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Why can't I sleep? A guide to understand how to sleep better

October 6, 2023
14 minutes
Lifestyle Health & Wellness
Sleep wellness strategies

Sleep is at the top of the list of all the human functions necessary for survival. Sleep's benefits impact every part of our lives; physical health, mental wellness, and emotional stability are deeply ingrained in our sleep patterns.

However, nearly 1 in 3 Americans report not getting the recommended sleep per night — 7 or more hours.

From an increase in digital consumption to mental health disorders, stress, and demanding jobs, there are so many reasons that adults struggle to get adequate sleep quality on a consistent basis.

In this guide, we’ll break down all things sleep. What happens to your body when you sleep, common reasons for not sleeping, consequences of not getting enough sleep, and how you can improve your sleep patterns.

We hope that this guide can serve to answer the question, “Why can’t I sleep?” and support you in taking the necessary steps to improve this essential part of our daily lives.

What happens to your body when you sleep

We know sleep is necessary for survival and supports the body and the mind with daily functions. However, do you know what’s happening inside your body when you’re asleep?

We spend nearly one-third of our lives sleeping, and it’s great to understand what’s going on while you’re catching Z’s. Here are the most critical activities occurring in the body and the brain while asleep.


Scientists and researchers have spent years learning what the brain does while asleep. We know that during sleep, the brain can flush its toxins, and new research shows that memory consolidation also occurs in the brain during sleep as well. From new memories to information processing, the brain is highly active while you’re asleep.

Recovery & Repair

During sleep, the body’s proteins and white blood cells are hard at work to fight off infections and potential diseases. Healing hormones are released during sleep that repair the cells in the body, while an increase in blood flow helps muscles heal and promote cell regeneration.

Energy Conservation

As you go about your day, the energy stored in your body becomes depleted. So, when you go to bed, the cells in your body are hard at work to replace the resources you’ve used to ensure you wake up re-energized, well-rested, and ready to take on the day.

The Sleep Cycles

There are two primary cycles of sleep that the human body experiences while asleep.

The first is rapid eye movement (REM) sleep, and the second is non-rapid eye movement, which is broken down into phases N1, N2, and N3. REM sleep and N3 are considered restorative sleep essential to repairing biological functions.

Each cycle and phase has its own uses and benefits for the body. As you sleep, your body goes through these cycles between 4 and 6 times per night, around 90 minutes per cycle.

REM Sleep

During REM sleep, the brain is the most active during sleep. REM sleep is typically when you dream because the brain has similar activity during this cycle to when you are awake.

Sleep experts believe REM sleep is vital for mood balance, cognitive learning, and storing memories. If you’re having sleep trouble, your REM sleep can also be affected. In the process, you may notice shifts in mood, your ability to learn, and memory issues.

Non-REM Sleep (N1-N3)

During stage 1 of non-REM sleep, bodily functions slow, blood pressure and heart rate decrease, and brain waves slow. Stage 1 is considered when you slowly “nod off” to sleep and typically lasts around one minute.

In Stage 2, body temperature lowers, and two things happen in the brain. These activities are associated with memory consolidation and “neural maintenance,” where the brain can repair itself.

Stage 3 is arguably the most crucial of a night’s sleep — the deep sleep phase. Deep sleep is associated with many critical bodily functions, from releasing hormones to repairing tissue, muscle, and bone. Stage 3 is also responsible for allowing the immune system to regulate.

You may be asleep, but many critical things are happening inside your body and brain!

The Standard Sleep Cycle Length by Age

The older you get, the less sleep you need. But is it really that simple?

Babies and toddlers need the most sleep out of any phase or age. Infants up to one year should be sleeping between 12 and 16 hours per day, while adults require 7 hours at a minimum.

Did you know our sleep cycle durations change as we age?

Newborn sleep cycles are usually around 40 minutes long, while infants are about 50 minutes. Toddlers and young children’s sleep cycles last approximately 60 minutes, while children from 5 to grown adults have sleep cycles ranging from 90 to 120 minutes.

