How Sleep Affects The Brain And Body

How much sleep do you think you need each night? And how much sleep would you say you’re actually getting? If you’re similar to 60 percent of the population, your sleep requirements are not being met. You need more sleep than you’re getting, and though we live in a society that prizes constant motion over sitting still, you may not be able to afford the sleep debt you’re in.

For many people, the busier they are, the better. If they’re not doing something every moment of the day, something is wrong. It seems we’ve been taught to view sleep as a luxury, something for people who have time for it. That’s an unfortunate viewpoint because not only does enough sleep help you act like a decent human being, it helps your body replenish and heal. It is vital to physical and mental health.

Physical pain, stress, hormones, pharmaceutical and recreational drugs, alcohol, chronic illness… these are some of the things that can get in the way of a good night’s sleep. But it’s important to address these factors because sleep is crucial. The quality of our sleep has an impact on almost every system, cell, and tissue. Research shows that chronic sleep disruption increases risk of obesity, type 2 diabetes, depression, cardiovascular disease, and a host of other issues.

What Happens To Your Brain If You Don’t Get Enough Sleep? 

In a lot of ways, how good of a day we have begins with how well we slept the night before. When we don’t sleep so great, one of the first things to go is our mood. Next is the ability to pick up new information or recall details. This may leave us feeling slow, disconnected, “out of it”. Sleep plays a huge part in learning and memory, so it may also be tougher for the brain to store memories from the day so you can recall them later. Sleep helps the brain reset itself so it’s ready for whatever life throws at it next.

As you may be aware, Alzheimer’s disease is the most common type of dementia. It’s associated with memory loss, cognitive impairment, and ultimately, a precipitous decline in the ability to function in daily life. It’s a frightening disease, one that armies of researchers are constantly exploring, trying to get to the bottom of. 

We know that one night of poor sleep can leave us with brain fog the next day, but what does chronic sleeplessness do to our brains? Research has begun to show a connection between waking time and an increased risk of Alzheimer’s disease. Sleep deprivation increases the concentration of harmful plaques in the brain. Studies have also shown that sustained synaptic activity leads to increased beta-amyloid in the brain, a telltale of Alzheimer’s. Does sleep deprivation cause brain damage? It’s starting to look that way.

“For a long time, scientists believed that people with dementia don’t sleep well because their brains are adversely affected by neurodegenerative disease,” says Adam Spira, Ph.D., assistant professor in the department of mental health at the Johns Hopkins Bloomberg School of Public Health in Baltimore, MD. “But researchers have begun pondering whether insomnia might also be a potential cause of cognitive decline rather than simply something that emerges as a result of a neurodegenerative disease.”

What Happens To Your Body When You Don’t Get Enough Sleep? 

If you didn’t rest well last night, it’s not just your brain that pays the price. Proper rest gives your body a chance to recalibrate, just like the brain. Whether you’re a pro athlete, a weekend Crossfitter, or not much into working out at all, you need your body every day. It might need to run a cross-country race, step up to a battle rope challenge, or just make it safely across the street without twisting something, but a healthy body is an important component of living well. 

Though you may not be a marathoner, your body definitely will need to make it through the marathon that is being awake for 16-18 hours, and it requires rest to be ready for all of that. It needs time to repair muscles and joints (from when you almost twisted something), and build up energy. 

Lack of sleep can drain your motivation, making it difficult to get through the day. This means you may end up doing the bare minimum, in work and in other areas, because you’re too exhausted to give it your all. You may end up reaching for too much caffeine, creating a cycle that can be tough to get out of. 

How Much Sleep Do I Need?

Most people require between 7 and 9 hours of sleep in order to function, so what’s right for you is somewhat of an individual thing. But 1 in 3 US adults report that they don’t get the recommended amount of sleep, and that can be detrimental over time. Sleep deprivation can result in serious health problems, and exacerbate existing ones. Every part of the body is helped by quality sleep, and thus every part of it becomes vulnerable with a lack of it. 

Sleep deprivation is the result of a consistent lack of sleep, or poor quality sleep, and may be caused by an underlying sleep disorder.

What Is A Sleep Disorder?

