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?
Yeah, something like that, yeah.
Why? Well, I think the first thing is that we spend a third of our lives doing it and yet 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.
And 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.
Is it important? Is it important?
I think it is of fundamental importance.
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 of their brain at a time.
You know, animals like aquatic mammals or certain birds and dolphins that very much suggests, well, 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 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.
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 prioritised 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.
Having seen, you know, thousands and thousands and thousands of people that struggle with sleep that have been sent to your centre, do you think the average person on the street over or underestimates the importance of sleep in their day -to -day life?
Well, I think it's changing.
I think it was not that long ago where, you know, 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 sort of 15 or 20 years whereby people have become much more aware of how important sleep is and have started prioritising it a little bit.
So you think, where do you think we stand then, overestimate, underestimate?
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.
Yes, I think so. I think that there is a danger at the current time that we tend to obsessionalise about sleep and think that it is the be -all and end -all.
It's 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 overemphasise the importance of getting eight or eight and a half hours of sleep every night, then you actually risk problems later down the line, exacerbating things like insomnia.
The average person that you have treated, worked with, in your clinical practice that are struggling with sleep is, at the heart of the issue, just poor sort of sleep hygiene like you've said there.
Because I've got so many friends that say to me that they struggle with their sleep, many of them have struggled with it for years, and I doubt that there's some sort of genetic reason why this many people are struggling with sleep, so I imagine it's just some kind of behavioural reason.
So I think that the genes that predispose to insomnia are pretty widespread, but obviously you know, in pretty much all areas of medicine there is an interaction between genetics and environment, and certainly poor sleep hygiene, and that's a horrible term, I hate that term, but it's the term that is most
widely used and understood, can certainly put in place certain aspects of behaviour that then can give rise to chronic insomnia in the long term.
So if you've got very bad chronic insomnia, then suddenly putting good sleep hygiene in place is unlikely to fix it, but it may be that that poor sleep hygiene in the first instance gave rise or at least predisposed you to developing insomnia.
And what is poor sleep hygiene?
If I wanted to be the worst possible sleeper in the world, what would I have to do?
So I think you would probably have to set up your home office in your bedroom, you'd have to have your TV on in your bedroom all the time, be surrounded by electronic devices, drink a lot of coffee late in the evening, drinks a little bit of alcohol, so alcohol in the short term of course is quite sedating,
it's a central nervous system depressant, but it does dramatically worsen the quality of your sleep and for various reasons, the direct chemical effect, the fact that you've got a full bladder, the fact that you're probably snoring a little bit more so alcohol's not a good thing, you know, not having
a wind down period, so you know, gambling on the stock market until 1am switching your laptop and then trying to go to bed, those kinds of things.
So that's the quintessential very, very bad sleep hygiene.
What about when I eat?
So eating is perhaps less important, but avoiding a very large carbohydrate meal, carbohydrate rich meal before you go to bed for two reasons.
One is that we know that it can cause some fluctuations in terms of your blood sugar and also if you've got a bit of reflux it can make that much worse.
Okay, what about sleeping in bed with somebody else?
Well I think that for some people, and again this goes back to no one rule for everybody, you know, if you've got a sleep trait termed sleep reactivity which is where your sleep is very liable to your environment, then obviously sleeping next to somebody who's snoring loudly or who gets up in the middle
of the night two or three times to urinate can be very disruptive to your sleep.
If you've got very little sleep reactivity you may actually find it comfortable, more comfortable to sleep with somebody in the same bed as you.
I was thinking the other day because it where I've currently moved into, there's no blinds or curtains in my bedroom, and I was wondering if that might be a good thing because it at least means that in terms of my circadian rhythm I'm waking up at the same time every day because I'm waking up when the sun
comes up. Yeah, but the sun comes up at different times on different days firstly, so if you were doing that routinely you might find yourself really rather sleep deprived in the summer months and also there is some emerging evidence that exposure to light at night in your sleep is not very good for you.
There was a very recent study that implied that light exposure at night increases your risk of diabetes.
It certainly is not good for the quality of your sleep and the likelihood is that you won't wake up as soon as it's light, you'll wake up at an hour or so after it's got light, but during that hour or so it may have had a negative impact on the quality of your sleep.
Having a dark bedroom is really part of good sleep hygiene as it's having a quiet bedroom that is not too hot or too cold.
What if you wear a sleep mask?
Does that solve it?
Yes, it does. I wear a sleep mask, I think it's particularly if you don't have good blackout curtains or blinds in your bedroom using a sleep mask particularly in the summer months is probably very helpful indeed.
Does that mean that the only light receptors we have are behind our eyes?
Well, I think that there were some rumours on the internet that there were light receptors elsewhere but certainly the only ones that we know to be of significance in terms of defining our circadian rhythm are the ones in our retinas.
