A CONVERSATION WITH DR KATHARINA LEDERLE
ON YOUR MARKS … GET SET … SLEEP! OR NOT … AS THE CASE MAY BE!
We all know how tricky and elusive sleep can be. Even when we’re just about dead-on-our-feet with fatigue, sleep doesn’t necessarily romp up like a puppy when called. It won’t be rushed, urged, forced or rescheduled. And we all know what it’s like dragging ourselves through a long, tough day after a badly-broken night. (Never mind a string of ‘em!)
Sleep. It’s one of the few things that unites us. We all need it. We all do it. And oh-so-many of us wish we could do it better, right?
So, it was with real interest that we saw a new book come across the desk … ‘SLEEP SENSE’ by Dr Katharina Lederle, MSc, PhD. Katharina (‘Dr Kat’ as she’s known to her friends and clients) is an internationally famous sleep specialist (with a string of degrees and a CV to die for) who is de-coding this fast-evolving science for sleep-starved people the world over – and in terms we can understand.
What’s more, she has some practical, do-able suggestions to help us nod off – and stay nodded – till we’ve fully recharged the energy banks.
She sounded like someone we should talk to … so that’s just what we did.
GRAPEVINE: What exactly is sleep? And what’s happening in our brains and bodies when we’re asleep?
DOCTOR KAT: Well, we’ve a pretty good understanding now. It’s not yet perfect, but we do know that sleep is a shift in consciousness. When you look at someone asleep, nothing seems to be happening, but inside the body and the brain there’s lots going on … a lot of ‘repair-&-maintenance’ work.
Sleep’s important for our memory consolidation. It helps us to learn and process what we’ve experienced during the day from an emotional perspective. And then, physiologically, it’s important for all the organs and body systems to have a rest. When we’re active during the day, there’s wear-&-tear happening. At some point, the body has to repair this.
GV: What happens if we’re deprived of sleep?
DR KAT: If it’s over a long period, then the risk of illnesses goes up – diabetes for example, obesity, cardiovascular illness (the heart and its systems) to name just a few. Our immune system becomes affected as well, unbalancing our whole metabolism. If we don’t sleep it’s likely we’re active and eating at the wrong time of day, making sleep even more elusive. If we haven’t had enough sleep (we call that sleep debt) then concentrating becomes difficult. It’s harder, too, to make sense of the world. We’re less aware of what’s going on around us. We can even start to hallucinate. We also become more sensitive to pain.
And the longer we’re deprived, the worse the effects get.
GV: What got you so interested in sleep that you decided to specialise in it?
DR KAT: Well, doing biology and zoology, part of my Masters project was ‘seasonality’, which has to do with chrono-biology – the timing of things in the body. And it was when I did my PhD that I really got intrigued with sleep in its own right – it was just fascinating. I’d done so much thinking about chrono-biology and how our inner clocks affect our behaviour, it was natural to extend my studies into sleep.
The truth is, we all have something to say about this topic. We all sleep. Whether we’re good sleepers or poor ones – short sleepers or long sleepers – we all have opinions and experiences to talk about. Sleep as a topic interests everyone at least a bit, and many find it deeply fascinating.
GV: You say there are several different kinds of sleep – or different levels of sleep.
DR KAT: Broadly speaking, we have two main types of sleep. One is REM sleep, or “rapid-eye-movement” sleep. And then we have non-REM sleep (or NREM) and that is further subdivided into three levels: very light sleep, light sleep and deep sleep. We cycle through these stages each night over and over. And while REM sleep is commonly known as ‘dream sleep’, we do dream in the other sleep stages too. They’re just more … well, boring. If you think of REM sleep as dreams in colour, then the other sort of dreaming’s in black-and-white.
GV: How much sleep do we need and how do we know if we’re getting enough?
DR KAT: We have to pay attention to how we wake up in the morning. As the day goes on, how fresh do we feel? How easy is it to go about our daily work … or is it a struggle? There’s also something called ‘sleep inertia’, which is very normal. Meaning that when we first wake up, we may feel a bit groggy – it may take a bit of time for us to make sense of the world. For some people that’s five minutes. For others it can take an hour.
Another thing to note is we all have a dip in our alertness in the early afternoon. So, again, it’s quite natural that around lunch time we feel tired and dopey. But the main thing in assessing our sleep is that if we feel fresh and able to deal with things for most of the day – we’re fine. We’re getting enough sleep.
