New book from NYT bestselling author Lewis Howes is now available!

New book from NYT bestselling author Lewis Howes is now available!


Dr. Matthew Walker

Why We Should Prioritize Sleep & Understanding The Impact of Dreams (Part 1)


Have you ever woken up cranky even after you thought you had a good night’s sleep? It’s frustrating — especially when you’re working tirelessly to pursue your goals. 

The American author and motivational speaker, Zig Ziglar perfectly describes the importance of goals by saying, “What you get by achieving your goals is not as important as what you become by achieving your goals.”

Sleep is the foundation we give ourselves to pursue our goals vigorously, and today’s guest is perfectly suited to help us understand why we should be prioritizing our sleep. Dr. Matthew Walker earned his degree in neuroscience from Nottingham University, UK, and his Ph.D. in neurophysiology from the Medical Research Council in London. Dr. Walker researches the impact of sleep on human health and disease, and he’s written the international bestseller, Why We Sleep, unlocking the power of sleep and dreams.

Today’s episode was so powerful that I want to split it up into two parts with the second half of this episode coming out later this week. You do not want to miss it!

In this episode, we discuss why sleep is the foundational pillar for our overall health, why most people are terrible at prioritizing sleep and how to change that, the effects of poor sleep over time, how anxiety and stress affect our sleep, the importance of dreams and how we can influence them, and so much more. 

Who Is Dr. Matthew Walker?

Dr. Walker earned his degree in neuroscience from Nottingham University, UK, and his Ph.D. in neurophysiology from the Medical Research Council in London. He later became a Professor of Psychiatry at Harvard Medical School. Currently, he is a Professor of Neuroscience and Psychology at the University of California. He is also the founder and director of the Center for Human Sleep Science

Dr. Walker’s research examines the impact of sleep on human health and disease. He has received numerous funding awards from the National Science Foundation and the National Institutes of Health and is a Kavli Fellow of the National Academy of Sciences

Dr. Walker is the author of the international bestseller, Why We Sleep. It has a singular goal: to reunite humanity with sleep. The book provides a complete description of, and prescription for, sleep. It answers critical questions about sleep: How do caffeine and alcohol affect sleep? What really happens during dreaming? Why do our sleep patterns change across a lifetime? How do common sleep pills affect us and can they do long-term damage?

Dr. Walker is also hosting the new podcast, The Matt Walker Podcast, which is all about sleep, the brain, and the body.

I’m excited about having Dr. Walker because as a former athlete and someone who’s always wanted to perform at high levels in business, I’ve been obsessed with the topic of sleep and creating sleep sanctuaries. 

Let’s jump right in!

How Poor Sleep Impacts Brain Chemistry

It’s hard to understate the importance sleep plays in our lives, but if we do sleep poorly — how does this impact our brain? 

“Sleep is probably the single most effective thing that you can do to reset both your brain [and] your body’s health. I don’t say that flippantly against the notions of diet and exercise — both of those are fundamentally critical — but if I were to deprive you of sleep for 24 hours, deprive you of food for 24 hours, or deprive you of water or exercise for 24 hours, and then I were to map the brain and body impairment you would suffer after each one of those four — hands down a lack of sleep will implode your brain and body far more significantly.” – Dr. Matthew Walker

Good overall health is usually spoken about in terms of diet and exercise, but hardly any focus is given to sleep, which, according to Dr. Walker, is the foundation on which those two other things sit. If you’re not getting sufficient sleep, diet and exercise tend to be far more futile as a consequence.

Somewhere between seven to nine hours of sleep for the average adult is what’s recommended because once you go below seven hours of sleep, you can start to measure objective impairments in your brain and your body. 

Dr. Walker uses baseline measurements of different operations of the brain like cognition, attention, learning, and memory, as well as monitoring mood, emotions, and anxiety for sleep deprivation. Linking this to your cardiovascular system or your blood pressure, he’s able to measure your immune system too. 

