Why Do We Sleep? For More Reasons Than You May Think
Most of us spend about a third of our lives asleep, despite not really having an answer to the question, ‘why do we sleep?’ Now neuroscientists are realizing that sleep is more important than previously thought. They’re also realizing that the worn-out platitude, “you can sleep when you die,” is terrible advice, as that day will undoubtedly come sooner if you short yourself on a good night’s sleep.
You need to be getting seven to eight hours of sleep every night — there’s really no other way around it. And if you think you can healthily get by on less than that, there’s an almost 100 percent chance you’re fooling yourself.
Why is Sleep Important?
While the exact mechanisms of sleep are still being studied, neuroscientists like Matthew Walker, have discovered some interesting learnings about our bodies’ ability to function; what happens when we deprive ourselves of sleep; and the impacts sleep can have on society as a whole.
When we’re awake, Walker says that essentially, we’re causing low-level brain damage. By this he is referring to the build-up of the sticky, toxic junk in our brain, known as beta-amyloid. This accumulation of beta amyloid has been found to correspond with the onset of Alzheimer’s, among many other negative health effects correlated with a lack of sleep.
And sleep is beneficial as more than just a reparatory function, it also replenishes spent resources, and regulates hormone levels that dictate our appetite, cognitive function, and motor skills.
The two hormones that dictate whether we are hungry or full, leptin and ghrelin, have been observed to flare in the opposite direction when we are deprived of sleep. This inevitably leads to an increase in hunger, but even worse, it leads our bodies to crave unhealthy and fattening foods; those with heavy carbs, and less greens. In fact, people who run on four to five hours of sleep per night, tend to eat 200 to 300 more calories per day.
For men, sleep is an important regulator of hormones, most notably testosterone. Sleep deprived males can have the same virility and strength of a man 10 years their senior. For women, a lack of sleep can lead to a significantly increased risk of breast cancer and drops in immune hormones.
According to Walker, just introducing a single night of four-hours sleep among a normal eight-hour sleep schedule, can bring about a 70 percent drop in natural cancer killing cells; the immune assassins that target malignant carcinogens.
Every day our bodies produce these cells and others to fend off disease and maintain our health, and while a cat nap might make you feel refreshed, it won’t make up for the loss of these cells.
Listen to Kat Duff talk about the importance of a good night’s sleep on this episode of Open Minds:
Sleep’s Importance in Learning and Memory
Sleep plays a key function when it comes to retaining everything learned throughout the day and getting better at it. While the sleep when you die phrase is cliché, there’s another truism that actually holds, well, some truth – when you want to solve a problem or get better at something, it’s best to sleep on it.
While some have postulated that the dream state may play a role as a practicing mechanism for our daily life, no one is entirely sure of its function.
However, it has been shown through EEG monitoring that when our brains learn, we essentially create basic algorithms in our head to remember or sequence that function. When we’re awake, initially that sequence is choppy, but through practice and repetition our brain smoothes out the kinks in between.
And this jump happens when we sleep, because our brains continue to repeat those algorithms we’ve been practicing throughout the day. Except it recites them up to 20 times faster. Our brains don’t have to focus on all the other things it does while awake, so it has more bandwidth to devote to developing those algorithms.
Eventually we perform those tasks more fluidly, like when playing an instrument or even doing something as simple as typing. With enough practice, our bodies can perform physical functions without directly thinking about it.
After a single night’s sleep, our bodies show anywhere from a 20 to 30 percent improvement in the skill or function it’s trying to learn. Walker says it’s statistically the greatest performance enhancer of all time.
And this knowledge was used to its advantage in early methods of biohacking by scientists, thinkers, and artists dating back centuries. The micro-nap was used by Aristotle, Einstein, and Tesla, who held onto a pair of steel balls as they nodded off in a chair. When they fell asleep they would drop the balls on the floor or onto a metal pan, waking up from the loud clang. In the seconds, or minute, their brains were asleep, they accessed their creative genius, attributing some of their greatest discoveries to this trick.
For some, this would be exacerbated by first depriving oneself of sleep, not a healthy recommendation, though it goes to show how restorative and impactful sleep can be on the brain.
And if you don’t get enough sleep, your mind will take those micro-naps on its own. Ever been in a room where the lights flicker so quickly that you’re unsure if they even flickered at all? Your brain does that when its tired. It will fall asleep and wake up in an instant. And if you’re incredibly sleep deprived, the brain will get its dream sleep even if you’re awake. That’s why people who have been awake for too long begin to hallucinate – the brain pulls the veil of the dream state over waking reality.
The more we learn about sleep the more we realize how vital it is to nearly every aspect of our health and wellbeing. Unfortunately, there is no way to shortcut getting a healthy night’s rest or making up for it on the weekend. Unlike our metabolic system that can store fat for when its needed later, we can’t store sleep for that reason, we can only accrue sleep debt. So, if you want to live the healthiest life, think clearly, and solve problems, go get some rest.