The Science of Slumber: Delving into Why We Sleep

Book Review & Key Learnings from Dr. Walker’s Bestseller

Why We Sleep: Unlocking the Power of Sleep and Dreams, by Matthew Walker, PhD

💛 Practical, applicable knowledge

💛 Applicable to everyone in the world - we all sleep!

💛 Knowledge is widely accessible, even without a medical degree

👎 Could use more engaging graphics, etc

👎 It’s a lot of information - may be too much to digest in a single read-through

👎 It’s a lot of research, which may be less interesting & engaging for some readers with ADHD

About the Author: Matthew Walker, PhD

Dr. Walker is a Professor of Neuroscience and Psychology at the University of California, Berkeley. He’s also the Founder and Director of the Center for Human Sleep Science. His profile on Berkeley’s site lists an impressive list of features, including CBS 60 Minutes, National Geographic Channel, NOVA Science, NRP and the BBC. On his personal site, you can learn more about the “Sleep Diplomat’s” impressive career as a professor, author, and speaker with his own podcast and newsletter.

"I was once fond of saying, 'Sleep is the third pillar of good health, alongside diet and exercise.' I have changed my tune. Sleep is more than a pillar; it is the foundation on which the other two health bastions sit. Take away the bedrock of sleep, or weaken it just a little, and careful eating or physical exercise become less than effective, as we shall see.”

Sleep: we all need it. Some love it, some resist it. Some can’t seem to catch it no matter how hard they try; others struggle to snap out of it. It’s one of the most common topics of idle conversation - ‘how did you sleep?’ We spend about a third of our life sleeping, and we can’t live without it.

And yet, until recently, no one really understood why.

That’s where Dr. Walker’s book comes in. I discovered Why We Sleep on a recommendation list by Laurie Dupar, Owner and Director of Intrigued, I bought the book on audio (as much as I love to read, it’s just much better to read books with my ears). And I devoured it. I found it relatable, validating, and easily digestible. More than anything, though, I absolutely loved digging into the research. It was fascinating to learn more about what’s going on ‘behind the scenes’ in our brains - and how incredibly important it is for both our physical and mental health.

Favorite Quotes

Why We Sleep is simply packed with valuable information on sleep. Here’s a short bullet list of my favorite quotes to highlight what I learned:

  • “The decimation of sleep throughout industrialized nations is having a catastrophic impact.”
  • To successfully initiate sleep … your core temperature needs to decrease by 2 to 3 degrees Fahrenheit.”
  • “Alcohol is one of the most powerful suppressors of REM [rapid-eye-movement] sleep.”
  • “Melatonin simply provides the official instruction to commence the event of sleep, but does not participate in the sleep race itself.”
  • “Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer.”

ADHD and Sleep Problems: Quick Facts

Come to find out, sleep problems are extremely common for people with ADHD. In fact, up to 80% of individuals with ADHD have sleep problems.

Sleep disturbances were included in the diagnostic criteria for ADHD but were removed from the Diagnostic and Statistical Manual of Mental Disorders in 1980. Even though sleep problems are not included in the criteria for ADHD, sleep problems remain a significant challenge for persons with ADHD. Problems falling asleep, staying asleep, and difficulty waking are common complaints of people with ADHD, and tend to increase as we age.

Sleep issues seem to differ depending on the type of ADHD an individual is diagnosed with. For example, those with inattentive-type ADHD are more likely to have a later bedtime. Those with the hyperactive/impulsive type are more likely to experience insomnia. And (as you might expect) those with the combined type of ADHD are more likely to struggle with both delayed sleep and insomnia.

My Experience With Sleep and ADHD

As I got older and thought I better start working on my sleep health, I realized the odds were a bit against me. I’d been diagnosed with sleep apnea, but felt that the diagnosis failed to fully account for the difficulties I was having, and continued to have even with sleep apnea treatment.

It wasn’t until I was diagnosed with ADHD that I felt I’d finally turned a corner.

I had a late diagnosis. At the age of 32 I diagnosed myself, and did a little looking into it, but ultimately didn’t do much with the information until I received an official diagnosis at age 58. Once I was medicated for ADHD, I slept so much better - and my next sleep study found that the sleep apnea had disappeared.

Why Why We Sleep Matters for People With ADHD

Why We Sleep isn’t written specifically for people with ADHD. But, just like everything else with ADHD, we need to find what works with our brains to get the sleep that our brains need. I really feel this book has so many incredible insights into how and why we sleep that it’s unlikely you’ll walk away with nothing new to try.

The most important takeaway from Why We Sleep is how vital sleep is for our wellbeing - and that we need to be giving it more of our attention when we think about improving our health. In the words of Dr. Thomas Roth, of the Henry Ford Hospital in Detroit, “The number of people who can survive on five hours of sleep or less without impairment, and rounded to a whole number, is zero.” We expect so much out of our brains, but we rarely think about how important sleep is. It’s like expecting our phones, computers, and other devices to function without charging. Sleep allows our brains to reset so they’ll be ready and refreshed for the next day.

Beyond that, Dr. Walker dives deep into the ways that sleep impacts our ability to learn, our memory, decision-making, emotional regulation, and more. If you have ADHD, each of those probably rings a bell - because those are also some of our key symptoms.

Now, I’m not going to claim that every person with ADHD who reads this book will be finally cured of their sleep woes. Nor would I claim that inadequate sleep is to blame for our symptoms. ADHD is, after all, a complex condition. But if you were able to find just a few nuggets of wisdom to help improve your quality of sleep, how much more effective might other ADHD treatments be, with that solid foundation?

Tucking In

We all need good restful sleep so we can live each day to our fullest. Our brains are all unique, and so the treatments are just as unique for each of us. Why We Sleep was one of the keys to discovering what worked for me. If after all these years I can sleep and feel rested, then I know you can find the combination that works for you, too.

Until next time - sweet dreams!

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