“I can measure this sort of kaleidoscope of health metrics on Lewis Howes and then see when I keep dialing you back with less and less sleep — at what point do I see at least one of those things demonstrating a breaking point? It’s very rare for us to be able to find any individual who can go below six hours of sleep and not show some kind of impairment. – Dr. Matthew Walker

In a study, Dr. Walker took a group of perfectly healthy individuals and limited them to six hours of sleep a night for one week, and measured the change in their gene activity profile relative to when those same individuals were getting a full eight hours of sleep at night. 

There were two critical findings. The first was that 711 genes were distorted in their activity caused by that one week of short sleep. 

“What I found most interesting was that about half of those genes were actually increased in their activity [while] the other half decreased. Those genes that were suppressed were associated with your immune system, so you became immune-compromised or immune-deficient. Those genes that were increased in their activity, or what we call overexpressed, were genes associated with the promotion of tumors, cardiovascular disease, and stress and with long-term chronic inflammation within the body.” – Dr. Matthew Walker

Many people have a genuine concern about genetically modified embryos or even genetically modified food, but few give thought to what happens when we don’t get sufficient sleep — that we are unwittingly performing a genetic manipulation on ourselves. 

There might be hordes of people unwittingly harming their bodies by sleeping less than six hours every night. The big question is — besides the time we spend sleeping, what else impacts our sleep?

“Sleep is probably the single most effective thing that you can do to reset both your brain and your body.”@sleepdiplomat  

The Main Reason for Poor Sleep

Dr. Walker believes that we’re suffering from a global sleep-loss epidemic right now, and it starts with an image problem. 

“We associate sufficient sleep with this concept of being lazy or being slothful and that’s a terrible disservice to sleep. It is very different from things like diet and exercise. People [share] what they eat and [that they] work out five times a week, all of which are great and to be applauded and supported — but we have the very opposite [with sleep]. Some niches of society have this sleep attitude — ‘You can sleep when you’re dead’ mentality. We need to change our cultural appreciation of sleep from something that is a waste of time to something that in fact is an incredible investment.” – Dr. Matthew Walker

Sleep is probably the best and most freely available painless health insurance policy we have, and yet we work in a society that is working longer hours, even before the pandemic, with people commuting increasingly longer amounts of time. Longer commute times translate into leaving the house earlier and arriving home later — and no one wants to short-change time with family, or Netflix, or whatever your downtime is. Thus the one thing that has become squeezed in a vice is sleep. 

“Then there are plenty of people who give themselves the opportunity to get enough sleep, but they can’t obtain it. We know that one of the principal roadblocks to getting a good night of sleep is anxiety. Getting right with your emotions and your anxiety is key to good sleep. … At the public health level in many first-world nations, there have been wonderful government mandates for health regarding drink driving, drugs and alcohol, and even food — but when was the last time you heard of a first-world nation providing a public health message and memorandum regarding sleep?” – Dr. Matthew Walker

I think we can all relate to that, and we all know someone with an ethos that celebrates the airport warrior who’s flown through four different time zones in the past three days and was on email at two and then back in the office at six when they landed. Dr. Walker’s next data point shocked me. 

“After about 20 hours of being awake straight, you are as cognitively impaired as you would be if you were legally drunk. I would never as a CEO say, ‘I have this fantastic team of people that are drunk all of the time’, but we do say, ‘I’ve got this fantastic group of people dedicated [and] always working.’” – Dr. Matthew Walker

It’s not just with work — even the school system insists on early start times ranging from 06:30 onwards and the data is very powerful: It shows that when schools delay start times, first academic grades increase, then absenteeism rates decrease, psychological and psychiatric issues decrease, and what’s most alarming is that the life expectancy of students increased. That’s because the leading cause of death in teenagers 16 to 18 is actually not suicide — it’s road traffic accidents, which is where sleep matters enormously. 

