Sleep has been a big mystery for long, as it has been unclear what purpose it serves, and why natural selection did not weed it out. After all, in earlier times, the period of sleep must have been one of considerable danger for humans (and even now for many animals and birds). And yet, sleep is a common requirement across the animal kingdom as well. In fact, birds and some sea creatures have the remarkable ability to sleep half a brain at a time.
Matthew Walker is a sleep scientist and does an exceptional job in this book of explaining what sleep achieves for us. In fact, sleep deprivation is extremely dangerous and there is not enough awareness of this. Modern lifestyle has dealt a blow to both our duration and quality of sleep, and the effects are already quite apparent.
While sleep has not completely revealed all its mysteries to us, a lot is now known after painstaking research over several years. Our sleep shuffles between NREM, Light and REM sleep – and all of them have their purpose. NREM sleep fortifies our memory helping in longer term recall, while REM sleep & dreams lend emotional balance and help us get to the big picture. The book discusses a large number of experiments detailing what happens when we skip sleep. Depending on the sleep cycle and the quantum of deprivation, the ill effects are nothing short of disastrous – lower immunity, failing memory, loss of emotional balance, pre-disposition to serious diseases such as diabetes, dementia and even cancer. Getting adequate sleep (~8 hours) on the other hand makes people more creative & productive other than being healthy.
Somehow, our cultures today do not emphasise the importance of sleep, as much as we do exercise and diet. So much so, that sleeping less is mistakenly regarded as a confirmation of working hard and being more ambitious. The assumption that each of us can do with varying periods of sleep is largely a myth as well. While a genetic mutation allows a few to function effectively with around 6 hours of sleep, this is extremely rare. Almost all of us do need ~8 hours of sleep. There are tips on improving sleep quantity as well as quality all through the book, such as regulating caffeine in the later part of the day.
Most of us are guilty of not according sleep the importance it deserves, and this book is an eye opener. This is a book everyone should read. There are very important points of note for individuals, educational institutions, hospitals, organisations and even governments.
Amazing book. Read it, skip a few chapters and see how much we are killing ourselves over sleeping less. I changed my ukg going son's schedule after reading this book and I have never seen him being so active and healthy and eating food willingly. Read it along with 'The Circadian Code' by Dr. Sachin Pandta and one can change a lot of things going wrong in terms of health and weight!!