Why We Sleep Summary

1-Sentence-Summary: Why We Sleep will motivate you get more and better quality sleep by showing you the recent scientific findings on why sleep deprivation is bad for individuals and society.

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Why We Sleep Summary

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As humans, we spend a remarkable amount of our lives sleeping. How much? About one-third of our life. So if you live for 75 years, you will spend a staggering 25 years of your life snoozing. But as the world grows busier and more technology-filled, sometimes we consider sleep a hassle.

It seems people try to get the least amount of sleep possible to be able to maximize their busy days. But we shouldn’t underestimate the power of sleep because it’s crucial to our health and well-being. 

In his book Why We Sleep: Unlocking the Power of Sleep and Dreams, Matthew Walker teaches just how vital getting adequate sleep is and what the consequences of sleep deprivation can be.

As a professor of neuroscience and psychology at the University of California-Berkeley and director of the Sleep and Neuroimaging Laboratory, he definitely knows his stuff.

Here 3 awesome lessons I got out of this book:

  1. When you sleep less you increase your chances of heart disease and other health problems. 
  2. You are just as much of a threat to society as a drunk driver when sleep deprived. 
  3. Better sleep comes from following a few simple tips.

Grab a pillow and blanket and let’s learn the how’s and why’s of a great night’s sleep!

Why We Sleep Summary

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Lesson 1: Sleep is foundational to health, and without enough of it your risk of disease increases significantly.

Walker shares that he used to tell people the three pillars for good health consisted of diet, exercise, and sleep. Now that he understands the huge importance of sleep, he tells people that sleep is the foundation that the others stand upon. We all know heart disease is a huge problem around the world. The cost of this increasingly prevalent health problem is a huge burden on healthcare systems. But Walker proposes that the real cure is pretty much free. He says people just need to get more sleep. 

In a 2011 study looking at 500,000 people from various ages and ethnicities, researchers found that sleep deprivation increases the risk of a person getting or dying from heart disease by 45 percent. Another study looking at Japenese men for 14 years found that the workers who slept less than six hours every night were a staggering 500 percent more likely to suffer from cardiac arrest. Even when researchers account for factors that contribute to cardiovascular problems like obesity or smoking, the link remains strong. 

Why is there a link, though? Because a lack of sleep causes a rise in blood pressure. This instance of increased pressure in the veins takes a toll, and eventually, damages the artery walls. This makes you more susceptible to heart disease. So if you want to lower your blood pressure and increase your chances of living a long and healthy life, it could be as simple as getting more sleep!

Lesson 2: If you drive drowsy, you might as well be driving drunk.

We all know of the tragedy that drunk driving can inflict upon not just the driver but also others. But did you know that driving while drowsy is equally as dangerous as driving drunk? So not only is sleep deprivation bad for your health, but it also can make you a threat to society if you get behind the wheel. Getting less than seven hours of sleep per night will increase your chance of getting in an accident considerably. 

When you sleep less than your body needs, it attempts to make up for the lack of sleep by going into a microsleep. Microsleeping is a short bout of sleep that only lasts for a few seconds. It’s the same as normal sleep, just much shorter. So during a microsleep, you don’t have control of motor function. If this is at the wheel, it can only take a two-second microsleep to cause you to drift into another lane and cause a major accident. 

In an Australian study, researchers divided participants into two groups. One drank enough alcohol to increase their blood-alcohol concentration of 0.05, and the other didn’t sleep for a night. Both groups took a concentration test and results showed that those who didn’t sleep for 19 hours did just as poorly as those who were drunk. We all understand drunk driving is irresponsible. But next time you are tempted to drive late into the night, remember that driving when drowsy is also probably just as irresponsible.

Lesson 3: Increasing sunlight exposure during the day and limiting specific substances improves sleep quality.

Walker gives tips based on the latest research on how to improve your sleep. His first tip is to consider avoiding substances like alcohol and nicotine. Having that glass of wine before bed might feel like a great way to end the day and unwind, but science shows alcohol makes it hard for your body to go into a deep sleep.

It can also make it harder to breathe while you’re asleep. And often, people wake up once the alcohol wears off, disrupting sleep. Nicotine is an issue when it comes to sleep because it’s a stimulant. This is why smokers tend to sleep more lightly and wake up earlier because of morning withdrawal. 

Another tip Walker has is to take a hot bath before bed. Taking a bath relaxes your mind as well as your body. The drop in body temperature that you experience when you get out of the bath causes you to experience a feeling of drowsiness, perfect for right before bed. 

We should also try to soak up the sunlight at least a little every day. Natural sunlight helps your body establish and stick to a regular sleep pattern which is why it’s important to get enough. Keep curtains open while you sleep, so that the natural light of the morning sun wakes you rather than an alarm. Lastly, he advises making sure the room temperature where you are sleeping is relatively low.

Why We Sleep Review

Three words keep revolving around my mind after reading Why We Sleep: “threat to society.” I don’t like being negative, but after the research this book presents, that’s the best way I can describe sleep deprivation. The good news, though, is that this book gives some great actionable advice to improve your sleep habits!

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Who would I recommend the Why We Sleep summary to?

The 56-year-old with heart disease who is afraid of dying early and wants to pinpoint what may improve their health the most, the 32-year-old startup founder who is burning the candle at both ends thinking they’re getting ahead, and everyone who thinks they can get by with less sleep.

Last Updated on December 5, 2022

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Luke Rowley

With over 450 summaries that he contributed to Four Minute Books, first as a part-time writer, then as our full-time Managing Editor until late 2021, Luke is our second-most prolific writer. He's also a professional, licensed engineer, working in the solar industry. Next to his day job, he also runs Goal Engineering, a website dedicated to achieving your goals with a unique, 4-4-4 system. Luke is also a husband, father, 75 Hard finisher, and lover of the outdoors. He lives in Utah with his wife and 3 kids.