This year for lent my wife and I decided to wake up an hour earlier to see the sunrise. Every day for 40 days. We had been missing the beautiful tropical sunrise and wanted to take advantage of living by the sea in Puerto Rico. If we were getting up an hour earlier that would mean we should go to bed an hour early. For us, that’s 10 pm. That’s a pretty early bedtime unless you’re in a rest home. I had forgotten why sleep is so important.
It got me thinking about how society views sleep. For waking up early and probably getting less sleep, I’d get 2 gold stars from society. The first, for being an early riser and a go-getter. For some reason, most people view getting up early in a much more favorable light than staying up late, even though scientifically, they both have advantages as far as productivity.
The second gold star is for not needing as much sleep. Nearly everyone thinks they don’t need as much sleep as they really do. I’m sure you’ve heard phrases like, “I’ll sleep when I’m dead” or “You snooze, you lose.” The implication is that motivated and active people don’t sleep. They’ve got stuff to do.
Some people are famous for not needing much sleep. People like Leonardo da Vinci and Nikola Tesla. When asked how much someone needs, Napoleon is quoted as saying “six hours for a man, seven for a woman, eight for a fool.” There are plenty of modern people who try to impress us with their lack of shut-eye. They always say things like, “my body just doesn’t need a lot of sleep (like all you stupid idiots).”
However, if it wasn’t important then why would humans have evolved to spend 1/3 of our lives doing it? Especially considering all the downsides. When our ancestors were asleep they were not hunting, eating, looking for food or looking for a mate and were vulnerable to predators. If there were no benefits, that’s a terrible use of time!
It’s the same for us today. Don’t buy into the hype that you can “get by” on just dozing a little here and there. Science has proven that’s false.
Students and corporate employees work in a culture than encourages, and sometimes requires, working long hours into the night and sometimes all night. When I worked on Wall Street, the culture required working all hours of the night. You were mocked if you went home before 6 pm. People would yell out to you as you snuck out the door, “so, working a half-day, eh?” That’s why caffeine and hard drugs like cocaine can be prevalent in those high -pressure environments. (I didn’t use either. Hot chocolate is as hard as I go.)
Sleep plays an important role in learning and retention. The process of acquiring knowledge has 3 steps:
Consolidation happens only when we sleep, so when that is disrupted, the ability to learn and remember is reduced. One study tracked students studying a foreign language and found their REM sleep (or deep sleep) increased during a period when they focused on studying. This suggests that REM sleep is very important in the consolidation of complex information.1 If you sleep less, you’ll remember less of what you learned during the day.
If we don’t get enough shut-eye, the acquisition of information is also affected because we can’t focus and may be in a bad mood and the neurons in our brain don’t function as well when trying to retrieve information stored in our brains.
Maybe even more important than acquiring and accessing information is our ability to think. Our judgment is affected by sleep and we make stupid decisions when we’re tired.
If you’re studying for a test or preparing for a big presentation the next day, then not getting enough sleep is one of the worst things you can do. During sleep, our bodies are just as active, and our brains possibly even more active, than when we’re awake. It’s a time for our brain to transfer memories from short-term to long-term storage in a process called “consolidation,” mentioned above.
In addition, our bodies need sleep to rejuvenate and repair from the day’s activities. In fact, studies have shown that major restorative functions in the body like muscle growth, tissue repair, protein synthesis, and growth hormone release occur mostly, or in some cases only, during sleep.”2 Babies should sleep about 12-15 hours a night and about half of that time is spent in REM sleep. It is thought that it’s because they spend so much time growing and learning that sleep helps with both memory retention and building of the body.
It’s a common belief that adults need 7-9 hours of sleep. Kids even more. That’s true. 3 What’s not commonly known is that you can’t really “catch up on sleep” other than in the very short-term. If you go a few days with inadequate sleep, the damage has already been done. You can’t repay that debt. In short, we need sleep to function properly and going without enough of it for long periods does damage you can’t recover from.
There are 3 reasons our bodies sleep:
During our waking hours, a chemical called adenosine builds up in our blood. When we sleep our body breaks down the chemical. As the adenosine builds up it tells our body that we must sleep and our body starts doing everything it can to fall asleep, which can lead to all sorts of problems if you’re driving, trying to work or trying to concentrate on class or cram for a test.
Stay up for 24 hours and your response time would qualify to be legally drunk in every state in the U.S.
Our circadian rhythm regulates how our body operates, when it rests and when it’s active. Having a good, consistent circadian rhythm has a lot of health benefits. Throw off that rhyme and things become more difficult in a lot of ways.
External queues like light and sound influence your sleep. Light signals coming through your eyes tell your body that it’s daytime and time to be awake. When it gets dark your body releases a chemical called melatonin, which helps you feel drowsy. That’s why it’s recommended to not be around screens (TV, phones, computer) for an hour or so before bedtime. As the sun rises your body releases cortisol to wake you up.
A while ago I heard of people advocating for high schools to start later and I thought it was an interesting idea. The scientists argued that teenagers sleep more and wake up later. I thought that was just teens being lazy, but it turns out the research supports this. As we age, we go to bed earlier and wake up earlier. 4That’s why you see all those old people out walking at 5 am and not a teenager in sight for miles.
Not getting enough sleep has been linked to “many chronic health problems, including heart disease, kidney disease, high blood pressure, diabetes, stroke, obesity, and depression,” not to mention the added risk of being sleep deprived while trying to function all day. 5
The common perception is we can learn to get by with little sleep, but science has proven otherwise. Lack of sleep will get you and mess with your happiness, physical and mental health, and emotional well-being.
Not sleeping affects your health. There’s a direct correlation between losing nightly sleep and becoming obese. In addition, sleep deprivation may make you feel more hungry and lead to more eating. This happens because the hormones that make you feel hungry (ghrelin) or full (leptin) get out of whack. The hormones that promote growth and muscle restoration can also become imbalanced. Your immune system and blood sugar level are also compromised if you don’t get enough sleep.
If you’re not getting enough sleep and creating a “sleep debt,” that debt must be repaid. If you continually fall behind each night, it’s tough to recover and you may not be able to catch up. You can’t catch up on 20 hours in one weekend.
Have you ever been driving and realized that you haven’t been paying attention for a while? It’s a scary thought. Or been listening to someone talk and realize that you’ve zoned out and haven’t heard anything they said. It’s likely that you experienced “microsleep.” Your brain briefly goes to sleep to try to catch up. The risk can range to embarrassing to very dangerous, depending on what you’re doing at the time it happens.
So if you want better health, a better mood and higher performance, get 7-9 hours of sleep and don’t believe the hype that high performers working around the clock can get ahead. It’s a myth. The strong performers, whether using their brains or bodies, outdo everyone else because they focus on long-term results and sleep is a big part of that.
Related: Everything I’m doing to increase healthspan and lifespan