If like me you’re a chronic insomniac, or if you’re the parent of a young child or a carer or a shift worker, you may initially be put off by the tone of Why We Sleep. The author’s premise is that we are, as a society and as individuals, joyfully squandering our sleep time with terrible consequences – which he outlines, at length.

Like most people, there may have been a brief period in my teens and twenties when I wilfully deprived myself of sleep through a combination of alcohol and late nights, but I have spent many more years desperately trying to sleep through the night and feeling like a ghost in my own life as I struggle through the day. Still, I gave the book a chance and there is some interesting stuff in here.

The health benefits of sleep for physical and mental health are so great that he suggests, not entirely frivolously, that the question should be not why do we sleep, but why do we wake up? We need NREM (non-rapid eye movement) sleep to file away everything we’ve learnt during the day, to process it and move it from short-term to long-term memory. This is why cramming the night before an exam won’t work, because it’s sleep that allows you to properly integrate and retain what you’ve learnt.

I found what he said about REM sleep (where we dream) most interesting. This is where we make odd connections, have creative thoughts, gain a fresh perspective. Anyone involved in any kind of artistic project will know that feeling. You hit what seems like an insoluble problem, you go to bed and wake up the next morning with a solution that is not just feasible but feels inevitable. This applies as much in daily life – we talk about ‘sleeping on’ a decision all the time.

He’s a big fan of siestas (as am I) and talks about the genesis of the term ‘power nap’ which came from research on the optimum time for airline pilots to rest. It was found that a short sleep at the beginning of a long period of sleep deprivation (eg during a long-haul flight) was the most effective. The FAA decided to institute this as policy but rejected the suggested terms ‘prophylactic napping’ or ‘planned napping’ (the second was considered too managerial, the first, well you can guess). The trouble with the term ‘power napping’ is that it is now colloquially used to suggest a macho alternative to sleep, rather than a short-term expedient when a full-night’s sleep isn’t possible.

The book covers the body clock and circadian rhythms and even sleep in other species. The author also shares exhaustive evidence on the dangers of sleep deprivation, both immediate – such as driving while tired – and long-term, through poor health outcomes.

My slight qualm about the book is that the author is so evangelical about his position. You are left thinking that all the world’s problems could be solved if only we all got a regular eight hours sleep. He cites lots of research backing up his case but a general reader has no context. It’s a bit like watching a courtroom drama and being totally convinced by the prosecution’s case but not getting to hear the defence.

If you do have problems sleeping you are likely to be so frightened by this book that it will keep you awake at night. When was this golden age when everybody got their eight hours? How can we make the comparison? Maybe in past centuries people spent more time in bed (what he calls sleep opportunity) but unless you were wealthy you probably shared a room with several family members (and possibly other fauna). How much quality sleep would you have got in a room where a baby was teething or siblings were fighting or mice were scuttling?

The bit I was really excited about getting to was the chapter on insomnia treatments but all the author offered (after much fanfare) was the old cognitive-behavioural chestnut, which among other things insists on no napping (despite his earlier waxing lyrical on the benefits) and, more seriously, no reading in bed.

There’s a lot in Why We Sleep and overall I found it an interesting and informative read, albeit one without a miracle cure at the end of it.

Matthew Walker's book is full of new discoveries for me. Of course sleep is an important part of our life, but it's one that, unless we suffer from some kind of sleeping disorder, most of us tend to take for granted. Walker wants to emphasise the importance of sleeping 8 hours a day and he seems to have the scientific evidence to support it.

The book can be read by anyone as it doesn't use scientific jargon and I think it will change your life, or at least will challenge your perceptions about the significance of a good night's sleep.

I’ve suffered from insomnia for most of my life so this definitely interested me. There is a line in the introduction where the author says if you’re feeling tired when you’re reading this, please go sleep! I was reading this at about 3AM and thought.. yeah I’ll try to sleep. It’s incredibly interesting and the writing was accessible and easy to understand. Really good and thought provoking

A really interesting read. Quite detailed and scientific in places. Easy to skim and to jump in and out of chapters.

This book has enlighted me in so many different ways!
Matthew Walker is now my favourite scientist.

While non-fiction is not my go to, for pleasure, this was a delight to read. Walker made everything understandable, palatable and easy to relate to in modern day life. I gradually came to realise how important sleep was in my day-to-day life and how much I can do to help myself gain more enhance and better quality sleep.

The section on lucid dreaming was a revelation!

Everyone should read this!

Such a interesting read and so different from my usual genre.
I found it fascinating and the pages flowed well.

