Top Moment: The Real Reason You're Always Tired: Professor Guy Leschziner

Steven Bartlett (0:03)

Why sleep? Of all the things that you could commit so much of your time to, because it appears you've been really thinking and working on the subject matter of sleep for about sort of 20-odd years, two decades, roughly?

Guy Leschziner (0:12)

Yeah, something like that, yeah.

Steven Bartlett (0:14)

Why?

Guy Leschziner (0:15)

Well, I think the first thing is, is that we spend a third of our lives doing it, and yet we, whatever people like me will tell you, we still understand relatively little about it. We understand relatively little about what it's for, what it does to our biology. Obviously, that's changing very, very quickly now.

It has a great deal of overlap with the world of clinical neurology. So I also do specialist clinics in epilepsy, and I do specialist clinics in general neurology. Sleep and the brain intersect every single level. Of course, it's not me saying this, but a famous statement is sleep is of the brain, by the brain and for the brain. It's intimately linked to every aspect of how our brain works. So one of the really exciting things is that because it's a relatively new area, our understanding of it is exploding in ways that are not paralleled across other areas of clinical medicine.

Steven Bartlett (1:22)

Is it important?

Guy Leschziner (1:24)

Is it important?

Steven Bartlett (1:25)

Yeah.

Guy Leschziner (1:26)

I think it is of fundamental importance. You know, the fact is that if sleep wasn't important, it would be a very stupid thing for evolution to create in us. The fact that we are essentially switched off from our external environment for a third of our lives. And actually, there's a whole host of evidence when you look at how certain animals have developed the ability to be able to sleep with only half their brain at a time. You know, animals like aquatic mammals or certain birds.

Steven Bartlett (1:55)

Dolphins.

Guy Leschziner (1:56)

And dolphins, that very much suggests, well, you know, that must be of great importance if sleep is a risk for our survival, because if you're an aquatic mammal like a dolphin, and you're sleeping and you're unable to surface or unable to see what predators are around you, that the evolution has designed a system whereby it enables you to sleep with half of your brain at a time. So that in and of itself tells us it's important. That the fact that the circadian rhythm, so that 24-hour cycle that a whole host of biological rhythms have is so intrinsically linked to life itself, that actually every single life form exhibits features of this 24-hour circadian rhythm, tells us that this was something that was prioritized at a very, very early stage in life's evolution on earth. So yes, it's important. And over the last few years, we've understood precisely why it's important. I say precisely, but we know that it's important for pretty much every aspect of our waking lives, be it our immune system, be it our cardiovascular system, our blood pressure, risk of diabetes, mental health, so depression and anxiety, even how we perceive pain. So it really is fundamental to every system that we rely on during our waking lives.

Steven Bartlett (3:26)

Having seen thousands and thousands and thousands of people that struggle with sleep that have been sent to your center, do you think the average person on the street over or underestimates the importance of sleep in their day-to-day life?

Guy Leschziner (3:41)

Well, I think it's changing. I think it was not that long ago where comments like, sleep is for wimps was heard fairly frequently and that there were some bragging rights associated with how little you sleep. I think that there has been a transformation over the last 15 or 20 years, whereby people have become much more aware of how important sleep is and have started prioritizing it a little bit.

Steven Bartlett (4:06)

So where do you think we stand then? Overestimate, underestimate?

Guy Leschziner (4:09)

I think that there is still in the general population an underestimation of how important sleep is, but I think there are certain segments of the population that are much more aware of it and perhaps even dare I say overestimate it.

Steven Bartlett (4:24)

Overestimate it.

Guy Leschziner (4:25)

Yes, I think so. I think that there is a danger at the current time that we tend to obsessionalize about sleep and think that it is the be all and end all is of course part of normal life for our sleep to fluctuate depending on what's going on in our external and our internal lives. And I think the danger is that if you overemphasize the importance of getting eight or eight and a half hours sleep every night, then you actually risk problems later down the line, exacerbating things like insomnia.