Additionally, babies and children under 5 require nearly twice as much REM sleep as adults. Researchers believe this relates to the brain working hard during REM sleep to consolidate memories and process new experiences.

By the teenage years, sleep cycles and durations are set in stone for the rest of our adult lives. You may experience lighter sleep or more difficulty falling asleep as you age, but in general, all adults need 7 or more hours of sleep per night.

Why Can’t I Sleep? Common Reasons for Not Sleeping

man lying in bed unable to sleep due to insomnia

Not only is a lack of sleep frustrating, but it can also be a slippery slope. That’s why it’s important to determine what factors in your life are causing your sleep disruptions. Once you’ve figured out what it is, you can take the appropriate steps to make lifestyle changes and discuss your options with a doctor.

Existing Health Conditions

A few medical conditions can unexpectedly disrupt your natural healthy sleep patterns without your knowledge. That’s why it’s vital to know how certain conditions may change or interfere with your sleep habits. These health conditions include the following:


Pregnant people often face issues with sleep they didn’t have before becoming pregnant. Insomnia and restless leg syndrome are the most common. Pregnant people also have an increased urge to urinate and nighttime heartburn, which can impact their quality of sleep, particularly in the first and third trimesters.


75 percent of people with depression report having trouble falling and staying asleep. This cycle is particularly challenging because it’s difficult to say which comes first - the depression or the sleep issues.


Insomnia can create difficulties regulating emotions, leading to depression, while depression can impact the duration and quality of sleep, making it difficult to feel better. Those with depression often face excessive daytime sleepiness and may nap to combat their tiredness, which can lead to more issues falling asleep at bedtime.  


Nearly 80 percent of individuals diagnosed with schizophrenia face sleep disturbances on a regular basis. Fortunately, insomnia associated with schizophrenia has been treated quite successfully with cognitive behavioral therapy methods for over 15 years.

Scientists and researchers have determined that overactive dopamine receptors in the brain are likely to blame for insomnia and a lack of restful sleep.

Intellectual/ Developmental Disabilities

Individuals with IDDs, including autism spectrum disorders and ADHD, often have trouble falling and staying asleep. This is likely because people living with autism or ADHD have some difficulties relaxing, preventing their bodies from falling asleep quickly.


It’s no secret that stress can keep us all up at night. When you have things on your mind, shutting them off when it’s time for bed can be difficult. And you aren’t alone in that feeling — 43 percent of adults report that their stress levels regularly impact their sleep quality.

From financial woes, issues at work, or situations with family and friends, there are so many ways that stress impacts our quality of sleep.

Lifestyle Factors

So many lifestyle factors explain why you may not get the sleep you need to function properly. These include:

  • Drinking too much caffeine
  • Alcohol consumption
  • Smoking cigarettes
  • Eating a big meal before bed
  • Not getting enough exercise
  • Irregular sleep schedules
  • Not having a relaxing sleep environment
  • Medications
  • Physical pain
  • Age

Changing lifestyle habits, like consuming large amounts of caffeine or alcohol, and eating before bed, may quickly impact sleep. Others take time to feel the effects, like improving your physical exercise routine and creating consistent sleep schedules.

It’s important to build on consistency and keep going even if you don’t immediately see the desired results. You’re creating lasting healthy sleep patterns that will benefit you throughout your life.

Some of these factors, like physical pain, medications, and age, aren't entirely in your control.  Consulting with a doctor can help you find the lifestyle factors you can control and the ones that can significantly improve your sleep quality. 

Other Mental Health Disorders

If you’re living with a mental health condition like PTSD or anxiety, you may experience poor-quality sleep or chronic sleep issues. People with mental illness may struggle with getting quality sleep, which can, in turn, impact their mental health.

Sleep Disorders

If you’ve been diagnosed with a sleep disorder, you may struggle to get good sleep regularly. Common sleep disorders include sleep apnea, insomnia, narcolepsy, restless leg syndrome, and REM sleep behavior disorder. If you think you may have one of these disorders, consult your physician to get a proper diagnosis so you can figure out how to improve your sleep habits.


