Dr. Matthew Walker

Have you ever woken up after a full eight hours of sleep and still felt weary and tired?

I think this quote from the American inventor Joseph Cossman best sums it up, “The best bridge between despair and hope is a good night’s sleep.” 

What a treat it is then to continue my discussion with Dr. Matthew Walker in part two of our conversation about understanding the importance of sleep. Dr. Walker earned his degree in neuroscience from Nottingham University and his Ph.D. in neurophysiology from the Medical Research Council in London. Dr. Walker’s research examines the impact of sleep on human health and disease, and with that research, he’s written the international bestseller, Why We Sleep, unlocking the power of sleep and dreams. 

If you haven’t listened to part one already — I highly recommend heading over here to hear about the importance of prioritizing sleep. In part two today, we discuss how sleep affects your intimate relationships, why naps are good for you but can be bad for you if you do them wrong, how caffeine, smoking, and alcohol affects your sleep, and the simple hacks you can start doing today to improve your sleep. 

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, London, UK. He later became a Professor of Psychiatry at Harvard Medical School, USA. Currently, he is a Professor of Neuroscience and Psychology at the University of California, Berkeley, USA. 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!

Relationships and Sleep

Dr. Walker’s research shows that couples with a strong loving relationship will typically both have significantly better sleep, in terms of quantity and quality. What’s more astounding is what the data shows when both partners have poor sleep.

“If I take a healthy young man and put him on four hours of sleep for one week, they will have a level of testosterone of someone 10 years their senior. A lack of sleep will age a man by a decade [with regards to] wellness and virility. In women, we see a reduction in estrogen, luteinizing hormone, and follicle-stimulating hormone which are critical for female sexual health and reproductive health as well.” – Dr. Matthew Walker

When couples aren’t sleeping well there tends to be more conflict too, creating a vicious circle for poor sleep after more unresolved conflict. Part of the reason is losing empathy and becoming more self-centered and less compassionate toward the other due to poor sleep. This creates a bi-directional relationship regarding sleeping together in the same bed. 

“The data is very interesting. About 30% of people surveyed anonymously will report not sleeping in the same bed. Up to 40% of them will report waking up in a different location for whatever reason.” – Dr. Matthew Walker

Overall the data shows when people sleep together the quantity and the quality of their sleep is worse. However, most people will tell you they’re happy with their sleep and more satisfied by sleeping in the same bed. This is an important distinction Dr. Walker makes about thinking we sleep better together when in reality that might not be true. 

Sleeping in separate rooms — Dr. Walker uses the term “Sleep Divorce,”— seems to have a bad stigma, but he stresses the importance of couples giving themselves permission to explore and discuss this. There are many reasons sleeping separately is beneficial, from sleep disorders such as sleep apnea, snoring, tossing, and turning — all of which have the effect of creating friction in relationships leading to another bad night’s sleep. 

“It’s fine to tell people ‘I love you, I care for you, I don’t sleep well when we’re together. I think I would be a better partner if I could try to sleep in a separate location.’ The funny thing is, for the majority of nighttime, [we] are not aware of the partner. What we miss is the bookends of sleep. Saying good night, having a cuddle, and waking up in sync.” – Dr. Matthew Walker.

Dr. Walker provides a hack to this system. Whoever goes to bed first, can send a text saying they’re about to turn the lights off and ask, “Can you come through?” Then you can give them a kiss and a cuddle and have your bedtime moments. 

Conversely in the morning, whoever wakes up first can start making their tea or coffee and when the other person wakes up texts them, “I’m just waking up, come through” and you can go through to the bedroom and you can have your backend bedtime union. 

“It sounds like a lot of work, but the cost-benefit you get in terms of healthy sleep and how good you will feel and how much better the statistics tell us relationships are when couples have well slept, I think is worthwhile at least exploring.” – Dr. Matthew Walker

It’s certainly not a one-size-fits-all approach, but considering how important sleep is and how many things can negatively affect our sleep, Dr. Walker’s practical tools on how to have the conversation with our partners is a great way to create the best environment for quality sleep and a healthy relationship. 

Let’s take a look at what other factors within our control can help us create restorative sleep.

Caffeine and Alcohol

I’m curious to hear what Dr. Walker’s research shows about the effects caffeine and alcohol have on the quality of our sleep. 

“Coffee is associated with lots of health benefits [like] antioxidants. … Many people like to wake up and enjoy a coffee or two in the morning — [just] be mindful of whether you’re sensitive or not.” – Dr. Matthew Walker

If, like Dr. Walker, you’re one of those individuals who has a slow caffeine metabolizer, have one cup in the morning and preferably decaf after that, and this way your sleep won’t be negatively impacted by caffeine. The effects of caffeine on the body, even if you have a cup of coffee at midday, can be detrimental — a quarter of that caffeine consumed at midday can still be circulating in your system at midnight. If you want to wake up feeling refreshed by your sleep, limit the coffee you have after midday depending on your sensitivity unless it’s decaf. 

Alcohol has four consequences on the body, impairing us to enjoy a restful night’s sleep.

“The first is that when people [think], ‘It helps me fall asleep.’ Alcohol is in a class of drugs we call ‘sedatives,’ and sedation is not sleep.” – Dr. Matthew Walker

Sedation is where the brain cells are switched off — as opposed to deep sleep, which is when hundreds of thousands of brain cells coordinate in their firing, unlike any other time we see during the 24-hour period. 

“The second issue is — alcohol will fragment your sleep so you wake up many more times throughout the night.” – Dr. Matthew Walker

Dr. Walker wears the Oura Ring, which is a wearable tracking device monitoring how well you sleep at night. People wearing them explain that after a night of some drinking, their sleep is littered with awakenings, which is called sleep fragmentation. 

“The third problem is that it’s very good at suppressing your REM sleep or your dream sleep. During dream sleep is when the body releases the highest amounts of testosterone [in both men and women]. If you’re blocking your dream sleep, you [are not getting] that testosterone for recovery and restitution of muscle mass and muscle growth.” – Dr. Matthew Walker

The final problem with alcohol Dr. Walker has seen when people drink alcohol is a 50% decrease in production in the amount of growth hormone. The consequences that the data speaks to is people who drink tend to not live as long or tend to have worse quality sleep or age faster. The data shows that even one glass of wine at night will have an impact on sleep.