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Why We Sleep

The New Science of Sleep and Dreams

This book can be downloaded and read in Apple Books on your Mac or iOS device.


'Astonishing ... an amazing book ... absolutely chocker full of things that we need to know' Chris Evans

'Matthew Walker is probably one of the most influential people on the planet' Evening Standard


Sleep is one of the most important aspects of our life, health and longevity and yet it is increasingly neglected in twenty-first-century society, with devastating consequences: every major disease in the developed world - Alzheimer's, cancer, obesity, diabetes - has very strong causal links to deficient sleep.

In this book, the first of its kind written by a scientific expert, Professor Matthew Walker explores twenty years of cutting-edge research to solve the mystery of why sleep matters. Looking at creatures from across the animal kingdom as well as major human studies, Why We Sleep delves into everything from what really happens during REM sleep to how caffeine and alcohol affect sleep and why our sleep patterns change across a lifetime, transforming our appreciation of the extraordinary phenomenon that safeguards our existence.

'Startling, vital ... a life-raft' Guardian

'A top sleep scientist argues that sleep is more important for our health than diet or exercise' The Times

'Passionate, urgent . . . it had a powerful effect on me' Observer

What's New in Version 1.1.1

1.0.1 Minor revisions to the text

Customer Reviews

This is the best book I have ever read!

THANKYOU Matthew for writing this truly illuminating, witty book - it is a must read!. As a medical student I should know better but unfortunatley since starting university my sleep has declined to an measly 6 hours average and my concentration, focus and memory have all gravely suffered as a result - this book has completely changed the way I view sleep and from now on I will be absolutely prioritising my sleep - NO EXCUSES! This should be taught in all medical schools as it absolutely has the ability to change the health of nations.

Such an insightful book

Since reading this, I have been on a personal mission to improve my sleep, and have been preaching to friends, family and colleagues about the benefits of good sleep.

The information presented in this book is overwhelmingly persuasive and I’m sure any sensible person who reads and thinks about the content for themselves will definitely reassess their attitude to sleep for the better.

Why we sleep

An extremely thorough and simplistic illuminating practical study of such a fundamental basic human function yet so simple to apply! John Coxon

Why We Sleep
View in iTunes
  • £4.99
  • Available on iPhone, iPad, iPod touch, and Mac.
  • Category: Psychology
  • Published: 28 September 2017
  • Publisher: Penguin Books Ltd
  • Print Length: 368 Pages
  • Language: English
  • Version: 1.1.1
  • Requirements: This book can only be viewed on an iOS device with Apple Books on iOS 12 or later, iBooks 1.5 or later and iOS 4.3.3 or later or a Mac with iBooks 1.0 or later and OS X 10.9 or later.

Customer Ratings