A fascinating and knowledgeable look at why we sleep and why it's so necessary, despite being somewhat undervalued in health terms. Personally I would have liked some more detailed science and I felt some of the conclusions might be slightly swayed by confirmation bias. That said this definitely provides food for thought.

Fascinating book from an expert in the field. Sleep is so important to ensure that we are able to face the many trials and tribulations of life; this book has made me realise that a) I don’t get enough and b) I’m not functioning as effectively as I could be because of it.
Not an easy read before bed, at least a couple of nights I actually lay awake worrying about my lack of sleep...

It took me so long to get to this book (which I also requested late, it didn’t help), and I’m wondering why! Although it *was* definitely scary, it was really interesting—and anyway, the ‘scare’ makes a lot of sense, so I wouldn’t be inclined as to consider it ‘alarmist stuff I can probably safely ignore because all these doctors and scientists write alarming stuff anyway’. I’ve had trouble to sleep for decades—while not a full night own, I’m clearly not a lark either, and this is part of my problems—and let’s be honest, it doesn’t take a genius to realise that on periods when I sleep less than 6-7 hours/night, I feel sluggiosh, fall sick more easily, stay sick longer, and am less focused in general. Considering my natural chronic lack-of-attention-span disorder, you can guess what it looks like.

(And now I’m wondering how much of this attention problem was really related to my Tourette’s, and how much was actually due to not sleeping enough... considering that when tics are flaring while in bed, well, falling asleep becomes an issue, too!)

Mostly what the author mentioned makes sense to me from a layman standpoint. Not enough sleep leads to increased risks of car crashes, due to microsleep attacks: yes, definitely, I almost went through that, and when I had to assess the risk of falling asleep at the wheel on a French motorway vs. stopping in a parking lot along that same motorway at 4 am to catch a couple of hours of shut-eye... Let me tell you, no argument about ‘it’s dangerous to be a female being alone at night in a deserted place’ would have made me keep driving. That was a scary, scary moment: feeling that I was falling asleep, and having those two or three seconds of complete inability to react, before I regained control of my body and managed to pull out. Yes, it was that bad. And I was extremely lucky that time. So I was definitely willing to consider Walker’s research in earnest, and not with my usual rolling-of-eyes at ‘alarmist books’.

Now, I also understand why my ageing parents are chronically tired, to the point of crashing on the sofa for a long nap every afternoon, yet can’t sleep most of the night. And why I’m going the same way, with the difference that for now I can’t afford to nap due to being at work. Naps reset the build-up of ‘sleep pressure’, and this affects in turn the moment when you’d get naturally tired in the evening, pushing it back by a few hours. (Also, now I get why melatonin pills don’t work for me: apparently I’m not old enough yet. XD)

In short, I finally got to understand a lot of things about sleep, which in turn will help me—I’m the kind of person who needs to ‘do’ and ‘understand’ in order to acquire and retain knowledge and act upon it, so this was actually perfect for me. Now I now what happens while we sleep, all the waste it helps our bodies get rid of, why sleep deprivation affects our emotions and moods, and many more things. It’s not a self-help book—while it does have an appendix with a few ‘tips and tricks’ about how to sleep better, don’t expect to see only that for two hundred pages or to find miracle cures—but it’s already doing a lot for me, just thinking about it. I can’t change my work hours, and society is not going to rearrange itself around me to give me more sleep time; but I can do little things like filtering out blue lights from my screens, not drinking so much caffeine (the old saying ‘coffee is OK as long as it’s before 5pm’ isn’t good enough, so slowly does one’s body processes caffeine), and stop begging my GP for sleeping pills.

Bonus point for the book’s accessibility. You don’t need to have medical knowledge or master its jargon to understand the author’s points. There’s even a bit of humour thrown now and then (that part about the women’s fashion magazine that was delighted to hear confirmed that ‘yes, sleep deprivation favours weight loss’... before the interviewed researcher went on to talk about the loss being mostly muscle mass and not fatty tissue, and let’s not forget the skin sores and generally awful look one develops).

Conclusion: If you do have sleeping troubles, read this, it should help with at least a few things. If you don’t, read it anyway, because it’s interesting.

This book gives the reader an interesting insight into the reasons why the body needs sleep . Matthew Walker discusses informatively the effects sleep and lack of sleep has on the human body and how this can it effect are every waking moment. If you're looking for a book on sleep this is a must read Walker has written it in a way that everyone can understand what he is talking about no science degree needed. Thank you Mr Walker

I really enjoyed this book. I'm not a big non-fiction reader, and some things went a bit over my head, but I learned a lot of things.