How much sleep we need varies. We’re all a bit different from each other. For a healthy adult between 18 and 64, the recommendation is between seven and nine hours. We don’t all need eight hours, but the majority of us need more than six.
There are some people who genetically only need maybe five hours or even less – but they represent just one percent of the population.
Many people cut their sleep short, and because we don’t really see the effects of this immediately, we sort of get used to living in a sub-optimal state. BUT … your body and your brain don’t get used to it. You’re building up a bigger and bigger sleep debt – and that’s trouble.
GV: Do you think that too many of us today, with work issues and family pressure, are not getting enough sleep?
DR KAT: Oh yes! And many of us ignore this and fill our lives with lots and lots of things that erode the time we make available for sleeping. Sometimes, of course, we just have to. I’m thinking here of a solo parent with a child or two who has to be available. She (or he) must wake up early to get them off to school … then work a full day … come home … make the dinner … do the chores … get everything ready for tomorrow … put them to bed … read the stories. And then, maybe, there’s a moment of down time – leisure time. You can’t blame her (or him) for wanting to read a book, watch television or relax a bit.
I do understand that decision. And this is where I think that we as a society need to provide some help for people affected like that. That ‘me’ time is absolutely important, but so is the sleep time!
GV: I suppose that in most cultures you find people who are owls and others who are fowls. (The owls go to bed late and wake up late, while fowls are the opposite.) Is that normal? Can we change from owl to fowl?
DR KAT: Basically, you go with what your body prefers. You can make some changes. But, importantly, we all have a built-in clock that sets the time when we naturally go to sleep and wake up. We can’t depart from it too far without trouble.
GV: Tell me about this clock.
DR KAT: The body clock is a group of cells (about 50,000) in your brain that sets the rhythm for everything that happens in your body … not just sleeping and waking. I like to compare it to an orchestral conductor. He tells each instrument when to play, and when to be quiet. Sometimes several instruments play together. Then they stop and someone else has a turn. It’s the built-in clock telling all of them when to play. But the conductor needs to be told when to start the concert!
GV: Teenagers seem to have a body clock that’s set much later than most adults’ clocks. They tend to stay up till very late – and then be almost unwakeable next morning. Is that true?
DR KAT: Absolutely true. In teenagers, the clock shifts to a later time. Some teenagers want to stay up really late … like 3.00 am … but they’ll still need about nine hours of sleep. So obviously there are going to be problems fitting them into the household routine. But when they get to about 19 or 20, the clock will shift back, so they’ll … well, let’s say, ‘normalise’ to some degree.
GV: Should schools be paying more attention to this?
DR KAT: Yes. And there is some awareness. Some schools are allowing for it. But, as you can imagine, it needs a massive shift in society. Who’s looking after the kids if they sleep late while mum and dad have to start work at 9.00? What happens in the evening? There’s all sorts of problems! But in terms of their grades and how they do at school, some shift would help … if we can manage it.
GV: This internal clock, I presume, is what makes us groggy when we travel internationally from one time-zone to another? What can we do to better adjust to local time?
DR KAT: It helps to understand the role of light. It’s sunlight that tells our inner clock that day has begun and we should be waking up. When it goes dark the message to the clock is: “Time for sleep!” Then the clock can tell the rest of the body what it should be doing.
When we arrive in the new time-zone we want to be awake when the locals are. So, before we leave, depending on which way we’re headed, east or west, we can pre-adjust our inner clock by exposing ourselves to light in the evening or no light in the evening. We can also try and take melatonin [a naturally-occurring hormone, available in tablet-form on prescription here in NZ]. Using light and melatonin, you can shift your body clock towards the time zone you’re going to need to adjust to … and you can do that a little bit even before you board the plane so when you arrive, jet lag won’t be so bad.
GV: Is it possible to sleep too long?
DR KAT: Yes, it is. Sometimes we build up that sleep debt when we sleep too little and then, as a result, we may sleep a bit longer. But a warning: our body clock craves regularity, so we should only do that sparingly. If we suddenly give ourselves too long a sleep, then our body clock can get confused. If our sleep’s just an hour longer than usual – and only once in a while – that’s okay.
But there’s more research coming out now that shows not only is sleeping too little detrimental to our health, it’s the same for sleeping too long … that is more than nine hours.
