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Book Review: The Secret Life of Sleep

Kat Duff’s carefully researched, engagingly written, and wide-ranging The Secret Life of Sleep is an ode to sleep. The author documents the contemporary preoccupation with productivity, alertness, and cheating sleep. She points to the many ways we are urged along on that path, from breezy sloganeering (e.g., “you snooze, you lose”) to the popularity and easy availability of stimulants. But she’s not cheering for that mindset.

Instead, she enlightens us about the ways in which contemporary Western ways of sleeping and thinking about sleep are out-of-step with the ways people have been sleeping for centuries, and the ways they have been, and still are, thinking about sleeping and dreaming beyond the Western world.

Drawing from the latest research, Duff addresses all the questions you would expect in a book on sleep. They include, for example, how much sleep we need and how much we get, how it matters when we don’t get enough sleep, and what’s important about the different kinds of sleep we get and the different kinds of dreams we remember.

But then, instead of adding to our alarm about our sleep deficits and the effects of our sleep deprivation on our functioning, health, and well-being, she soothes us with reasons to relax. For example, she reassures us that we shouldn’t worry so much about not sleeping through the night. Throughout most of history, people rarely did and rarely expected to.

Yes, she concedes, it is true that people who are woken from a sound sleep — as happens often in sleep studies — don’t think as quickly, remember as well, or do math as successfully as those who got to sleep through the night. But why, she asks, do we measure and value such a narrow set of qualities? Instead, she asks, “Why not test for mental flexibility, emotional receptivity or creativity, qualities that emerge at the soft edges and lapses of waking focus?”

And why are we so obsessed with alertness and focus, to the exclusion of pensiveness and dreaminess? Duff goes on to say, “While there are some professions that truly demand long hours of sharp focus, such as surgery, most of us do not risk anyone’s life when our attention drifts. We can allow ourselves to cycle between phases of rest and activity, diffuse and pointed awareness, as our biology requires.”

More fundamentally, why do we cherish our waking hours so much more than our time spent sleeping? Why do we try to draw such a sharp distinction between the two, when in fact, the states are not so separate, and “our waking and sleeping lives require and inform each other?”

Duff doesn’t deny the serious implications of getting insufficient sleep or of sleep experiences that are disturbing rather than replenishing. But she thinks our contemporary perspectives on sleeping put too much of the onus for change on the individual rather than broader social forces: “Even though the causes of insomnia are usually located in larger socioeconomic contexts, be it the hectic pace of modern living, the prevalence of shift work, or new-fangled technology, the solutions offered are inevitably individual. Experts address the sleepers, rather than their employers or the city light department, with their lists of things to do and not do.”

There is a famous dictum in journalism and politics: Follow the money. That’s how you figure out who is ultimately benefiting. Duff follows the money of the sleep industry. She finds, for example, that in 2005, “more than twenty-six million prescriptions for Ambien were written in the United States alone, totaling more than $2 billion.” Yet on the average, sleep medications “increase the total sleep time by only 11.4 minutes. Moreover, functioning does not improve the next day.”

The big picture is even more telling: “Prescription and over-the-counter medications, sleep studies, white noise machines, earplugs, eye masks, apnea devices, sleep monitors, specialty mattresses, high-thread-count sheets, aromatherapy pillows, high-end beds, and alarm clocks fuel a sleep economy worth more than $20 billion a year.”

Over the course of The Secret Life of Sleep, Duff nudges us to be more open-minded in how we think about sleep and dreaming. In a section on dream visitations and travels, for example, she notes, “The notion that each of us has an immaterial soul, a shadow or secret self, which separates from the body in sleep, is ubiquitous among non-Westernized people.” I confess to being far too entrenched in my Western ways to take spirit travel seriously, but The Secret Life of Sleep was still a mind-expanding experience for me.

The Secret Life of Sleep

Atria Books/Beyond Words, March 2014

Hardcover, 256 pages


Book Review: The Secret Life of Sleep

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Bella DePaulo

Bella DePaulo is the author of How We Live Now: Redefining Home and Family in the 21st Century and Singled Out. Before she started studying single life, she published many articles on the psychology of lying and detecting lies.

APA Reference
DePaulo, B. (2016). Book Review: The Secret Life of Sleep. Psych Central. Retrieved on November 23, 2020, from
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Last updated: 25 Aug 2016
Last reviewed: By a member of our scientific advisory board on 25 Aug 2016
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