Hugely interesting insight written in a really accessible and well-researched readable style. I’m a little bit obsessed with sleep at the moment (and not getting enough of it!) Would recommend!

I can see why this book was rated so highly as there is loads of useful information in it. It is a heavy read so I had to be in the right frame of mind when reading it, however, I'm not sure how else the reader would have packed in so much useful information. The author goes into detail about sleep deprivation, the history of why med students and doctors are pressured to work long hours with little sleep and the usual info about the best methods for getting off to sleep. Some of the information is reminders for the reader such as impressing how important it is not to drive when sleepy and emphasizes the reasons why. Definitely recommend. #WhyWeSleep #NetGalley

A fascinating insight into sleep - what prevents it, the different sleep cycles and how you can help yourself. Wish I'd read it 20 years ago

Sleep has always been a subject that fascinates me and I was eager to learn more from this comprehensive study written by  Professor of Science, Matthew Walker. I have always wondered why we all need different amounts of sleep and why some people fall asleep easily, but for others, it can be a huge problem.

The book covers a myriad of subjects involving jet lag, the effects of caffeine and alcohol, dreaming, the use of sleeping pills... to name but a few. The overriding message was however, that lack of sleep can have horrific consequences by linking to Alzheimers, Cancer and Diabetes etc

I read the ebook version of the book but I will buy the paperback for easier reference. The information was fascinating to read but it would be easier with more subcategories. It's not the type of book to read in one sitting and I found it was repetitive in parts.

My other problem with the book was that from the perspective of an insomniac it was quite disturbing because it emphasises how important sleep is to our health and wellbeing. If insomnia is triggered by anxiety, I would be tempted to give this book a miss because it could make the problem worse. In fairness, there is plenty of advice to help insomniacs in the book.

I think this is a book that I will refer back to on a regular basis, in fact, it will be placed on my bedside table as a reminder of how important sleep is. I admired Professor Matthew's passion for this subject and wish him well getting the message across.

Thank you, NetGalley for a review copy which I have reviewed honestly.

Why We Sleep is an incredible book about the nature of sleep and how science can help us have better sleep. Having suffered from intermittent insomnia for two decades I have learnt tips and strategies that I will use in my day to day life. A book.everyone should read.

This book is taking me ages to read, I've been at it for months, so I'm going to note things down so I remember once I finish.

• So. Freaking. Interesting.
• I now know facts about sleep in various animals.
• Why can't I sleep?
• I am now fascinated watching people sleep and it's freaking my family out
• These tests... It's crazy what lack of sleep can do
• I want to know more about the health implications
• That's so sad :(
• Yeah OK I need sleep
• Must. Sleep.
• Everyone should sleep.

Popular science books usually fascinate me, but I was left feeling a little underwhelmed by this book.
Although it is obviously informative and accessible to the general public, my main gripe is that the author is a little too preachy for my liking. Although it's obviously beneficial to get a decent night's sleep (and the benefits are explained in a great amount of detail), it's not always possible, and the author does nothing to dispel that type of reader's fear. It would have been nice if it was a little more 'if you can't get 8 hours sleep, here's what you can do to help yourself...', rather than being so judgemental.
Technically, it's a great book but I really wouldn't advise reading it if you are worried about your sleep patterns...and I would guess a large proportion of the people who are interested in reading this book must fit in that category.

I have read several books and watched TV programmes on sleeping, but Why We Sleep: the New Science of Sleep and Dreams is one of the most in depth and thorough books on the subject that I’ve come across. It is fascinating and disturbing in equal measures.

It emphasises how important sleep is to our health. Eight hours sleep each night will improve your immune system, help prevent infection, regulate your appetite, lower blood pressure, maintain your heart in fine condition, improve your ability to learn, memorise and make logical decisions.

But be warned if you don’t get eight hours sleep you run the risk of doubling your risk of cancer, of increasing your risk of developing Alzheimer’s disease, diabetes, cardiovascular disease, strokes, and heart attacks, and insufficient sleep contributes to all major psychiatric conditions, including depression, anxiety and suicidal tendencies. It is a terrifying scenario as every major disease in the developed world has very strong causal links to deficient sleep.

