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1228 turns · 1 hr 51 minSleep is not an optional lifestyle luxury
Hmm
Sleep is a non-negotiable biological necessity. It is your elixir of life. If you're not getting sufficient sleep, let's say defined as either less than six hours of sleep, your immune system is one of the first things that we see is highly sensitive. There was a great study from UCLA, and they brought healthy individuals in, and they limited them to four hours of sleep for one single night. And then they looked to see what was the percent reduction in a set of critical anti-cancer fighting immune cells called natural killer cells.
Hmm.
And the next day there was a 70% drop, and that's one night of just four hours of sleep. Deep sleep is one of the most wonderful forms of natural blood pressure medication that you could ever wish for.
Hmm.
If I manipulate sleep and get you sleeping better, it has a measurable impact on your dementia mortality. There was a study where they took healthy, young, virile guys, and they put them on essentially a restricted amount of sleep, five hours of sleep for six nights. At the end of that one week, their level of testosterone was that of someone 10 years their senior. So I can age a man by a decade within just five nights of short sleep. It's never too late to start sleeping better. [dramatic music] My guest today is one of the most influential sleep scientists in the world. I don't think this guy needs much of an introduction. He's a professor of neuroscience and psychology, founder of the Center for Human Sleep Science, and the author of the international bestseller Why We Sleep. I loved filming this episode, and I hope you enjoy it. Without further ado, please welcome Dr. Matthew Walker.
Hey, Matt.
Chris, hello.
So good to see you, as per.
[laughs]
Um, hey, we are both British. That's a good start.
Unfortunately, huh? [laughs]
Yeah. Um-
For, for the people listening
And knowing the UK how I do 30 years ago, you know, sleep wasn't a sexy, trendy topic. In fact, people just weren't talking about it, right?
Yeah.
And so, you know, now it feels like this huge phenomenon. Certainly wasn't a topic that we were talking about, you know, 20-plus years ago when we were, not with any degree of granularity, when we were trying to optimize athletic performance. Like, we knew it was important, but not really how to optimize for it. This is a long-winded way of asking how and why did you end up studying the, at then, unsexy topic of sleep?
[laughs] Um, mostly because I'm a desperately unsexy, unsexy man.
[laughs]
Um, but I would say all of us in the sleep field, for the most part, we're all accidental sleep-
Hmm
... scientists. You know, no one, when you're five years old in the classroom and they say, "What would you like to be when you grow up?" No one's shooting their hand up and saying, "I would desperately love to be a sleep scientist," you know?
Right.
And so I was ... So I did medicine, um, back in the UK, then went into a PhD, and I was studying people with dementia, very early stage dementia, and I was using brainwave recordings with EEG slapped on the, uh, the scalp to see if I could differentially diagnose what type of dementia they had very early on in the course-
Hmm
... of the disease.
Episode notes
What if everything you're doing for your health — the diet, the exercise, the supplements — depends on something you may be overlooking every night?
Matthew Walker, PhD, neuroscientist, sleep expert, and professor of neuroscience and biomedical engineering at UT Dallas, founder of the Center for Human Sleep Science, and author of the New York Times bestseller Why We Sleep joins The LIVING Room Podcast to reveal why sleep is not the third pillar of health — it's the foundation on which everything else rests.
For decades, we've treated sleep as the thing we'll fix after we get our diet, exercise, and productivity in order. But what if that order is exactly backwards?
In this conversation, Dr. Walker explains why one night of 4 hours of sleep causes a 70% drop in cancer-fighting natural killer cells, how losing a single hour to daylight saving time spikes heart attack risk by 24%, and why dieting without enough sleep means up to 60% of the weight you lose comes from lean tissue — not fat. He unpacks the evolutionary paradox of why sleep exists at all, how dreaming acts as overnight emotional therapy by stripping stress chemistry from the brain, and why the single most powerful predictor of all-cause mortality isn't how long you sleep — it's how regular your wake time is.
In this episode you'll learn:
• Why one night of bad sleep causes a 70% drop in your immune system's