Getting by on 4-5 hours of sleep in our culture is seen as a bragworthy achievement. On the other hand, requiring a reasonable 7-8 hours of sleep is considered a sign of weakness. Unfortunately, these perceptions are wrong. In fact, dead wrong—continued or chronic sleep deprivation is cause enough for death, according to sleep science.
The phrase "I'll sleep when I'm dead" is worthy of being the textbook definition of irony. Anyone saying that is unwittingly accelerating their path to the end.
Reconciling wake and sleep
I am a huge proponent of waking up early, having generously touted the benefits of those early a.m. hours. I continue to be an ardent believer in the Brahm-Muhurt or the pre-dawn moments when our energies are primed for creative and spiritual pursuits.
So, where does this new mumbo jumbo about sleep fit in?
According to sleep science, waking up early should only be an option if you can reconcile it with a schedule that lets you get 7-8 hours of sleep a day.
You can attempt to become a 5 a.m. person, but that requires you to not binge on Netflix (or whatever timewasting method appeals to you) until midnight before. You cannot possibly burn the candle on both ends and expect it to be sustainable or productive. An early-wake-up schedule only confers benefits if it is paired with an equal and opposite early-sleep schedule.
Let's understand why.
Why do we need to sleep?
Ponder this. In the millions of years of our evolutionary existence, ostensibly, as the most evolved species, why would evolution still necessitate the body spend eight hours a day, a third of our lifetimes, in a state of unconsciousness and paralysis, when we make ourselves most vulnerable to predators?
The answer is staring right back at us.
Sleep performs critical functions in the preservation of who we are as a species. Lack of sleep in itself can be life-threatening. It is the 8 hours of sleep that directly enable us to accomplish tasks when we are awake. Take away the sleep, and you take away all human achievements and run the risk of complete ruin.
The midnight vacuum cleaner
Picture an office building for a minute. At 6.30 p.m., when employees leave the premises, they also leave behind—in the office—trash bins full of debris (coffee and water cups, lunch wrappers, papers, etc.) Then, the janitorial staff makes their way quietly into the building, after hours, to empty the trash before lining the bins up with new bags for the next day's onslaught.
The janitors cannot clear the trash until you leave the building (so you aren't constantly refilling the bins.)
There are cells in your body, called the glial cells, which perform a similar janitorial function. These cells clean up the metabolic debris accumulated in your brain during the day. But the glial cells lay down one condition before they start work—the debris-clearing will only occur if you are asleep.
Sleep, metaphorically speaking, is you leaving the building—when you physically take a break from conscious activity. The glial cells are like the janitorial stuff spiffing and sprucing your brain, clearing up the toxins, so the brain and body can function well the following day.
Scientists studied the glial system detoxification process in mice through the use of injected dye. The dye did nothing when the mice were awake. However, when the mice slept, the dyes flowed around the brain rapidly—evidence of detoxification in action. Sleep science is clear. The very act of sleeping is essential—a precondition to the waste elimination process.
Why do we need the clean-up to occur in the first place?
Dementia and sleep
One of the toxic proteins eliminated by the glial cells is beta-amyloid. Yes, that infamous hallmark of Alzheimer's disease. Patients with the disease show significantly accumulated levels of beta-amyloid plaques—the proteins that were unable to be cleaned out.
An April 2021 study published in the journal Nature suggests that cutting down on sleep in midlife (the 50s and 60s) is associated with a 30% increased risk of developing late-onset dementia. If that's not sufficient enough sleep science to convince you, how about the following study?
In research published in the American heart association journal in May 2021, the odds of someone developing dementia for those with a family history of the disease were studied. The bad news, you are about 72% likely to get dementia based on your genetic predisposition. The good news, if you adopt at least three healthy behaviors, your risk goes way down. The key healthy behaviors are almost a cliché —sleep, exercise, eat well, limit alcohol, and don't smoke.
Therefore, the duration and quality of sleep are of major significance for the brain to clear built-up waste. So, how can we ensure high quality, 7-8 hours of shut-eye every day? First, let's start with an understanding of what causes us to sleep.
Circadian rhythm is essentially the sleep-wake cycle that makes us humans susceptible to shut-eye at predictable times of the night and (sometimes) day. It is controlled by the hypothalamus in the brain, specifically the suprachiasmatic nucleus (SCN) that receives signals from the optic nerve/retina to regulate the amount of melatonin.
Here's a super simple explanation of how this works:
When the amount of light hitting our eyes decreases, our optic nerves signal our brains to increase melatonin production. This, in turn, triggers the brain to invoke a sleep pattern. Conversely, increased light (as in the morning) reduces melatonin causing wakefulness.
In addition to melatonin, another neurochemical, adenosine, starts to build up in the body from when we are awake. Correspondingly, the pressure to sleep starts to build up too. The longer we are awake, the higher the adenosine level, which, in turn, leads to increased sleep pressure. That feeling of not being able to keep your eyes open for a second longer? That's sleep pressure. The only way to reduce that pressure is to sleep. The very act of sleeping brings the adenosine way down until you are awake again, at which point, the cycle repeats itself.
Of course, this is an overly simplified explanation of sleep science. Other factors include the amount of caffeine ingested in the system, stress hormones, other medications, age, etc., that interfere with the brain's chemistry and sleep regulation.