Insomnia is the most common sleep disorder that makes it very difficult to fall and stay asleep all night. While most adults experience brief bouts of insomnia throughout their lives, chronic insomnia can be crippling.

Insomnia is most common in women over 60, people with mental health disorders or physical health conditions, and those with irregular sleep schedules. The complications from insomnia include a slowed reaction time and an increased risk of conditions including cardiovascular disease and high blood pressure.

Sleep Apnea

Sleep apnea is a condition where a person’s breathing starts and stops while they’re sleeping. It can be very dangerous because it prevents the body and brain from getting the oxygen they need to function correctly. Sleep apnea is typically diagnosed after the patient completes a sleep study. If they are diagnosed with this sleep disorder, surgery or a breathing device are usually prescribed for treatment.

Signs You Aren’t Getting Quality Sleep

woman yawning at workplace feeling tired from lack of sleep

Some people fail to get quality sleep and hardly realize it. Common signs to watch for that may indicate poor sleep include the following:

  • Daytime tiredness
  • A constant state of grogginess
  • Difficulty waking up and getting out of bed
  • Feeling drowsy while driving or after eating
  • Becoming tired while doing ordinary tasks

The consequences of not sleeping enough

Sleep affects every aspect of our lives, from energy levels to thought processes, mood, and even risk of disease. There are physical, mental, and emotional risks in not getting enough sleep, all of which can be lowered significantly by getting to the root of the problem.

Physical effects

Not only is it critical to get consistent sleep, but getting enough deep sleep is vital for our physical health. Individuals who fail to get enough deep, restorative sleep are more at risk for cardiovascular disease, diabetes, infection, depression, and obesity.

As we discussed, necessary replenishment, repair, and recovery tasks occur in the body when we sleep. The physical effects and risks can be severe over time if the body doesn’t get adequate opportunities to repair itself. The cumulative impacts include an increased risk of the following:

  • Hypertension
  • Obesity/ weight gain
  • Type 2 Diabetes
  • Heart attack
  • Stroke
  • Respiratory infections (cold, flu)
  • Inflammation
  • Low sex drive

Additionally, a lack of sleep can impact your balance and coordination, making you more prone to accidents. When you aren’t getting enough sleep, your body will be more tired, making it more challenging to have the energy to exercise. This can impact your ability to maintain a healthy weight because your body builds up insulin resistance with less physical activity.

Mental effects

The mental effects of sleep deprivation can be just as harmful as the physical risks. Here are the troubling mental effects you may experience if you’re struggling to get enough sleep:

  • Lack of concentration and focus (often called brain fog)
  • Decreased alertness
  • Decreased creativity and motivation
  • Poor problem-solving and decision-making skills
  • Confusion, stress, and anxiety

Emotional effects

Most people are grumpy and irritable after a night of inadequate sleep. When sleep deprivation or insomnia becomes a consistent issue, the emotional effects can be overwhelming. Some changes you should look for include:

  • Trouble coping with change
  • Lack of emotional and behavioral control
  • Severe mood swings
  • Impulsive or risk-taking behavior

What can I do to sleep better?

Mature senior man sitting on floor practicing guided meditation at home, relaxing body and mind before sleep

Are you wondering how to get more deep sleep and better sleep overall? You can combat poor sleep and get back on track in many ways. Here are some of the most effective ways to fall asleep and get better quality sleep in the process.

Relaxation techniques

Relaxation techniques are designed to do just what you’d think - help you relax! Relaxation techniques can be very effective if you need help managing daily stress that doesn’t seem to ease before bed.

Breathing exercises

Breathing exercises are a great way to manage stress, promote relaxation, and help you find peace and calm before you head to bed. The most effective breathing exercises can also promote the production of melatonin, which aids with sleep as well.