Matthew Walker is professor of neuroscience and psychology at the University of California, Berkeley, where he is director of the Center for Human Sleep Science. He goes into great detail examining every aspect of the subject looking at what sleep is, how we sleep, as well as why we should sleep and the external factors that cause poor sleep. There are sections on sleep deprivation, sleeping pills, insomnia and other sleep disorders and on dreams – creativity and dream control. He also considers the sleep requirements of babies, children, teenagers and the elderly.

There are a number of things I highlighted as I read the book, including:

sleep is the foundation of good health
every major system, tissue and organ of your body suffers if your sleep is short
the shorter your sleep, the shorter your life
the less you sleep you’re more likely to put on weight
sleeping six hours or less increases your risk of developing cancer by 40%
routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer
He cites the World Health Organization’s and the National Sleep Foundation’s stipulation of an average of eight hours of sleep for adults. So, what can you do to improve your sleep if you don’t get eight hours? I really want to know. Walker refers to behavioural methods for improving sleep, such as cognitive behavioural therapy intended to break bad sleep habits, obvious methods such as reducing caffeine and alcohol intake, removing LED devices from the bedroom and having a cool bedroom. Other things to establish – having a regular bedtime, only going to bed when sleepy, avoid sleeping in the early/mid evenings and daytime napping etc, etc – nothing I haven’t come across before.

Why We Sleep is full of fascinating facts, but at times it is repetitive with lots of detail about sleep experiments that made me worried about the effects on those people who undertook them. Matthew Walker is most certainly on a mission to educate people about the importance of sleep, even if there is nothing new he has to offer about how to improve sleep times.

Many thanks to Penguin UK for a review copy via NetGalley.

As someone who suffers from insomnia, I was very interested to read 'Why we sleep' in order to try and make sense of why I do not.
In the U.K most adults suffer from a sleep deficit that just doesn't get better and it affects so much of our cognitive and reasoning functions yet gets little support in improving it.
The pace of modern life is such that switching off becomes ever more difficult and this book offers ways in which science is identifying triggers to sleeplessness as well as tools for improving how we sleep as well as how long.
It is a must read and also quite terrifying so for a midnight reader like myself who tells myself'just one more chapter..'I really need to sit down and have a stern conversation about my appalling habits. Thanks to Netgalley and the publishers for allowing me to read this in return for an honest review.

I received a free copy of this book from the publisher in exchange for an honest review.

Why We Sleep is, as is probably obvious from the title, about the scientific and health effects of sleep, an area which Walker points out is still bizarrely lacking from our understanding of health despite the fact we all spend a quarter to a third of our lives in this state. The initial chapters of the book tackle what we currently know about the process and functions of sleep, including what REM and non-REM sleep do for us. The middle of the book, perhaps more relevantly for most of us, deals with the effects of a lack of sleep, considering both the acute effects of the occasional missed night (reduced ability to form memory, weakened immune system) and the cumulative impact of chronic sleep deficiencies and the long-term mental and physical problems these cause, as well as the effects of alcohol, caffeine, sleeping pills and the simple process of ageing (all bad) to get the eight hours of sleep we all (with very few exceptions) need every single night.

It all builds up into a pretty grim picture for any of us with a lifestyle that involves stress, late nights, weekend lie-ins, caffeine, alcohol and/or the looming spectre of a family history of insomnia. Indeed, reading Walker’s interview last year was one of those rare instances where information on health caused an immediate shift in my behaviour: I stopped charging my phone in my bedroom, ditched my alarm clock in favour of waking up naturally (which turns out to happen between 6:30 and 7:30am, although I haven’t tested this in a Northern European winter yet…), and am now in bed by 10pm a much higher percentage of the time. The book has definitely reinforced my commitment to those habits, although to be honest the effect of most of the additional information has been to wince and shrug – I’m probably not going to give up my moderate caffeine or alcohol consumption even now I know it’s probably lost me more memories than just the obvious ones. Still, it’s good knowledge to have even if it’s not the advice we’d want to have.