There are more than 80 recognized sleep disorders, a blanket term for a condition that disrupts normal sleep patterns. 

Two of the most common ones are:

Insomnia – An extremely common sleep disorder, Insomnia refers to being unable to fall asleep and stay asleep. It’s estimated that half of all adults experience short term insomnia at some point in their lives, with 1 in 10 experiencing long-term insomnia. 

Sleep apnea – A breathing disorder where a person stops breathing for 10 seconds or more during sleep. It is most often the result of underlying health issues like obesity and heart failure.

Sleep apnea decreases the quality of oxygen your body receives, and increases the risk of high blood pressure, heart attack, and stroke. It can be a vicious cycle because it causes sleep deprivation, which can leave you vulnerable to respiratory infections, colds and flu, thereby exacerbating respiratory issues. 

The Dangers Of Sleep Disorders

Sleep disorders are now recognized as health factors that may increase risk of heart attack and stroke. One study from 2018 showed that sleep apnea in particular is prevalent among those at risk for stroke. Another found people who slept fewer than six hours a night were at a 20 percent greater risk of heart attack.

What Causes Sleep Disorders?

Sleep disorders are often caused by underlying health conditions:

  • Cardiovascular problems, heart disease 
  • Pulmonary issues, lung disease
  • Nerve disorders 
  • Physical pain
  • Mental health woes like depression and anxiety
  • Genetics

What Causes Sleep Deprivation?

Though sleep deprivation is one result of a sleep disorder, sleep deprivation can also be the result of lifestyle conditions and choices. If you’re experiencing sleep deprivation and trying to figure out why, look to poor sleep hygiene, lifestyle choices, work obligations, and other drivers of stress in your life.

While you’re sorting it out, be careful not to overdo it with the coffee or energy drinks. Stimulants like caffeine, sadly, are not enough to override the body’s sleep requirements. They do a convincing job at first, but no. In addition, they can exacerbate sleep deprivation by making it harder to fall asleep later that night. This may lead to a terrible cycle of insomnia, then caffeine, then insomnia… then caffeine.

Bottom line: without enough sleep we don’t function properly, and by most accounts it dramatically decreases quality of life too. Here are the specific ways that sleep affects each of our major systems.

How Sleep Affects The Brain & Body

Central Nervous System

The central nervous system is the information superhighway of the body. This is how you receive and process information from the world around you, including your emotions. Proper sleep serves your central nervous system well by allowing it the time it needs to process what’s been going on. When proper sleep doesn’t happen, more negative emotions and fewer positive ones are a result.

With this understanding, it’s easy to see how chronic lack of sleep can contribute to a mood disorder. One study confirmed that with insomnia, the average person is five times more likely to develop depression. The odds of winding up with anxiety or panic disorders are even greater than that. In a separate study, those with anxiety or depression were found to sleep less than 6 hours a night on average.

When we sleep, our brain indexes information and processes what has been happening to it lately. But when it is deprived of that sleep it becomes exhausted and can’t keep up. This can leave you unable to concentrate, more clumsy thanks to lack of coordination, impatient with yourself and others, prone to mood swings, less creative, and more reckless with decisions. 

Immune System

Just as lack of sleep slows you down, it slows your immune cells down too. All day every day your body is encountering bacteria and viruses, some of which it must protect against. A chronic lack of sleep affects your immune system by changing the way it responds to these pathogens. A healthy immune system will make quick work of everyday bugs and germs, but a compromised one will cause a sluggish response that could make you sick.

If you’re someone who seems to catch every cold or flu that comes your way, you might evaluate your bedtime. Quality sleep can not only put some pep in your step, but it can also keep you in the pink. As we sleep, the immune system goes to work producing antibodies and cytokines that combat the viruses and bacteria we come across each day. When this process is interrupted, we are at increased risk for a host of conditions, some quite severe. It also takes longer to recover from injury and illness.

Digestive System

When people refer to getting their “beauty sleep”, it’s often about how they look… the bags under their eyes, the rosiness of their cheeks. But it turns out sleep can be slimming too.

