Sleep is the grand mystery of life. You get sleepy, you yawn, you lay your head down, and then you wake up. At some point, you drifted off to sleep and were unconscious, helpless, completely out of it for the better part of the night. Maybe faint glimmers of the moment before you fell asleep remain in your memory. If you remember your dreams, you've got those to fall back on—but they fade fast. No, for the most part we have no idea what happens when we sleep.
We do know what happens when we don't. The list of maladies caused by and/or linked to sleep deprivation is long and exhausting.
What Happens When You Don't Get Enough Sleep?
The best way to understand why sleep is so important is to learn what goes wrong when you don't get enough it.
Alzheimer's, dementia, and cognitive dysfunction
Insulin resistance and diabetes
Low testosterone
Junk food cravings
Fat gain
Premature aging
Poor immune function
Worsened stress resilience
Impaired antioxidant status
Poor performance and results in the gym
Cognitive dysfunction
Sleep is when the brain does its "house cleaning," where it floods with cerebrospinal fluid to flush out toxins and damaged proteins through channels that widen during sleep.1 If you don't get enough sleep, or you fail to reach the "deep sleep" phase of your normal sleep cycle, your brain can't clear the damage. One night might not be a big deal, but weeks, months, and years of poor sleep where you fail to attain deep sleep will increase your chances of Alzheimer's disease and general cognitive dysfunction.2
Insulin resistance and diabetes
One of the most reliable effects of a single night's bad sleep is an increase in insulin resistance.3 It's such a reliable effect that researchers are always looking for supplements, nutrients, and interventions to counter the insulin resistance induced by bad sleep. Part of this is caused by a reduced ability of the sleepy liver to process fat; if a sleepy liver can't process fat as well, it will accumulate it and turn insulin resistant.4
Low testosterone
A sneaky hack to get a doctor to sign off on TRT for younger guys is to sleep four hours a night for a month leading up to your test. Your testosterone will plummet and the doctor is more likely to sign off on hormone replacement. I don't advise anyone try this, but the fact remains that poor sleep is a great way to lower your testosterone levels.
Junk food cravings
A single night of bad sleep causes people to find junk food more rewarding.5 Patients on no sleep derived more pleasure from food, desired more food, and reported more hunger than patients who had slept. And that was just a single night. Just imagine the effects of days, weeks, or even years of chronic poor sleep.
Fat gain
Sleep restriction increases food intake, particularly snack intake. Moreover, it increases food intake without a concomitant increase in energy output. You eat more without moving more—and it happens spontaneously. Over time, an imbalanced energy intake/output will lead to body fat gain, particularly if you're eating the kind of junk food that poor sleep compels most people to consume.6
Premature aging
The worse you sleep, the worse your skin ages. Sleep restriction is linked to an increase in facial aging and a decrease in skin barrier function.7 Since several studies indicate that the perceived “age of the face” is a better predictor of mortality risk than objective health markers, actual age, or cognitive function, sleep induced facial aging will reflect real mortality effects.8
Poor immune function
When you sleep poorly, you get sick more often. This is true in teens and in adults.9,10 In one paper, melatonin—the sleep hormone your body produces to prepare for bedtime—was one of the only supplements shown to be effective against COVID-19.11 That's no coincidence.
Worsened stress resilience
We've all had a bad night's sleep and then spent the following day trying to fend off stressors that'd usually bounce off us. When you haven't slept much, you're more likely to get into arguments with your spouse and kids, get angry while driving, and snap at co-workers (or total strangers). In short, you are less stress-resilient. That's not just a subjective impression. Objective measurements of stress resilience suffer after sleep restriction.12
Impaired antioxidant status
A single night of sleep deprivation reduces levels of glutathione, the body's premier antioxidant that we use to combat oxidative stress and metabolize and nullify toxins.14 If you've ever had a bad night's sleep, the worst thing you can do is subject yourself to an oxidatively stressful event, like binge drinking.
Poor performance and results in the gym
If you don't get enough sleep, everything involving physical training suffers. Your postural control and balance get worse, leaving you vulnerable to injury. Your actual performance suffers—you don't run as fast or lift as much weight or have as much stamina. And your results aren't as impressive. You don't gain as much muscle or lose as much body fat.
What Are the Benefits of Good Sleep?
A good night’s sleep is the foundation for a healthy, happy, productive existence. Good sleep staves off many of the bad things listed above. And without good, regular sleep, we just go through life in a scattered daze, everything foggy, slightly confusing, and less enjoyable. We’re not really ourselves if we haven’t slept. We desperately need a good night’s sleep, every night.
Sleep is an incredibly active time for our bodies and brains when we undergo all manner of growth and repair processes through a dynamic biochemical orchestration. Sleep is key, essential, absolutely downright necessary for our basic physiological operations.
Good sleep isn’t just about avoiding the negative effects of not sleeping. For one, you wouldn’t be the person you are without sleep. I mean that literally, since sleep spurs the release of human growth hormone (HGH), an essential player in cellular regeneration (and fat burning).
A full night of sleep won't just reduce the risk of brain degeneration, it will enhance your memory performance and creative problem solving skills the next day, not to mention make you a better person to be around by helping you see the positive in your interactions.