Walker’s style is highly readable for the most part, although it is science-heavy and there were a few more data rich parts that were slightly dry. The occasionally rather dire health warnings are balanced out with cheesy professorial humour which might not be everyone’s cup of tea, but it’s not particularly overdone. There were also a few moments involving cross-cutting areas where I rolled my eyes at some of the biases within the text: for example, the segment on sleep and reproductive health fixated heavily on the relationship between sleep and low testosterone and how that would be the worst thing ever for men (Cordelia Fine might have a thing or two to say about that?) There’s also an early section on autism which describes autistic brain function as “inappropriate” and puts out a (hedged) hypothesis about the links between “deficient” REM sleep patterns and the cause of autism. I’m no expert on the science of autism, but I strongly suspect Walker is not either, and the casual way this was dropped in for a page apparently just to underscore how "autistic people do sleep wrong and that's why us normals need to get it right" really rubbed me up the wrong way.

Regardless, this is recommended reading for the subject matter alone, dealing as it does with an area of health most of us underrate and know very little about. That it’s packaged in a decently readable book form is an added bonus.

A brilliant read about the one topic I have always been curious about.

I wish I’d known about the power of sleep all my life. On the one hand, it’s obvious – if you have a good night’s sleep you tend to wake up feeling better – but on the other hand I simply hadn’t understood just how powerful and miraculous sleep is. Matthew Walker writes accessibly and explains clearly, illuminating the scientific discoveries and placing them in context very successfully. Since I read this book I’ve talked to everyone about the importance of sleep and I highly recommend Why We Sleep.

Absolutely fascinating book on sleep written by a sleep scientist. Presenting copious interesting research on why we do it and what happens when we sleep. All written in an easy to read interesting style.
Incredibly interesting and useful to learn of the things that can affect sleep quality and sleeping times, along with the quite astounding knock on effects that not getting sufficient sleep can have on our health. Loads of interesting anecdotes gained during the author’s research career too.
Sleep must be just about the best free health and beauty bonus we can get. A really good and useful read.
Many thanks to NetGalley and Penguin for a copy of this great read in exchange for an honest review.

Given my husband’s diagnosis of severe sleep apnea and the difference the treatment from the sleep clinic has made to all aspects of his life, when I saw this book was available on NetGalley, I immediately requested it.
Sleep is one of the most important but least understood aspects of our life, wellness, and longevity. Until very recently, science had no answer to the question of why we sleep, or what good it served, or why we suffer such devastating health consequences when we don't sleep. Compared to the other basic drives in life—eating, drinking, and reproducing—the purpose of sleep remained elusive. An explosion of scientific discoveries in the last twenty years has shed new light on this fundamental aspect of our lives. Now, preeminent neuroscientist and sleep expert Matthew Walker gives us a new understanding of the vital importance of sleep and dreaming. Within the brain, sleep enriches our ability to learn, memorize, and make logical decisions. It recalibrates our emotions, restocks our immune system, fine-tunes our metabolism, and regulates our appetite. Dreaming mollifies painful memories and creates a virtual reality space in which the brain melds past and present knowledge to inspire creativity.
Walker answers important questions about sleep: how do caffeine and alcohol affect sleep? What really happens during REM sleep? Why do our sleep patterns change across a lifetime? How do common sleep aids affect us and can they do long-term damage? Charting cutting-edge scientific breakthroughs, and synthesizing decades of research and clinical practice, Walker explains how we can harness sleep to improve learning, mood, and energy levels; regulate hormones; prevent cancer, Alzheimer’s, and diabetes; slow the effects of aging; increase longevity; enhance the education and lifespan of our children, and boost the efficiency, success, and productivity of our businesses. Clear-eyed, fascinating, and accessible, Why We Sleep is a crucial and illuminating book.
Normally I don’t include all the blurb, as it tends to give too much away. However, in this case I feel it nicely sums up exactly what this book is about. This was not a comfortable read. My husband’s snoring used to be epic – not only was it shredding his ability to sleep deeply, it also properly mucked up my sleep, too. It is still a mess and has been for a number of years. I have become accustomed to living reasonably happily on somewhere between four and five hours of sleep a night, and therefore it came as a very nasty shock to discover that I am probably compromising my immune system as well, as increasing my risk factor of incurring a range of nasty illnesses including Alzheimer’s and cancer.
However, the good news is that in addition to providing the scientific reasons why sleep is so important to us, Walker also provides a range of suggestions and tips so that those of us with really poor sleep hygiene have a chance to sort ourselves out. If you are a snorer, or sleep next one, find it difficult to get to sleep or stay asleep for the recommended eight to nine hours a night, then you need to read this book.
9/10