4-7-8 Breathing, known as relaxing breath, involves a deep inhalation, holding the breath, and then slowly exhaling. You should inhale for a count of 4, hold your breath for a count of 7, then exhale for a count of 8.

Belly breathing teaches slower, more intentional breaths with the end goal of relieving stress and anxiety. Take deep breaths through the nose and exhale through the mouth, with a hand on your chest and another on your stomach. Taking your time, inhale up to 20 breaths until you feel more relaxed.

Box breathing is a helpful strategy for visual learners who need something to picture while focusing on breathing. This involves picturing a box and its four sides as you take four deep breaths in to calm your thoughts. As you envision your box, slowly inhale for a count of 4, then hold your breath for 4. Then, exhale for a count of 4, and finally, hold your breath for another count of 4.


Meditation is used around the world to promote calmness and mindfulness, two powerful feelings to foster before bedtime. The health benefits of meditation are robust for sleep in particular.

Meditating before bedtime can increase serotonin levels, encourage slower breathing, reduce heart rate, and lower blood pressure. It can also reduce adrenaline anxiety, preventing you from feeling tired. These are essential for a positive sleep routine, so we highly recommend meditation as part of your pre-bedtime ritual.


Through intentional mindfulness practices, you can focus on the present rather than being distracted by anything that happened during your day. Mindfulness is designed to help you relax, be aware of your body and feelings, and find peace through grace and acceptance. Mindfulness is usually practiced during meditation, but you can begin by associating sleep with positive energy and accepting that you’re doing what you can to improve your sleep patterns.


Consider adding some light yoga stretches to your bedtime routine to help you wind down for the night. Yoga is associated with lowering cortisol, the stress hormone, in the body, allowing you to de-stress and find calm at the end of the day.

Get regular exercise

Aside from yoga before bed, you should exercise regularly to combat sleep deprivation. Physical activity releases endorphins into the brain, which improves mood and decreases anxiety and stress. We discussed the deep sleep phase at great lengths, and studies have shown that physical exercise can help enter and prolong the deep sleep phase.

Limit caffeine

If you can’t get through the day without several cups of coffee, it may be time to reevaluate your caffeine intake and find other ways to feel energized. Caffeine positively impacts mental alertness, performance, and mood, but it can also take the body a long time to process, affecting sleep quality and duration.

Are you not ready to give up your daily caffeine? Try to limit your caffeine consumption to under 400 mg per day, and avoid it entirely in the late afternoon or evening. This is about four cups of coffee, six cans of soda, and eight cups of black tea.

Establish a bedtime routine

Creating and sticking to a consistent bedtime routine will help to improve your sleep habits. Routines are personal, but here are a few standard things to do in order to wind down in the evening.

  • Turn down the lights
  • Turn off the TV and put your phone away
  • Take a shower or a warm bath
  • Take melatonin 30 minutes before bed
  • Read a book or talk to your spouse
  • Complete some positive affirmations
  • Stretch, do yoga, or breathing exercises
  • Drink some caffeine-free tea or water

Create a relaxing environment

Invest in a firm but comfortable mattress, black-out curtains to shield any light, and try a white noise machine to drown out any environmental noises or distractions.

If you have chronic pain, it’s worth investing in a quality pillow that will help with your alignment and ensure you don’t wake up sore from sleeping in an uncomfortable position. Be sure to remove any electronics that may distract you or leave you feeling unsettled before bed.

Avoid daily naps

You may love taking naps during the day. Unfortunately, long, frequent naps can have a negative effect on sleep quality overnight, particularly if you struggle with insomnia or haven’t been sleeping well recently. Avoid napping for a week or so, and then evaluate if your sleep has improved.

Get better sleep and improve your health

Now that we’ve answered the question, “Why can’t I sleep?” It's your turn to explore the lifestyle factors and possibilities that could impact your sleep and, in turn, your quality of life. If you're concerned you're not getting enough quality sleep, consider speaking with a healthcare provider or participating in medical research or a sleep study to get answers.

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