“The following year, there was a 70% drop in vehicle accidents. To put that in context, the advent of Antilock Brake Systems (ABS) dropped accident rates by 20% to 25%, and was deemed a revolution. Here the simple fact of getting enough sleep will drop accident rates by 70%! What I would say is this: I think if our goal as educators is to educate and not risk lives in the process, then we are failing our children in the most spectacular manner with this incessant model of early school start times.” – Dr. Matthew Walker

It’s not just with the school system but in the corporate world too. The Rand Corporation did an independent survey and found that insufficient sleep will cost most nations about 2% of the GDP (their gross domestic product.) That’s a staggering amount when you quantify it looking at just three countries. In the US that equates to $411 billion of lost productivity due to insufficient sleep. Japan was $130 billion, and the UK was $50 billion — so by solving the sleep loss crisis within the workplace, we could almost double the budget for education in the US. 

Those stats affected my mood quite dramatically — which I just found out also affects sleep!

How Our Mood Before Bed Can Affect Sleep

Dr. Walker has spent some time working with people’s emotions before they go to bed. They already know emotional and mental health are intimately related to your sleep health and that the relationship is bi-directional. They wanted to see how much mood affected people’s sleep.

“If you manipulate people’s mood during the day, or particularly during the last hour before bed, mood and emotions will have an impact on your sleep. Conversely, how well you’ve slept will change how emotionally reactive and emotionally irrational you are the following day. If we do a negative mood induction before sleep, and we get people to focus on something that was really difficult in life, it has an [harmful] impact on sleep, whereas cultivating a positive mood before bedtime actually improves the quality of sleep what we call sleep efficiency.” – Dr. Matthew Walker

I doubt there will be any parents surprised by this study — how often have we heard a parent holding a child while they crying and the parent looks at you and says, “They just didn’t sleep well last night” as if there’s some universal parental knowledge that bad sleep the night before equals a moody and emotionally reactive child the next day?

Why You Should Listen to This Dr. Matthew Walker Podcast Episode Right Now…

Guys, this is such a powerful interview with Dr. Matthew Walker that I had to split it into two parts, and it is packed with so much value and many words of wisdom about sleep from him. Listen to the full episode for more, and don’t forget to share it with someone who needs to hear how to improve the quality of their health by learning about their sleep and how to improve it. I highly recommend you head over to part two here and check out Dr. Walker’s advice on the bad habits ruining your sleep. 

I like to end each episode with my guest’s definition of greatness, and you’ll be able to hear what Dr. Walker’s is in the next episode!

If you enjoyed this conversation, please make sure to spread the message of greatness and make an impact on someone’s life today. It would be great if you could also tag me, @lewishowes, and Dr. Walker, @drmattwalker on Instagram with a screenshot of this episode and your greatest takeaways from it.

I want to leave you with this quote from Jim Rohn who says, “Happiness is not by chance, but by choice.” 

It’s all about perspective. What we create and how we perceive the things that happen in our lives is how we develop gratitude around our experiences — and this shapes the way we view ourselves through the events that happen in our life. 

I want to remind you all — if no one has told you lately, you are loved, you are worthy, and you matter! I’m so grateful for you and do you know what time it is? It’s time to go out there and do something great.


To Greatness,


Lewis Howes - Signature

“Human beings are the only species that will deliberately deprive themselves of sleep for no apparent good reason.” @sleepdiplomat  

Some Questions I Ask:

  • How does sleeping poorly affect our brain?
  • How much sleep should we get?
  • How does a horrible diet affect your sleep when you’re getting enough sleep versus a good diet and poor sleep?
  • How do we influence our dreams?
  • Can we train our brain to lucid dream more?
  • What happens when we go into dream sleep?
  • Can people share dream experiences together?

In this episode, you will learn:

  • Why sleep is the foundational pillar for our overall health.
  • Why most people are terrible at prioritizing sleep and how to change that.
  • The effects of poor sleep over time. You NEED to know this!
  • How anxiety and stress affect our sleep.
  • The importance of dreams and how to influence them.
  • And much more…
Connect with
Dr. Matthew Walker

Transcript of this Episode

Music Credits:


Kaibu by Killercats

Comment below

let us know your thoughts

join thousands of
greatness subscribers
on your favorite platform