For all the lamenting we do about a lack of sleep, none of us really know why it’s a big deal. Therein lies the problem.
Sleep scientist Matthew Walker asks his Masterclass audience: “What percent of the population can survive on 5-6 hours of sleep without adverse effects?”
His answer? Zero.
During his Masterclass, Walker shows the audience a rectangular block called Sleep. Sitting on top, side by side, are two smaller blocks called Exercise and Diet. Without Sleep as their foundation, Exercise and Diet cannot provide you good health. Imagine tree branches suspended in the air without a trunk to support them.
Sleep is the answer to almost everything. And yet, we’d rather swap stories about the latest dermatological procedures for younger-looking skin or drone on about that new fad diet. Why don’t we give sleep the respect it deserves?
Maybe because we don’t know the science behind its profound effect on our lives. So, let’s get educated.
During sleep, waste products are cleansed from your brain
You heard that right. Some yucky ones too, like beta-amyloid, a sticky, toxic protein that builds up in your brain and causes dementia. Luckily, your lymphatic system cleans out this protein every night. But, if you don’t sleep enough, that protein sticks around.
People who consistently get 6 hours of sleep or less a night have a high risk for Alzheimer’s Disease later in life.
Sleep’s most important job is to bolster your immune system
During sleep, your blood pressure lowers. Your heart rate and body temperature go down. Your nervous system moves out of “fight or flight.” Your body goes into a deep, quiet state during which it strengthens and bolsters your immune system. What could be more important?
What’s the big deal about getting off my devices before bed?
Our brains are sensitive to light and darkness. Even though we are no longer living in the 1700s, rising with the sun and finding our way to bed by candlelight, our bodies still depend on light and darkness to know when to get sleepy and when to wake up.
When it gets dark, our pineal gland releases a hormone called melatonin. Melatonin informs us that sleep is coming. However, if we subject our eyes to the light of lamps and screens at night, our brains get confused and melatonin does not get released. Then, we get a second wind and blaze past our body’s natural urge to fall asleep. Once the second wind sets in, we could find ourselves staying up hours later than we intended.
In the morning, the optic nerves in our eyes sense the morning light. This triggers the release of cortisol and other hormones that help us wake up and feel alert.
You don’t want to confuse your body. Help it out by dimming your lights at night before sleep and opening your curtains in the morning when you get up.
If you only make one change in your bedtime habits, let it be this:
Go to bed and wake up at the same time every single day, even on the weekends.
Our bodies have a circadian rhythm, meaning there are times of day when our energy is up and we are alert and times of day when our bodies power down for rest and renewal. Our “chronotype” tells us if we are a morning person, a night person, or someone in between. We cannot change our chronotype. It is determined by our genetic makeup and we must learn to work with it.
Experiment with what time at night you first feel sleepy and honor it by going to bed. Notice what time you feel most alert in the morning. For example, do you find it easier to rise at 6am when you have to catch a flight than to get up at 7:30am on your normal schedule? If so, make adjustments.
Maintaining a consistent rhythm of bedtime and waking is even more beneficial than trying to get closer to your ideal sleeping and waking times. It might take 4-6 weeks to establish new sleep habits but, if you are consistent, you will radically improve your quality of life.
There are two types of sleep and they are both miraculous. Here’s what they do:
1. Non REM
Non REM sleep is a deep state of sleep where newly learned information is taken in and cemented into memory. Sleep scientist Matthew Walker refers to it as the “SAVE” button.
Before learning, we need sleep because it prepares our brain to soak up new information. We need sleep after learning to assimilate the new information and commit it to memory. So, you can see why it is so important for kids who are in school all day to get enough sleep. Walker estimates that only 15% of kids get an adequate amount of sleep. We need to educate kids about sleep, and one of the ways we can do this is by modeling good sleep habits ourselves.
During REM sleep, your brain takes in the events of the day and integrates them. It also processes events from your past that were upsetting to you, thereby healing your psyche overnight. As a result, you often feel better when you wake up in the morning.
REM sleep has another exciting attribute: during REM, we often solve problems that we could not figure out during our waking hours. For example, some people are able to think of a difficult math problem before bed and, upon waking, they have the solution. Or, there may be a personal problem that, after a good night’s sleep, can suddenly be seen from a new angle.