This isn't an easy book to read. It is full of data, experimental results and academic research BUT it is definitely worth persevering with. The biggest takeaway is that not getting enough sleep - at least 7 hours regularly every night - will shorten your life. Dr Walker takes his time to explain why and along the way we learn loads of fascinating stuff - who knew dolphins slept with each half of their brain separately because "One half of the brain must always stay awake to maintain life necessary movement in the aquatic environment." Or that elephants only sleep for four hours, while tigers and lions need fifteen hours. Brown bats sleep for nineteen hours a day!

The author explains how sleep is a delicate balancing act between meeting the demands of waking survival (hunting food, minimising energy expenditure and managing threat risks), serving the restorative physiological needs of an organism and tending to the more general requirements of the organism's community.

He talks about the effect of inadequate sleep - after sixteen hours of being awake the brain begins to fail - and sleep apnoea, driving accidents, illnesses and how to get your body and your bedroom ready for sleep.

This book could literally change your life. I was given a free copy by Netgalley in return for an honest review.

This is an engrossing account of sleep, what it is, why we need it, and what happens when we don’t get enough of the ‘right’ quality. It is wide ranging in that it also provides some fascinating facts about animals’ sleep patterns in addition to those of humans.

But the really important take-away from reading this is the dire effects on human health from the cumulative effects of long-term sleep deprivation, from; Type II Diabetes, heart disease strokes and Alzheimer’s Disease, to a variety of mental illnesses! In fact, most people in the ‘developed’ world appear not to get or be able to get the recommended eight hours a night. Parents with very young families live with and accept the reality of this; that’s why we have kids when we’re young enough to sustain the damage! But, like your annual ISA allowance, you can never recover the amount of lost sleep to top up your account again!

Not surprisingly then, considering the adverse effects on our mental health from lack of sleep, it also has a bearing on the effectiveness of any learning we are undertaking, whether formal or informal. The author, a long-term academic running a sleep research group, altered his own students’ assessment pattern so that they were not forced to give up sleep whilst cramming for exams. When he asked his colleagues in other departments to seriously consider doing the same, his pleas fell on deaf – and probably sleep deprived – ears!

The messages from this very well written, engaging and educative book should be essential reading for general practitioners together with the warnings against artificial (chemical) inducements for those who visit their doctor for advice on how to get more sleep. Everything in the book is supported by referenced research.

All in all, thoroughly recommended, but don’t stay up all night reading it!

This is definitely an interesting book. It really made me consider my own sleeping habits and patterns. Some of the things Walker describes were very recognisable, like that change in your circadian rhythm in your teenage years where you have no problems staying up till late, but it's agony getting up in the morning to be in school by 8AM.
I also liked the descriptions of all the research that has been done around sleep, it reminded me of my student years when I was a regular guinea pig for the psychology department.

However...
Walker is a bit of a doom-evangelist. If we don't get our 8 hours of sleep a day WE WILL DIE!! But not before we get Alzheimer's and diabetes and obesity and depression and low sperm count and lots of other nasty things. Look no further, sleep is the answer to all our problems. That's the general tone of the book, he uses the word 'catastrophe' regularly.

