What Makes for a Good Night's Sleep?

We all have to do it, and without it we wouldn't survive. You may be under the false impression that your body and mind just “turn offâ€‌ at night, but that couldn't be further from the truth. It has actually taken quite a lot of scientific research to understand what's going on when we sleep, with new discoveries being made all the time. We are only now learning more about the ways that sleep affects our physical and mental health and our ability to function while awake.

You probably know that there are several “stagesâ€‌ of sleep, during which we experience different critical biological processes. Every night, we travel through each of these important periods, and we must spend adequate time in every stage in order to maintain wellness and feel rested in the morning.

Let's look at the journey of sleep we take every night and how the four stages fit into a healthy regenerative cycle. We have three stages of non-rapid eye movement (NREM) sleep, followed by one stage of rapid eye movement (REM) sleep. It takes about an hour and a half to go through all four stages, and a good night's sleep consists of moving through this complete cycle several times.

Here's what happens in one of these cycles:

NREM1: Slipping into sleep. Your brain waves begin to slow as you ease into the first relaxing stage of sleep. You are entering a very light sleep from which you can be easily awakened. Your eyes move slowly, muscles relax, and your heart rate and breathing slow down.

NREM2: Light sleep. There is a notable drop in your body temperature, heart rate, and blood pressure. Your eye movements cease and your brain waves slow way down, with occasional bursts of rapid waves.

NREM3: Deeper sleep. Your brain waves slow down even further. Now that you are in deep sleep, it's more difficult to rouse you. In this stage, much healing and regeneration occurs, including the repair of tissue, new cell growth, and the buildup of your immune system, among other things. If you don't spend adequate time in this stage, you will not feel well rested in the morning.

REM: Rapid eye movement sleep. About ninety minutes after falling asleep, you reach REM sleep. In this stage, you dream. Your eyes move rapidly beneath closed eyelids and your heart rate and blood pressure may rise, yet your muscles are temporarily paralyzed to protect you from acting out your dreams. This stage is important in learning, processing, and sorting information.

Research indicates that we get the greatest health benefits in NREM3 and REM sleep. If we don't get enough sleep during the course of the night, we miss out on the regenerative and protective processes of these stages, thus setting ourselves up for dysregulation and disease.

Dangers of Disordered Sleep

Whether you have worked night shifts for years, struggle with occasional sleepless nights, or just decide to stay up another hour to finish a few things you want to do, losing sleep leads to profound health-related complications. If you avoid going to sleep because you think it's wasted time, you couldn't be more mistaken. Whatever work you do in the extra hours you stay awake will be slower and less productive, and it will come at the cost of your overall health. The cognitive loss you experience in sleep deficit is similar to having a blood alcohol concentration over the legal limit for driving. 

Despite the very real dangers of not getting enough sleep, however, our contemporary culture seems to encourage it. We are conditioned to be proud of not “needingâ€‌ more than a few hours of sleep; we're told that this makes us hard workers, dedicated to our professions, or admirably unwilling to miss a single moment of our lives. We may repeat phrases like, “I'll sleep when I'm dead,â€‌ or “Sleep is for the weak.â€‌ An entire energy drink industry exists in intimate relationship to these false ideas about sleep and profits from keeping people up when they should be resting. The fact is that sleep is a fundamental human necessity, not a weakness, and sleep deprivation is not a sign of our dedication—it's a sign that we are overworked, overstressed, and damaging our health. I want us to stop celebrating people who sacrifice sleep, as sleep deprivation puts everyone at risk.

Insomnia is the most common sleep disorder reported by Americans and characterized by chronic difficulty falling asleep and/or staying asleep. Many factors may contribute to this, including stress, physical pain, depression, drugs, alcohol, and even some medications. Of course, we all on occasion experience trouble sleeping—that's normal. We call it insomnia when this issue goes on for three months or more. This condition can be treated and must be brought to the attention of a physician. Please do not delay seeking care from a health-care professional if you are experiencing ongoing sleep deprivation. The overview of sleep in this chapter will help you have a meaningful conversation with your doctor to get the best possible treatment plan.

In addition to insomnia, the other most common sleep issue I see in clinical practice is obstructive sleep apnea (OSA). Sleep apnea is a category of conditions related to irregular breathing during sleep. OSA is often related to obesity, as increased fat deposits around the tongue and throat restrict airflow, resulting in lack of oxygen and awakening from sleep. Many patients may not be aware that anything is wrong, and often the first clue comes from their sleep partner, who reports loud snoring with periodic frightening episodes when the individual appears to stop breathing. OSA may be present in almost half of those with a BMI greater than 30. This is sobering, since the most recent obesity rate reported by the CDC is 42.4 percent. 

This equates to many millions of Americans suffering from OSA. This condition is treatable and manageable, but the diagnosis needs to be made to prevent complications like heart disease and increased risk of motor vehicle accidents.  If you snore and/or experience daytime drowsiness, please bring this to the attention of your doctor for an appropriate evaluation.

Beyond these leading sleep disorders, I encounter patients dealing with restless legs syndrome, narcolepsy, sleepwalking, bed-wetting, nightmares, and more—all of which can complicate effective sleep hygiene. Whenever a patient is having trouble sleeping, it is important to take a detailed history and complete a thorough physical exam to fully understand what is contributing to this disruption.

In a recent case, a patient presented to me with what he described as inexplicable alertness and nervousness over six months, which was interfering with his sleep. In working with him further, I made a diagnosis of hyperthyroidism. Once we treated his overactive thyroid, his sleep cycle normalized. In another case, a patient was sleeping nine to ten hours, which is more than normal. Her blood work revealed she was suffering from iron deficiency anemia from uterine fibroids. Once her fibroids were managed by her gynecologist and iron stores were replenished, she reverted to a healthy regenerative sleep cycle. I share these examples to dissuade you from ignoring any sleeping problems you may be experiencing, as so many people do for years, and tell your doctor about them instead.

For all of us, it's not just the quantity of sleep that is important, but the quality of sleep too. That is, you might stay in bed for seven or eight hours a night without ever fully going through all four sleep stages. Inadequate or poor-quality sleep has been linked to several chronic diseases including heart disease, type 2 diabetes, stroke, obesity, and depression. 

There is even evidence that poor sleep habits like those practiced by irregular shift workers could contribute to cancer risk.  In a study published in 2013, investigators concluded that female night shift workers were at a 30 percent increased risk of breast cancer.  This might be due to the disruption of normal circadian rhythm (another name for our internal biological clock). Being in a light-filled environment at night suppresses the release of the chemical melatonin. Melatonin helps us feel sleepy and fall asleep naturally. When this cycle gets disrupted long term, it can be hard to get a good night's sleep. That's why turning off all the lights in your bedroom may be one of the simplest and most important things you can do to improve the quality of your sleep.

Sleep disorders are indeed a global challenge, with Americans experiencing more trouble sleeping than other cultures. An international survey conducted more than a decade ago showed that 56 percent of people surveyed in the United States reported sleep problems, compared to 31 percent in western Europe and 23 percent in Japan.  Over half of Americans aren't sleeping well, and even if they know the health and safety dangers, very few folks ask for help from their doctors. When they do, physicians most commonly treat the sleep complaint with a prescription. Sound familiar? By now you know that there is often a better way than the prescription pad to address the root causes of chronic conditions through simple, profound lifestyle practices that elevate virtually every measure of health and well-being.