The Mystery of Sleep: Why a Good Night’s Rest Is Vital to a Better, Healthier Life

Kryger, a Yale Medical School professor and recognized sleep expert, seeks to educate readers about the effects of sleep disorders on daily (and nightly) lives. He stresses that “the one thing scientists are certain of” about sleep is that insufficient amounts interfere with people’s ability to think clearly and perform complex tasks. Part one of the book discusses physiological basics and sleep’s role at each stage of life, from infancy to old age, with specific chapters on how changing reproductive and growth hormone levels affect sleep. Part two is concerned with identifying sleep disorders, resetting the body clock, and coping with a world of constant distractions. Part three addresses insomnia and its probable causes at length, plus facts, signs, and symptoms of conditions that disrupt sleep: restless leg syndrome, sleep apnea, narcolepsy, medical and psychiatric conditions, and drugs prescribed for common health conditions. Part four, the most useful section, describes where to get help for common recurring problems, whether that means visiting a sleep clinic, beating insomnia with cognitive behavioral therapy, or taking sleep medication. Kryger’s self-help book ably marries science with a doctor’s advice, but reveals little that isn’t already available elsewhere. (Mar.)