GV: I had a friend with very severe depression, and he would spend ages sleeping. Is disrupted sleep part of his mood disorder?
DR KAT: Potentially so. Sleep problems and mental disorders can overlap. So insomnia, for example, is a common symptom of anxiety disorders. Depression often means you sleep too little – but it can vary from person to person, and some oversleep. More research is going into that now, seeing whether we can detect a mental condition based on disrupted sleep. If we can stabilise that person’s sleep, there’s a good chance we can ease the depression or make it milder.
GV: How does having lots of stress affect sleep?
DR KAT: Well, put simply, what we do in the daytime affects our night-time … and how well we sleep at night affects our day. We call it the sleep/wake cycle. One follows the other – and they both impact on each other. Leading a stress-filled life (as I was suggesting in that example of the stressed single parent) will affect many areas of health. At bedtime, your thoughts are likely to be still tied up in all those tasks you’ve been so busy with. And they often keep racing around in your head, having a very bad effect on your sleep. Stress makes it more likely you’ll have problems falling asleep … problems staying asleep … problems waking up too early … problems all day feeling exhausted.
GV: So, what can we do to ensure the best chance of falling asleep quickly and easily without those chasing thoughts?
DR KAT: Well, preparing for sleep starts when you wake up in the morning. It’s not just a ‘bedtime’ thing. Make sure you get a chance to go outdoors soon after you wake up. Get some proper sunlight. This helps adjust the body clock in regulating your wake/sleep rhythm.
What we eat and drink is important … and when. Having a cup of coffee (or maybe two) in the morning is fine … but don’t have any caffeine after two o’clock in the afternoon. Have herbal tea or a non-caffeine drink.
GV: Sometimes, if I wake in the middle of the night and I’ve a busy day ahead, I can get quite stressed at not being able to get back to sleep … and the more I tell myself I must sleep, the less likely I am to actually get back to sleep. What’s the best thing to do here?
DR KAT: Let go of that pressure and tension – that anxiety and worry is working against you.
GV: But being told to “let the pressure go” is a bit like being told to relax when you’re in the dentist’s chair. How do we let it go?
DR KAT: Something I practice myself and teach my clients is mindfulness. That’s simply noticing what’s happening right now … experiencing things non-judgmentally. I just notice – but I don’t judge it. Whether it’s a positive or negative experience doesn’t matter – I notice it and I allow it to take place. If it’s night-time, I notice I’m awake – I notice that my mind is racing – I notice my heart is beating. Okay – I allow all this. Now, what else do I notice? Oh yes, I notice my pillow is behind my neck and my duvet’s touching me up to my nose. What’s my breath doing? What do I notice there? Oh yes, my breath is going in and out. I’m just lying here, calmly. So even if I don’t actually go to sleep, I’m staying calm and restful just lying here, comfortable and cosy, and making the most of the three hours or so before morning.
GV: So, doing that is better for you than chasing those wild thoughts and worrying?
DR KAT: Exactly. Resting has real benefits. If you lie there tossing and turning, anxious and caught up in the stress of worry, it’s likely cortisol is being released, and all of this reduces your energy reserves. This doesn’t mean I like lying there awake – but if I can lie there calmly, I’m saving my energy which I then have for the day. It’s not as good as sleeping for eight hours, but it’s much better than fighting and worrying for three or four hours.
GV: Do men and women need the same amount of sleep?
DR KAT: Again, this depends on the person. Generally, women do tend to go to bed earlier than men (or their inner clock tells them to go to bed earlier). Whether they need more sleep than men isn’t quite clear yet. But what is clear is that many women ignore their body clock to some degree, staying up later in order to have time with their partner, thus depriving themselves of some sleep. (They still have a definite time they must get up next morning.) And that leads to fragmented sleep. Their sleep is lighter and they’re much more likely to awaken during the night.
GV: Coming back to what you said about light telling us it’s morning and time to get going, tell us what’s been discovered about the colour of the light.
DR KAT: Light alerts us, tells our clock it’s daytime. But within the entire spectrum of light, we are most sensitive to blue light. We only need a little bit of blue light to trigger that ‘wake-up’ reaction.
Indoor light isn’t as bright and usually not as blue – so we can miss that ‘daytime’ message. But the real problem’s in the evening when we expose ourselves to our I.T. devices – the LED screens in our laptops, our phones, our tablets. With these, we’re continuously exposing ourselves to light – blue light, in fact, telling our clock “Daytime! Daytime! Daytime!”