An interesting book which i found to be full of information, some things i knew already but as an insomniac i was really interested in learning more about the subject in the hope of improving the quality of my sleep. i found this book knowledgeable, and extremely helpful. Matthew Walker obviously knows his stuff and i really enjoyed his writing style, i found it a little hard at times but friendly all the same.
thank you to Netgalley, the author and publisher for allowing me to read in return for an honest review.

A fascinating look at how important sleep is for our mental and physical health, and how our modern way of life could be doing us more harm than good. A real eye-opener!

Matthew Walker obviously knows his subject very well and is passionate about it, however, the level of this book is more that of a text book than for the average reader. He does say he will find it a compliment if anyone falls asleep reading his book and I have to say it did induce sleepiness in me more than once!

Despite it being a little hard to wade through there are some gems of advice worth mentioning. Like you cannot combat tiredness when driving. All those tips you think you have he warns - forget them - you cannot beat sleep. So the message is do not drive if you are feeling sleepy.

I did find some of the findings repeated within the book from a very slightly different angle, to the academic it matters, to me a casual reader I got annoyed with the repetition. This isn't the first book I've read on sleep so a lot of the material I was aware of, apart from of course the authors own research.

The most interesting thing I learnt from this book is that there is a direct correlation between the rise of heart attacks and the commencement of daylight saving. There is also a reduction in heart attacks when daylight saving ends. Like a lot of very interesting statements in this book, especially regarding Alzheimers, I was disappointed that there is seemingly no follow through for them - they are just research findings.

I'm giving this book four out of 5 stars purely because it is a little heavy going, however, if you are reading this for your studies I think you would give it 5 stars.

Fascinating, easy to read, inciteful. I would encourage everyone to read this. Has certainly made me reconsider my sleep habits. I have recommended it to many customers.

Explanatory with humour, 'Why we sleep' is an informative read. Lots of information I didn't know and will put into practice. Took a bit of time to read as it's got scientific stuff in there, plus research. Recommended.

According to this wonderfully entertaining and thought-provoking exploration of sleep, it appears that all our ills can be alleviated, if not prevented altogether, by getting a good night’s sleep. Cancer, Alzheimer’s, ADHD, heart attacks, diabetes, even obesity – all will succumb to the power of 8 hours of uninterrupted slumber. Not only we as individuals will be better off, but so will the world, as bad decisions are usually made by those who are sleep-deprived – from doctors to generals to financiers. More road traffic accidents are caused by sleepiness than drink/drug driving. And how about this little known fact? Heart attacks peak on the day after the clocks go forward and slump the day after they go back and we all get an extra hour. Who’d have thought the solutions to so many of our sorry world’s problems can be found between the sheets.
OK, so I exaggerate a little, but in essence that does seem to be sleep scientist Matthew Walker’s argument, and I must say I found it pretty convincing. As parents we know instinctively that our crabby child is simply tired, that our teenagers really do need to sleep later in the morning, and that sleep is essential to well-being and recovery after illness (although we probably wouldn’t fall ill if we got enough sleep). This book attempts to explain the science behind sleep, and does so in an easy to read and accessible way. Some reviewers have taken issue with some of Walker’s conclusions, and maybe they are correct to do so, but so what, I ask? If simply getting more and better quality sleep can have even a small effect on our mental and physical health, then I for one am willing to take the lessons of this book to heart. So sshhh now please, I’m off to get my 8 hours…..

This is an interesting book based on an enormous amount of research. It was written in an accessible way, if a little repetitive at times. There were some scary stories of what might happen to us if we don't get enough sleep, but very few solutions for those of us who do not manage the requisite 8 hours per night for whatever reason. Maybe a follow-up is needed- "How to sleep better...." ?
There were tables and charts throughout the book which just came out as headings in my downloaded copy.

Why We Sleep was a really interesting, accessible read. Walker discusses what sleep is, why it is important, and how our understanding of it has grown. I found new facts surprising me every few pages, and I finished this book with a much better understanding of why I should get my eight hours every night. I hope more people read this, because Walker will open their eyes or oen of the most important aspects of mankind and society's wellbeing.

Trouble sleeping? Do you want a life-saving health regime with absolutely no side effects? If you answer yes to either (or both) of these questions this book is required reading. Although the book suffers a little from the author’s understandable desire to share as much background and supporting evidence as possible, which can mean the wood can sometimes be hidden by a close up of too many trees, the key messages he shares with his readers are potentially life-saving and, certainly, quality-of-life-enhancing. There is no category of reader who is not capable of applying the author’s advice and thereby enhancing her/his health; educational potential; or employment prospects. In addition to its relevance to everyday life, CEOs, managers and politicians should also consider the advice offered in the context of policy and HR development.