A good night’s sleep will further boost your athletic performance, including speed, accuracy, mood and overall energy.14 College athletes who sleep two extra hours per night have more accuracy and faster sprint times.
Good sleep means you dream, and dreams are the way your brain deals with issues your conscious self cannot or will not. That's hard to pin down as "objectively beneficial," as you can't really measure a dream, but the fact that we do dream means it's important—and we should create situations (sleep) that allow us to dream.
How to Get Great Sleep
Great sleep starts in the morning.
As soon as you're awake, go outside and greet the sun. Get natural sunlight onto your body and into your eyes in order to "tell" your circadian clocks that the day has begun and you are awake. The more natural light you get in the daytime, the better you sleep at night.15
Stand barefoot on the earth. Grounding is controversial, but I think there's something to it and studies suggest that connecting to the earth with your bare skin can improve subsequent sleep.
Get some physical activity. Sex, exercise, a little light movement, a barefoot walk outside (which is efficient because it's both light and movement and connection to the earth). The point is to move your body to give your circadian clock the message that you're ready to live the day.
If you eat breakfast, eat plenty of animal protein. You don't have to eat breakfast, although some people find it really helps them get better sleep. But if you do, make sure you're eating protein, as meat-rich breakfasts have been shown to improve sleep.16
Stop caffeine before noon. Caffeine taken after noon has the potential to impact your sleep.
Stop alcohol before 6 PM. The best thing for sleep is to not drink any alcohol at all, but if you're going to drink, having your last one before 6 PM will reduce the chances of any sleep impairment.
Use blue blocking goggles after the sun goes down and/or eliminate the use of screens after dark. Blue light inhibits melatonin secretion and makes it much harder to get to sleep.
Take magnesium or apply magnesium oil to your body before bed. Magnesium is one of the most important minerals for optimal sleep and few people get enough in the diet.
Take collagen or drink bone broth before bed. The glycine in both improve sleep quality and really knock you out (in a good, healthy way).
Keep your room cool. 60-65 degrees is ideal. If you get hot in bed, stick a leg out from under the blanket.
Are Naps Healthy?
A nap is a great way to recover from a poor night's sleep. A nap taken after sleep deprivation is full of REM sleep, more so than the equivalent amount of regular nighttime sleep.17
Furthermore, there are many proven benefits to napping, particularly if you've been skipping sleep:
Napping has been shown to help stave off jet lag.18
A quick nap can be enough to overcome the negative effects of sleep deprivation on learning and memory.
A study in Greek adults found that an afternoon nap was associated with improved heart health and reduced cardiovascular events.
A mere 26 minute nap can boost performance by 34%.
An afternoon nap improves post lunch “cognitive flexibility,” or the ability to multi-task.19
Napping reduces stress, particularly the stress caused by sleep restriction.20
Napping restores immune function impaired by sleep restriction.21
For a truly effective power nap, have a cup of coffee right before you lie down to sleep. You'll wake up with the caffeine in full effect and stave off any sleep inertia.
How Much Sleep Do We Need?
It depends on several variables.
Genetics: Though seven to eight hours is optimal for most people, some genuinely require nine or ten hours. A few lucky ones among us hit our optimum with only six or so hours of shut eye. (These folks are honest to goodness mutants, as science has confirmed.)
Age: However, the majority of our sleep differentiation is determined by age. Babies, no surprises here, need the most (however patchy it is), while adults require the least. The notion that older adults need less sleep is actually hogwash. Although sleep patterns become more fragmented as we age, we still need the same good old average. Sleep still fosters critical hormonal secretion (like growth hormone) necessary for healthy aging. One study in particular linked solid sleep with higher levels of testosterone in older men.22
Children, however, are especially susceptible to the ravages of sleep deprivation. Sleep is essential for babies to learn and retain new information. Sleep deficits have been long been linked to an increased risk of ADHD, depression and behavioral problems in children.23
Exercise: The more and harder you train, the more sleep you need—not only to reap the benefits of your training, but to recover from it. Anyone who demands more from their body will require more sleep.
In today's world rife with responsibilities, early wake-ups, late night disasters, electronic temptations, notifications, work emails, blaring televisions, and glaring lights, sleep can feel like a luxury—or a burden. But sleep is one of the non-negotiables I talk about so much. If you can focus and nail your sleep, make it a sacred component of your lifestyle that you simply do not compromise on, you will reap untold benefits and avoid terrible maladies.
Good night.
References
https://www.sciencedaily.com/releases/2010/05/100505091632.htm ↩
https://www.sciencedaily.com/releases/2008/06/080609071106.htm ↩
https://www.sciencedaily.com/releases/2008/06/080610071936.htm ↩
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* This blog reflects my personal views and opinions and isn’t intended as medical advice, but I hope it will be informative and inspiring as you pursue a healthy, fulfilling life.
Sleep has always been my achilles heel. I have tried every hack in the book and nothing has reliably given me restorative sleep as a norm. I have done so much research and in the end the best explanation was that I was gestated in a high stress hormone environment that has wired me into an almost continuous fight/flight mode of alertness. Of all the hacks really good sound blocking earplugs and a dark room have made the most difference, but are not a cure, just an improvement.