GV: I often use my tablet to read books before I go to sleep and the screen seems to be white. Is it really blue?
DR KAT: LED screens emit a lot of blue light, whatever it may look like to us. If your device is an Apple it has something in it called ‘Nightshift’. You can activate this and filter out a lot of the blue. If you’ve an Android there’s lots of apps that do the same thing. ‘Flux’ is probably the most common one.
GV: But it’s still better to have a paper-and-ink book in your hand for your bedtime reading than a glowing LED screen?
DR KAT: Yes, much better.
GV: Another thing you mention is that if you’re a person who takes afternoon naps, it’s better not to sleep for more than 20 or 30 minutes. Why’s that?
DR KAT: We spoke about those stages of sleep earlier. We don’t want to get into deep sleep in the afternoon, because it’s much harder to wake up from. If we wake after just 20 or 30 minutes, we’re coming out of light sleep … so we’re more alert and we don’t risk confusing our body clock.
GV: And what is the role of dreaming in all of this?
DR KAT: Again, we’re not absolutely clear on this yet. (If you ask different specialists you’ll get different answers.) But it seems likely that dreams help us in processing our experiences and (again, very broadly speaking) it’s likely that what we do in the daytime is reflected in our dreams … processing experiences, memories, emotions.
Personally, I wouldn’t go crazy about dreams (trying to ‘interpret’ them). We can easily read too much into that, I think. But it’s interesting to pay attention to them. Do I dream? What do I dream about? Can I correlate it to stuff going on in my life? And if there does seem to be a connection, we can give ourselves time to deal with it and talk about it.
GV: There are things that can go wrong with sleep, aren’t there? Like insomnia?
DR KAT: Insomnia, specifically, is a problem of not being able to fall asleep easily, stay asleep, or of waking up too early. Some people have just one of these – for others, they cycle through all of them. But the big problem, of course, is that it affects our daytime … how alert we feel and how well we cope with our daily tasks.
GV: How do we know if there’s something wrong with our sleep – serious enough to require us to consult a doctor or sleep specialist?
DR KAT: It depends on what’s going on in your life. If you’re having a stressful period at work, a troubled relationship, someone has passed away – these can all affect our sleep. If something like this is affecting you, I’d suggest sticking it out for about two weeks. After that, if it’s continuing or getting worse, then perhaps you should see a doctor or sleep specialist, just to say, “This is what’s going on in my life. Is this normal? Can you help me?”
I’d say, though, that it’s better to see a specialist rather than browse the internet.
GV: What can we do to give ourselves the best chance of getting a good night’s sleep?
DR KAT: Most importantly, make sleep a priority. Good sleep, and enough of it, is essential for good health. We all need to acknowledge how important sleep is for ourselves and for the people around us too. Then, we do those things we’ve already talked about: minimise blue light exposure after dark … avoid too much caffeine … give yourself little ‘mini-breaks’ during the day. Do those and we’ve got a better chance of sleeping well and rising refreshed.
What we eatis important, too. I don’t mean that there’s some ‘superfood’ that’ll get us to sleep, but I mean we all need a healthy, balanced diet. And don’t eat too late in the evening, too close to bedtime.
Light, again, is important, so watch those LED screens and computers. Make sure they’re all finished with and turned off at least an hour before you go to bed.
And it’s not just the light itself, but what we’re reading or looking at. Is it too stimulating? These devices flash up all sorts of colourful, flickering images when we’re browsing that can side-track us and say, “Wake up! Look at this!” Avoid that!
Summing up, I’d say that sleep is a personal experience. The media often insist we need to sleep for eight hours between 11.00pm and 7.00am, and we need to get lots of deep sleep. But in fact we vary in how much sleep we need and when we need it. And when it comes to the levels of sleep, light sleep and REM sleep are just as important as deep sleep.
In my sleep window, when my clock says “now it’s sleep time”, if I make sure I do all I can to have my inner clock set right and I give myself the best chance to sleep when my body’s ready, then I get the most effective and refreshing sleep.
And what a difference it makes to feel alert and fresh all day!
‘SLEEP SENSE’ BY DR KATHARINA LEDERLE IS AVAILABLE IN NZ FROM is available in all good bookstores. FOR MORE INFORMATION ABOUT DR KAT’S WORK GO TO www.thesleepschool.org.