Why We Sleep: Unlocking the Power of Sleep and Dreams

“Why We Sleep is an important and fascinating book…Walker taught me a lot about this basic activity that every person on Earth needs. I suspect his book will do the same for you.” — Bill Gates

NEW YORK TIMES BESTSELLER & INTERNATIONAL SENSATION — This “stimulating and important book” (Financial Times) dives deep into the purpose and power of sleep.

Renowned neuroscientist and sleep expert Matthew Walker reveals the critical role of sleep in every aspect of our health and functioning. Once a mystery, the science of sleep now shows how it affects learning, memory, emotions, immunity, metabolism, and creativity.

Within the brain, sleep strengthens learning and decision-making, balances emotions, restores the immune system, and regulates appetite and metabolism. Dreaming blends memory and imagination, fueling creativity and insight.

Drawing on groundbreaking research and decades of clinical experience, Walker explores how sleep influences longevity, hormone balance, mood, and disease prevention—including cancer, Alzheimer’s, and diabetes.

He also offers practical, science-backed strategies to achieve better sleep every night and improve your overall well-being.

Clear, engaging, and transformative, Why We Sleep is “compelling and utterly convincing” (The Sunday Times) and “recommended for night-table reading in the most pragmatic sense” (The New York Times Book Review).