits and routines. After all, we know not to swim right after eating a meal, so why would we engage in harmful practices before entering sleep’s tranquil waters?

Most experts agree that sturdy routines build the foundations of sensational sleep. These routines include maintaining a consistent sleep schedule and limiting light exposure before bed. [1]

Conversely, poor sleep routines can cause your foundation to crumble before your dream house can even be built. These less-than-stellar sleep habits include: [1]

  • Consuming certain foods and beverages before bed – Caffeine’s link to sleeplessness is well-known. [2] But what’s less well-known is alcohol’s effect on sleep. While it may seem easier to fall asleep after having a drink before bed, alcohol actually disrupts essential REM sleep, leading to periods of wakefulness. [3] Additionally, foods and beverages containing high sugar levels can lead to glucose spikes, which can, in turn, lead to long nights. [4]
  • Blue-light exposure before sleep – While it may feel relaxing to use your smartphone in bed, the blue light emitted from your smartphone is anything but good news. That’s because studies have shown a connection between blue-light exposure and sleeplessness. [5] You may also want to limit exposure to other blue-light emitting sources, such as televisions and computers, right before bed for better sleep.
  • Having intense conversations before bed – If you’ve ever tried falling asleep while having a lot on your mind, you likely know the feeling of tossing and turning. Emotional, intense, or weighty conversations before bed can burden your brain with thoughts rather than freeing your mind from the day’s stressors.
  • An inconsistent sleep pattern or schedule – Sometimes life is unpredictable. One week you find yourself hitting the hay relatively early and another week you’re a night owl. While some sleep variance is okay, it’s best to maintain a consistent sleep pattern or schedule so that your circadian rhythm stays in tune with your body’s needs. That way, you’ll be able to fall asleep easier and awake less groggy.

Luckily, perfecting your sleep habits and routines isn’t as hard as you might think. All it takes is some dedication and perseverance, and you may soon be well on your way to the Land of Nod.

If you’ve tried everything in the book, such as perfecting your sleep habits and counting sheep until the barnyard is empty, a sleep disorder could be to blame for your sleepless nights.

Sleep disorders are complex. While some may be rooted in bedtime habits, others may be genetic. Common sleep disorders include: [6]

  • Insomnia – Insomnia is a type of sleep problem that is marked by an increased difficulty in falling and staying asleep. Acute insomnia is short-term, while chronic insomnia can last for weeks, months, or years. The exact causes of insomnia are hard to pinpoint, but studies suggest genetics can play a large role. Some may also experience stress induced insomnia, due to increased stress.
  • Sleep apnea – If your snores are louder than an idling diesel truck, your snoring may be more than a minor annoyance—it may also be a sign of sleep apnea. A condition characterized by upper-airway obstruction while sleeping, sleep apnea is one of the sleep problems that can make it difficult to sustain periods of deep sleep.
  • Restless leg syndrome – Restless leg syndrome can make you feel like you’re dancing in a classic ballet even though your bed is the only stage you’re on. That’s because this condition is marked by intense feelings of movement in your lower extremities. While the causes of restless leg syndrome are still poorly understood, studies suggest that genetics may be an important factor.

If you think you might have a sleep disorder, it’s best to consult with your healthcare provider. In most cases, your healthcare provider can prescribe a treatment plan.

That way, you can say goodbye to restless legs and hello to restful nights.


From homemade computers built in garages to the most advanced machines housed at global universities, most computers can slow down if they’re running too many programs. The same holds true for your neurobiology.

During periods of intense work and stress, your mind and body will likely work overtime to manage your obligations. When this happens, you may find it difficult to fall asleep, as your brain simply can’t shut down. [7]

Common stressors that can contribute to insomnolence include:

  • Financial concerns
  • Deaths of loved ones
  • Job loss
  • Health concerns
  • School concerns

Note that cortisol is known as the “stress hormone.” Increased cortisol production can influence the “fight or flight” response, leading to wakefulness. [8]

Mental health disorders

Like sleep-related disorders, mental health disorders can be complex, stemming from several socioeconomic and genetic factors. To complicate matters, the link between mental health and sleeplessness appears to be a classic “chicken or the egg” question.

