The routines of our modern lives and its technology are playing havoc with our body clocks, sleep patterns, and health. Foster explains how we can get back into rhythm and live healthier, sharper lives. Sleep and daily rhythms emerge from our genetics, physiology, behavior, and the environment. These rhythms are modified by how we act, how we interact with the environment, and how we progress from birth to old age. Foster empower readers to understand how their own body clock "ticks."--Adapted from jacket.

"First published by Penguin Random House UK in the United Kingdom in 2022 as Life time: the new science of the body clock, and how it can revolutionize your sleep and health."--Title page verso.

Introduction -- The day within -- A heritage from our cave days -- The power of the eye -- Out of time -- Biological chaos -- Back in the rhythm -- The rhythm of life -- The seven ages of sleep -- Time out of mind -- When to take drugs -- A circadian arms race -- Eating time -- Finding your natural rhythm -- The circadian future -- Appendix I: Studying your own biological rhythms. Part I. Developing a sleep diary ; Part II. Chronotype questionnaire -- Appendix II: The key elements and overview of the immune system.