Another problem with the tone of the book is that it's not quite clear who the intended audience is. At times Walker explains fairly simple things like how to pronounce 'thalamus' or a common phrase such as 'prevention versus treatment'. But then he also uses words like 'aerobic output', 'terra firma', 'epidermis' where 'skin' would have been fine, or 'in perpetuam' for perpetually.

Then there were the not very funny jokes and abundant, annoying generalisations and assumptions about the general public.
Like:

-"You may have been expecting your general brainwave activity to be beautifully coherent and highly synchronous while awake,..."
No, that's not my expectation at all. Mostly because I don't contemplate my brainwave activity very often, but also because I would rather expect my brainwaves to be all over the place while awake, considering the hectic nature of everyday live.

-"Observe any post-lunch meeting around a boardroom table..."
Yes, I have dozed of during meetings, but not necessarily after lunch. Of course the after-dinner-dip is a known phenomenon, but to take it for fact that every after lunch meeting is by definition a snore fest???

So, overall, this book is worth reading. If you look past the cringy style and the endless descriptions of sleep experiments, you'll find a lot of interesting facts about sleep and enough food for thought about your own habits.

This book is packed with facts from years of research about sleep. It is a mixed blessing. It can leave you feeling worried about the impact of late nights but will also give you ammunition if you need to justify your need for sleep. I, for one, will have this ready if my employer ever tries to bring forward the start of the day again. On the other hand, I'm not sure if I am ever safe to drive on the roads!
I tried to read this book cover to cover but it is so dense with information that is frequently worrisome so it is probably best read by dipping into it as the author suggests.
As a society, we definitely do not value sleep enough and I hope this book helps the author achieve his mission to change this.

We all do it, some more than others, but it is vital to our well-being. Sleep is an essential part of our life and Matthew Walker, who is an expert on the subject explains why it is so important in easy to understand language. This book is full of interesting facts about sleep and the risks that we take when we don't get enough. And once you realise how important sleep is to enjoying a long and healthy life, don't think that this can be achieved by taking a pill just before going to bed. The reason is also covered in the book as well.
Thanks to Netgalley and the publisher for providing me with a copy of this book in exchange for an honest review.

We often hear that sleep, diet and exercise are the three pillars of health, but Walker, a professor of neuroscience at the University of California, Berkeley, goes further: he believes sleep is the platform on which diet and exercise rest. Getting 7–9 hours of sleep a night is not some luxury to aim for but an absolute essential for the brain to process new information and prepare for receiving more the next day. Dreaming is like overnight therapy, and fuels creativity. Sleep deprivation has been associated with dementia and cancer: it’s no accident that Margaret Thatcher and Ronald Reagan, who prided themselves on getting by on just five hours of sleep a night, both developed Alzheimer’s. Just a few nights of insufficient sleep can weaken the immune system and increase the risks of developing a serious illness. It’s no wonder Walker calls sleep loss an epidemic.

Here are some other facts I gleaned:

During primate evolution, the transition to sleeping on the ground instead of in trees meant we could sleep more deeply – not having to worry about falling out – and the resulting increase in REM sleep and dreams contributed to the development of complex culture and creativity.

Fetuses are asleep most of the time; they kick in their sleep. Alcohol use during pregnancy or breastfeeding can lead to a decline in the offspring’s sleep quality or quantity.

People with autism get 30–50% less REM sleep than neurotypical people.

The postprandial slump in energy many of us experience is evolutionarily inbuilt, and suggests that a short nap (30–40 minutes) would be natural and beneficial. For instance, some African tribespeople still regularly nap at the hottest point of the day.

Walker’s sleep tips are mostly common-sense stuff you will have heard before. His #1 piece of advice is to have a sleep schedule, always going to sleep and waking up at the same time. (“Catching up” on weekends doesn’t work, though napping before 3 p.m. can.) Set an alarm for bedtime so you’ll stick to it, he suggests.

It’s a fairly long and dense book, with smallish type and scientific figures, so I knew I was unlikely to read the whole thing, but enjoyed mining it for fascinating information about evolution, neuroscience and child development.