Studies have shown that people who get less than 7 hours of sleep on average, tend to have a higher risk of becoming obese versus those who get 7 hours or more. The reason for this may lie in the hormones that control appetite known as leptin and ghrelin. Leptin is a hormone that helps you know when you’re full, and ghrelin stimulates hunger. When we’re sleep-deprived, these hormones tend to get out of whack, lowering self control and increasing temptation. Couple this with the lack of motivation that comes with sleep deprivation, and you have yourself a recipe for weight gain.

Cardiovascular System 

Long-term sleep deprivation appears to be associated with increased heart rate, blood pressure, and inflammation, all of which can put extra strain on your heart. This is simply because the less sleep you get, the longer your blood pressure stays up. And high blood pressure can lead to heart disease, stroke, and other problems. 

Quality sleep contributes to healthy blood vessels, blood sugar levels, blood pressure, and inflammation levels too. This is because the body has time to heal from the everyday wear and tear it experiences, repairing and restoring itself right down to the elasticity of its teeny tiny blood vessels.

Endocrine System

Hormones are necessary for our bodies to function, and healthy hormone production is dependent on quality sleep. We’ve already looked at how leptin and ghrelin, two products of the endocrine system, can have a powerful effect on the waistline. But poor or interrupted sleep can also affect growth hormone production, particularly in young people. Growth hormones help build muscle mass, repair cells and tissues, and a whole lot more.

For testosterone production, at least 3 hours of uninterrupted sleep is required, so waking up throughout the night could affect more than just tomorrow, it could affect your fertility.

Studies suggest that people who sleep an average of less than 5 hours nightly have an increased risk of developing diabetes. In the midst of deep sleep, the amount of glucose in your blood drops. If your body doesn’t spend enough time in this place, it’s not enough time for the body to achieve balance – a reset – and as a consequence it has trouble responding to cell requirements and blood sugar levels during the day.

How To Sleep Better

The list of reasons we might experience poor sleep is a mile long, so naturally the list of possible remedies is a mile long too. Taking a look at your lifestyle, sleep environment, health factors, and work situation might help narrow the options a bit. 

Also, it never hurts to experiment. For example, perhaps you’ve never thought much about the 2 cups of coffee you drink every day. But what does it look and feel like if you remove that from your daily routine? It’s not like you can’t add it back in if it doesn’t do what you had hoped. Or what about a morning exercise regimen? What if you started with a morning walk, which has been proven to support good health, and see where it takes you? If you have been sleeping terribly those first few mornings might be rough, but what if you hang on while it works its magic? Give it a month. You can always just stop if it really does nothing for you.

Some ideas to try for better sleep:

  • Limit naps (or avoid them altogether)
  • No caffeine past noon 
  • Wake up at the same time, even on weekends and holidays
  • Go to bed at the same time, even on weekends and holidays
  • No screens for one hour before bed: TV, phone, or computer 
  • Read
  • Meditate
  • Take a bath before bed
  • Avoid heavy meals within a few hours of bedtime 
  • Limit alcohol within a few hours of bedtime
  • Avoid high fat and high sugar foods within a few hours of bedtime
  • No vigorous exercise within a few hours of bedtime
  • Get plenty of natural light during the day
  • Practice good sleep hygiene: keep your bedroom cool, dark, and quiet
  • Reduce anxiety with cognitive behavioral therapy (CBT) and/or relaxation techniques 
  • CPAP (continuous positive airway pressure) machine for sleep apnea while underlying causes are addressed
  • Light therapy
  • Natural products like CBD and melatonin

Quality Sleep = A Quality You

Your best life is one in which your body is well-rested, well-nourished, and running on all cylinders. Each bodily system, and function, is dependent on something else in order to maintain homeostasis: a well-rested, functional, happy you. Though it’s sometimes easy to be thrown off-kilter, with the stresses of work and life, understanding a little about how proper rest informs a more quality existence all-around, can help us to more quickly identify and move toward potential ways to regain equilibrium. 

If you’ve tried certain remedies and are still experiencing poor sleep, consult with a professional.  Most sleep issues can be treated easily and effectively. The whole you depends on good sleep, and attaining this one thing can radiate positive effects throughout your life. You’ll see!


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