Dr. Matthew Walker

And the depth, the size of those brainwaves and how dense they are, the number of them that you're having is another great measure of the quality, the electrophysiological quality of your sleep versus the, are you waking up lots throughout the night and therefore you're spending a lot of time awake, that sleep efficiency, that's another measure of quality.

And the depth, the size of those brainwaves and how dense they are, the number of them that you're having is another great measure of the quality, the electrophysiological quality of your sleep versus the, are you waking up lots throughout the night and therefore you're spending a lot of time awake, that sleep efficiency, that's another measure of quality.

So they're sort of orthogonal, but both bleed into this kind of second silo of sleep quality. So QQ, next one is regularity, going to bed at the same time, waking up at the same time. And you think this sounds fairly rudimentary and basic. Part of the reason is because you have a 24 hour master clock in your brain. And that clock thrives under conditions of regularity.

So they're sort of orthogonal, but both bleed into this kind of second silo of sleep quality. So QQ, next one is regularity, going to bed at the same time, waking up at the same time. And you think this sounds fairly rudimentary and basic. Part of the reason is because you have a 24 hour master clock in your brain. And that clock thrives under conditions of regularity.

So they're sort of orthogonal, but both bleed into this kind of second silo of sleep quality. So QQ, next one is regularity, going to bed at the same time, waking up at the same time. And you think this sounds fairly rudimentary and basic. Part of the reason is because you have a 24 hour master clock in your brain. And that clock thrives under conditions of regularity.

And when you feed it signals of regularity, like going to bed and waking up at the same time, it improves both the quantity and the quality of your sleep. That's what I used to preach as why it was important. until there was a great study published probably two and a half years ago. And it was, I think, over 300,000 individuals that they tracked with sleep assessments over a good period of time.

And when you feed it signals of regularity, like going to bed and waking up at the same time, it improves both the quantity and the quality of your sleep. That's what I used to preach as why it was important. until there was a great study published probably two and a half years ago. And it was, I think, over 300,000 individuals that they tracked with sleep assessments over a good period of time.

And when you feed it signals of regularity, like going to bed and waking up at the same time, it improves both the quantity and the quality of your sleep. That's what I used to preach as why it was important. until there was a great study published probably two and a half years ago. And it was, I think, over 300,000 individuals that they tracked with sleep assessments over a good period of time.

And then they looked at them across a much longer lifespan period of time. And they looked at mortality risk. And they also looked at different forms of mortality risk, cancer mortality risk, cardiovascular disease mortality risk. And they measured sleep quantity.

And then they looked at them across a much longer lifespan period of time. And they looked at mortality risk. And they also looked at different forms of mortality risk, cancer mortality risk, cardiovascular disease mortality risk. And they measured sleep quantity.

And then they looked at them across a much longer lifespan period of time. And they looked at mortality risk. And they also looked at different forms of mortality risk, cancer mortality risk, cardiovascular disease mortality risk. And they measured sleep quantity.

Sure enough, just like we've seen in many other studies, using that sweet spot of seven to nine hours, the shorter your sleep, the shorter your life. Short sleep predicted all-cause mortality. That's the quantity measure. They looked at regularity. regularity demonstrated the same thing.

Sure enough, just like we've seen in many other studies, using that sweet spot of seven to nine hours, the shorter your sleep, the shorter your life. Short sleep predicted all-cause mortality. That's the quantity measure. They looked at regularity. regularity demonstrated the same thing.

Sure enough, just like we've seen in many other studies, using that sweet spot of seven to nine hours, the shorter your sleep, the shorter your life. Short sleep predicted all-cause mortality. That's the quantity measure. They looked at regularity. regularity demonstrated the same thing.

Those who were in the lowest quartile, those who were least regular, highly erratic, they had far higher rates of mortality relative to the people who were in the top quartile who were incredibly regular. How did that compare to the quantity in terms of predictive power? Genius. And that was the brilliance of the study that really made me double down on regularity.

Those who were in the lowest quartile, those who were least regular, highly erratic, they had far higher rates of mortality relative to the people who were in the top quartile who were incredibly regular. How did that compare to the quantity in terms of predictive power? Genius. And that was the brilliance of the study that really made me double down on regularity.

Those who were in the lowest quartile, those who were least regular, highly erratic, they had far higher rates of mortality relative to the people who were in the top quartile who were incredibly regular. How did that compare to the quantity in terms of predictive power? Genius. And that was the brilliance of the study that really made me double down on regularity.

Because then what they did, they said, well, if we've got these two measures, quantity and regularity, let's not look at them individually. Let's put them in the same statistical model and do a Coke Pepsi challenge between the two. And all of us in the sleep field, you know, you're betting that quantity is going to be the more powerful statistical variable. It wasn't.

Because then what they did, they said, well, if we've got these two measures, quantity and regularity, let's not look at them individually. Let's put them in the same statistical model and do a Coke Pepsi challenge between the two. And all of us in the sleep field, you know, you're betting that quantity is going to be the more powerful statistical variable. It wasn't.

Because then what they did, they said, well, if we've got these two measures, quantity and regularity, let's not look at them individually. Let's put them in the same statistical model and do a Coke Pepsi challenge between the two. And all of us in the sleep field, you know, you're betting that quantity is going to be the more powerful statistical variable. It wasn't.