"Signals is a special book, ... [an] utterly fascinating guide to who you are and how you work. It's compassionate, humane and grounded in the author's deep clinical experience. A true gift." Chris van Tulleken, author of Ultra-Processed People

In the tradition of Atul Gawande and Henry Marsh, a physician writer's expert examination of the extraordinary power of hormones and the miraculous story of the life force signals that make us.

Hormones write life's masterplan - building a new human being in utero, transforming a helpless newborn into a sturdy toddler, igniting the firestorm of puberty, conjuring the alchemy of fertilization and directing the transition into menopause and beyond.

And all the while, day-to-day, minute-by-minute, hormones control our mood and stress levels, how hungry we feel and how much we weigh, changes in libido and blood sugar, the circadian rhythm of our energy balance and sleep-wake cycle.

In Signals, Dr. Saira Hameed takes us on a journey through the endocrine system, the body's miraculous and often misunderstood communication network of endocrine glands and hormone signals. We barely notice these internal signals efficiently carrying messages from cell to cell because the power of hormones over our brains and bodies is so fundamental that their omnipotent control is simply felt as life itself. Yet when the body's signaling system breaks, we see with hindsight that be 'hormonal' is in fact to be human.

Here Dr. Hameed combines expert experience, revelatory science, medical history, and cultural commentary with compelling compassionately recounted patient cases. In this special confluence of storytelling Dr. Hameed invites readers to share in the mysterious, magical inner world of the endocrine system, going beyond hormone hacks and hype to tune out the noise and instead listen into the signals - to the powerful endocrine life force of how the body talks to itself.

• Category Defining Book: Hormones are in the zeitgeist and Signals provides answers about what they can and can't control.
• Understand Your Own Body: Expert-authored analysis based in science that leaves readers with a greater appreciation for how the endocrine system works and affects our lives.
• Gripping Medical Cases: Real stories of Dr. Hameed's puzzling medical cases that provide a peek behind the curtain as to how doctors work.