Clif Hostetler's Reviews > Why We Sleep: Unlocking the Power of Sleep and Dreams

The less you sleep the shorter your life span will be. Do I have your attention yet? If so read this excerpt from the beginning of this book (p3-5), and you will understand why this book caught my attention.

This book is divided into four parts. Part 1 defines the nature and types of sleep, describes how the need for sleep changes over a life span, and goes on to discuss the evolutionary origins of sleep. Part 2 describes why you should sleep and lays out the dire consequences of not sleeping. Part 3 explains how and why we dream, and Part 4 takes on the broader societal issues in dealing with sleep needs. An Appendix is included for "Twelve Tips for Healthy Sleep."

The primary message of this book is to emphasize the importance of adequate sleep. There are some suggestions included for obtaining adequate sleep, but the primary message is why it's important for health. An indication of how important is that lab mice that are deprived of sleep die sooner than those deprived of food.

The book ties the lack of sleep to numerous illnesses, and then proceeds to make the case that lack of sleep is either the cause or part of a negative feedback loop making the illness worse. By describing physiological and neurological interactions the author is able to show how lack of sleep is involved in these processes. Then population and diseases statistics are referenced to verify the involvement sleep or lack of sleep.

For many readers of this book the author will come across as an alarmist because he takes issue with so many things that we assume to be part of normal life. He makes a case that the early hours for beginning school makes no sense for optimum student performance. He sites one study that showed the average IQ of students in a school district was increased by starting school later. The author also makes a case for ending the practice of giving medical interns long work hours.

Some readers will not appreciate the negative things that the author has to say about caffeine and alcohol. Incidentally, if you think alcohol helps you to sleep you need to see what this book has to say about that.

The following are four things I learned from this book that I decided are worth highlighting here:

1. Sleep is the process by which the body removes waste products of metabolism from the brain. (This includes amyloid proteins which are associated with Alzheimer disease.)

2. People who are sleep deprived show reduced sensitivity to insulin. (This is a precursor for diabetes.)

3. Sleep deprived people experience hormonal changes that increases hunger and decreases satiation. (This leads of obesity and the resulting consequences including diabetes and heart disease.)

4. Sleep plays an important role in changing new memories into long term memories. (Sleep is better than studying all night.)

The following are excerpts and quotations taken from the book with my introductory remarks:

Are you a night owl or morning lark? Here's a link to an excerpt (p20-25) on that subject.

Here's a link to an excerpt (p68-61) about Biphasic sleep.

Lack of sleep is such a common experience for many of us that at first it's hard to believe the case being made by this book:

"...linking it [lack of sleep] to numerous neurological and psychiatric conditions (e.g. Alzheimer's disease, anxiety, depression, bipolar disorder, suicide, stroke, and chronic pain), and on every physiological system of the body, further contributing to countless disorders and disease (e.g., cancer, diabetes, heart attacks, infertility, weight gain, obesity, and immune deficiency). No facet of the human body is spared the crippling, noxious harm of sleep loss." (p133)

The book makes a convincing case that:

"We are … socially, organizationally, economically, physically, behaviorally, nutritionally, linguistically, cognitively, and emotionally dependent upon sleep." (p133)

I've included the following quotation since it applies to many today who live busy lives, including me somtimes. Researchers have evaluated performance of sleep impaired individuals and have found some sobering facts:

Most worrying from a societal perspective, were the individuals in the group who obtained six hours of sleep a night, something that may sound similar to many of you. Ten days of six hours of sleep per night was all it took to become as impaired in performance as going without sleep for twenty-four hours straight. (p136)

Here's another quotation that caught my eye:

There is no major psychiatric condition in which sleep is normal. This is true of depression, anxiety, post-traumatic stress disorder (PTSD), schizophrenia, and bipolar disorder. (p149)

Regarding cardiovascular health:

Adults forty-five years or older who sleep fewer than six hours a night are 200% more likely to have a heart attack or stroke during their lifetime, as compared with those sleeping seven to eight hours a night.(p165)

Concerned about cancer?

…the scientific evidence linking sleep disruption and cancer is so damning that the World Health Organization has officially designated nighttime shift work as a "probable carcinogen."(p186)

Lack of sleep can leave you more prone to Alzheimers disease. World Economic Forum, Jan.3, 2018

Sleeping Too Little in Middle Age May Increase Dementia Risk, Study Finds New York Times, April 20, 2021

The Mysterious Link Between COVID-19 and Sleep The Atlantic, December 21, 2020