Unfortunately, our current lifestyles and schedules are at odds with our inherent circadian rhythms. We wake up, work, eat, socialize, and spend our leisure hours on unnaturally flexible schedules, thanks to the availability of artificial light sources. But, something's gotta give, right? The primary casualty—our sleep!
As a result, we are barely functional and resemble walking and talking zombies sometimes. We underestimate the consequences of sleep deprivation.
Lack of sleep impairs us cognitively—we think slower and get into unnecessary arguments. It impacts our judgment and mood and leads to increased stress.
Here is the self-explanatory title of a popular sleep research study on how lack of sleep affects us.
Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication.
In most countries, you break the law when you drive under the influence of alcohol. The consequences are usually severe. We have a barrage of tests to identify DUIs. You wouldn't trust someone drunk to handle a deceased relative's estate settlement or hold a company board meeting.
In a sleep-deprived state, we are exactly like being drunk. Yet, there are no system limitations on our actions. We are free to hold corporate meetings, sign important papers, or drive where we want. We often do all of this and more while wearing our sleep-impaired state like a badge of honor!
So, how can we use sleep science to break this cycle?
Getting adequate sleep
Here are seven pointers to preserve the quantity and quality of your sleep.
1. Wake up and sleep at the same time each day
Avoid social jet lag. Do your best to wake up and sleep at the same time each day.
No kidding. Those days on the calendar, especially the distinction between a weekday and a weekend, is an artificial construct. Your body has no clue whether it is Monday or almost Friday (sorry, that's how I refer to Thursdays.) Your glial cells won't appreciate that you wake up at 5 a.m. for a few days and sleep in till 10 a.m. on others.
2. Wrap-up a couple of hours before bedtime
Metabolically intensive activities such as exercising or eating release cortisol into your bloodstream, which can interfere with the quality of your sleep. It's best to complete such activities 2-3 hours before bedtime to give your bodies a chance to wind down.
3. Avoid emotional triggers before bedtime
Try not to watch or read emotionally triggering content before bedtime. Doomscrolling before bedtime is a recipe for a difficult night's sleep.
4. Take naps. But not too late.
Naps are my favorite guilty pleasure. Ideally, you'd get 7-8 hours of uninterrupted sleep each night. The next best thing is to make up shortfalls with well-timed, quality naps.
In March 2021, a study on the benefits of napping was published. The study subjects were adolescent kids, who are especially susceptible to interrupted sleep patterns thanks to unnatural school schedules. The study proved that splitting sleep between the night and daytime naps was beneficial to kids' memories and helped counter insufficient nocturnal sleep.
So, rather than worry about your teen's 2 p.m. bizarre nap, take comfort in knowing it's helping build her long-term memory (and keeping her off social media.)
But naps are great as long as they are not too long or too late. Excessively long naps or those naps that stretch into the late hours of the afternoon will interfere with your nighttime sleep. Again, going back to our lesson on sleep science, this has to do with the building of sleep pressure. If you release all your sleep pressure through a nap, you'll have to stay awake long enough for the pressure to build up again. It's all about balance.
5. Easy on the caffeine
In my college days, I could drink an espresso at 11 p.m. and fall asleep at 11:05 p.m. Now, my 3 p.m. espresso seems to linger in my brain until 3 a.m. the following day.
For some people, caffeine tends to interfere with adenosine and disrupt sleep.
Moral: Avoid late lattes.
6. Set the tone
Your sleep environment matters. A lot. Cool, dark rooms are conducive to sleep. For some, white noise machines help in getting them to sleep. Others need earplugs. Find out what works for you and stick to it.
7. Find a ritual
If you are like me and wake up thinking about your to-do list at 2 a.m., there's a good chance you'll spend the rest of the night fidgeting. It's helpful then to have a calming ritual or mantra (or count sheep) to stop your mind from buzzing so you can go back to sleep.
This gets better if you are a meditation practitioner. Not that I need any excuse to tout the importance of meditation.
Ancient yogic tradition encourages the practice of yoga Nidra (literally means union of sleep.) This is the practice of getting into a deep sleeplike state while still being in a state of complete awareness. Learning such techniques can help control a spiraling mind.
At 21, Winston Churchill, a man who later garnered the epithet "The Greatest Briton," spent three weeks in Cuba as a war correspondent. Multiple historians point to this adventure as a transformational point in Churchill's life. In addition to honing his skills in areas that eventually made him one of the world's greatest political leaders, Churchill discovered during this stint the power of the siesta.
Siesta is typically an afternoon nap taken after a midday meal in some of the world's hottest regions. This Spanish word originates from the Latin (hora sexta) for the sixth hour from dawn (midday rest.)
From his time in Cuba, Churchill developed the habit of taking a 2-hour afternoon siesta which, according to him, allowed him to fit in 36 hours of work into a 24-hour day.
If "The Man of the Century" could find enough (and more) time to sleep during, arguably, one of the most tumultuous periods in history, I'm sure you and I can manage to find the time too.
There's enough established proven sleep science to show us how critical sleep is not just to avoid brain fog or a bad mood, but for our very survival.
Guard your sleep. Better to beat boredom and blahs with sleep rather than mindless binge-watching or doomscrolling. You will be rewarded with better energy and answers to your most pressing questions when you wake up. No wonder the wise advise us to "sleep on it."