An immense amount of creativity occurs as we dream during REM sleep. For example, Paul McCartney, during a difficult time in his life, said his mother came to him in a dream and said, “Just let it be.” When he woke up, he quickly scribbled down the words to the song that had come to him. Thomas Edison was known to take frequent naps during the day because, when he would wake up, he would have miraculously inventive ideas. He called this phenomenon, “The Genius Gap.”
You don’t need to give up caffeine and alcohol but you do need to drink smarter
Caffeine is a psychoactive stimulant. The timing of when you have it is crucial due to its duration of action. 50% of it is still circulating in your system 5-6 hours later and 1/4 of it is doing the same thing up to 12 hours later, which can definitely interfere with your sleep.
Alcohol, taken at the wrong time and in too large a dose, will also have a negative effect on your sleep. Drifting into light sedation with alcohol is not the same as deep sleep. With alcohol on board, you will wake up many times during the night, creating poor quality of sleep. These brief awakenings will be so fleeting you won’t remember them when you wake up the next day, but you’ll feel sluggish.
If you cannot give up coffee and alcohol, your best bet is to drink early (no coffee after midday, have your cocktail or glass of wine before dinner) and hydrate well afterward.
Sleep deprivation can be dangerous, not only for you but for others
A lack of sleep can be as dangerous as driving while intoxicated. Every month, millions of drivers in the United States fall asleep at the wheel and cause accidents. Roughly 15 percent of all fatal crashes involve a drowsy driver.
Scientific fact: The less you sleep, the shorter your life.
It is widely known that sleep deprivation and sleep disruption is linked to ovarian cancer, breast cancer, prostate cancer, colon cancer, lung cancer and other forms of cancer.
When sleep deprivation was done on mice with cancer, there was a 200% increase in the size and speed of their cancer. A lack of sleep accelerates cancer in humans as well.
Sleep deprivation increases chronic inflammation, stress, anxiety, and cardiovascular disease.
Our immune system needs adequate sleep in order to maintain an effective level of protection.
Sleep yourself fit
Getting more sleep can help you lose excess weight and keep it off. Why? When you are underslept, your body holds onto fat because it thinks it needs it for energy.
Further, our bodies produce two regulating hormones called leptin and ghrelin. When we don’t get enough sleep, the amount of these hormones in our bodies changes dramatically.
Leptin tells us that we have had enough to eat and are satisfied. Ghrelin, conversely, tells us we are hungry, even if we have just had a big meal.
When we are overtired, our leptin stores go down and our ghrelin stores go up, telling us to eat more. When we are overtired, we crave carbohydrates and heavy foods. When we deprive ourselves of sleep, we’re setting ourselves up to eat unhealthy foods and more of them. When we are well-rested, we’re more likely to be drawn to healthy fare like vegetables and salads.
A final interesting fact; the gut microbiomes of people who are underslept look very similar to the gut microbiomes of people who have diabetes or who are overweight. With sleep deprivation, your gut shifts toward fermented species and away from the bacterial-based species you see in the guts of rested people. In people who are underslept, there is usually an excess of cortisol and this negatively affects the health of the gut.
Sugar will sabotage your sleep
Don’t snack on sugar at night or have too much alcohol because the sugar will make your body temperature go up. In order for us to fall asleep and stay asleep, we need our body temperature to go down 1-2 degrees Fahrenheit. Keep your room cool to help this process.
The importance of breathing through your nose during sleep
There are numerous health benefits to breathing through your nose, rather than your mouth, during sleep. During nasal breathing, your nose releases nitric oxide. Nitric oxide is a vasodilator; it widens your blood vessels, boosting oxygen circulation in your body by about 20%. For chronic mouth breathers, there is an easy trick that will switch you over to nasal breathing. Tape your mouth using a durable cloth tape.
At first, place a small strip vertically, starting under your nose and ending just below your lower lip. This is not very constricting and will still allow some air to pass between your lips as you become accustomed to this new kind of breathing. Breathing through your nose at night will produce a deeper, more restful sleep than you ever thought possible.
If you can do maintenance on your car so it runs well, you can find time to sleep
Now that you have a better understanding of why sleep is so important, maybe you will feel motivated to give your body the consistency it needs to keep you happy and healthy for a long time to come.