Do mental disorders contribute to sleeplessness or does sleeplessness exacerbate the risk of developing mental disorders? The answer seems to be yes and yes: sleeplessness can be a symptom of mental health disorders while mental health disorders can arise after periods of insomnia. [9]

Some of the most common sleep-related mental health disorders include: [10]

  • Anxiety – From social anxiety disorders to phobias, anxiety comes in many forms. Among them, sleeplessness appears to be a common symptom. That’s because an anxious brain is typically a hyper-aroused brain. When hyperarousal occurs, it may feel like your thoughts are racing, and sleep becomes a finish line that grows increasingly distant.
  • ADHD – Formally known as attention-deficit/hyperactivity disorder, ADHD is a neurodevelopmental condition associated with sleeplessness, high energy levels, and reduced attention spans—especially in children.
  • Depression – Although many people associate depression with excessive sleep, around 75% of people with depression suffer from periods of insomnia. [11]

Mental health disorders are nothing to sleep on. If you think you might have a mental health disorder, it’s best to meet with your healthcare provider as soon as possible.


As we age, new opportunities may open up. These opportunities can include spending time with grandchildren, traveling the world, and simply relaxing during our “golden years.” That said, aging can also tarnish the gold that is fantastic sleep.

In short, sleep quality tends to decrease as we age. After age 60, people are at a higher risk for developing insomnia and other sleep-related disorders. [12] While several factors may be to blame for this age-related sleep disruption, a melatonin deficiency may be the primary culprit. [13]

Also known as the “sleep hormone,” melatonin helps govern circadian rhythms. Without sufficient melatonin levels, our circadian rhythms become more erratic, leading to sleeplessness. Studies suggest that melatonin levels start to decline after age 40 and hit their lowest points after age 90. [14]

Fortunately, treatments exist to help us age gracefully and well-rested. These include:

  • Bright light therapy
  • Sleep ratio adjustments
  • Cognitive behavioral therapy
  • Medications
  • Physical therapy

With these treatments, you can get the sleep you deserve while experiencing life to the fullest after age 60.

How to treat sleeplessness

If you’ve ever asked yourself, “why can’t I sleep?” you’ve likely also asked, “how can I treat my insomnia or how to fix my sleep schedule?”

The good news is that there are several ways to treat sleepless periods. These methods include: [7]

  • Sleep routine improvements – As stated above, poor sleep habits and routines have been linked to decreased sleep quality. As a result, improving your sleep habits is an easy way to catch more Zs and fewer sleepless nights.
  • Medication – If your healthcare provider determines that your insomnia is linked to sleep-related disorders, they may prescribe medication to help you hit the hay the effortless way. Some medications, like many melatonin supplements, are over-the-counter while others may require a prescription.
  • Cognitive behavioral therapy – Cognitive behavioral therapy, or CBT, is a catch-all term for strategies that help you deal with stress, suppress negative emotions, and find general relaxation. Common CBT techniques include light therapy and stimulus control.

Regardless of your treatment plan, the first step in treating insomnia is discovering the causes of your sleeplessness.

What is melatonin deficiency?

4 ways to handle stress-induced insomnia

Tips on how to fix your sleep schedule


  1. Healthy habits for a better night’s sleep. Mayo Clinic. URL. Accessed August 1, 2022.
  2. Caffeine and Sleep. Sleep Foundation. URL. Accessed August 1, 2022.
  3. Alcohol and Sleep. Sleep Foundation. URL. Accessed August 1, 2022.
  4. Sleep and Blood Glucose Levels. Sleep Foundation. URL. Accessed August 1, 2022.
  5. Blocking nocturnal blue light for insomnia: A randomized controlled trial. Journal of Psychiatric Research. URL. Accessed August 1, 2022.
  6. A Review on Genetics of Sleep Disorders. Iranian Journal of Psychiatry and Behavioral Sciences. URL. Accessed August 1, 2022.
  7. Insomnia. Mayo Clinic. URL. Accessed August 1, 2022.
  8. Cortisol. Cleveland Clinic. URL. Accessed August 1, 2022.
  9. Does improving sleep lead to better mental health? A protocol for a meta-analytic review of randomised controlled trials. BMJ Open. URL. Accessed August 1, 2022.
  10. Mental Health and Sleep. Sleep Foundation. URL. Accessed August 1, 2022.
  11. Sleep disorders as core symptoms of depression. Dialogues in Clinical Neuroscience. URL. Accessed August 1, 2022.
  12. Insomnia and Older Adults. Sleep Foundation. URL. Accessed August 1, 2022.
  13. Melatonin, human aging, and age-related diseases. Experimental Gerontology. URL. Accessed August 1, 2022.
  14. Melatonin. Cleveland Clinic. URL. Accessed August 1, 2022.
  15. We spend about one-third of our life either sleeping or attempting to do so. Handbook of Clinical Neurology. URL. Accessed August 1, 2022.
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