Replaceable You

An Instant New York Times Bestseller A BEST BOOK OF 2025: TIME • SMITHSONIAN MAGAZINE • KiRKUS • CHICAGO PUBLIC LIBRARY A Goodreads Choice Awards Nominee From the New York Times best-selling author of Stiff and Fuzz, a rollicking exploration of the quest to re-create the impossible complexities of human anatomy. The body is the most complex machine in the world, and the only one for which you cannot get a replacement part from the manufacturer. For centuries, medicine has reached for what’s available—sculpting noses from brass, borrowing skin from frogs and hearts from pigs, crafting eye parts from jet canopies and breasts from petroleum by-products. Today we’re attempting to grow body parts from scratch using stem cells and 3D printers. How are we doing? Are we there yet? In Replaceable You, Mary Roach explores the remarkable advances and difficult questions prompted by the human body’s failings. When and how does a person decide they’d be better off with a prosthetic than their existing limb? Can a donated heart be made to beat forever? Can an intestine provide a workable substitute for a vagina? Roach dives in with her characteristic verve and infectious wit. Her travels take her to the OR at a legendary burn unit in Boston, a “superclean” xeno-pigsty in China, and a stem cell “hair nursery” in the San Diego tech hub. She talks with researchers and surgeons, amputees and ostomates, printers of kidneys and designers of wearable organs. She spends time in a working iron lung from the 1950s, stays up all night with recovery techs as they disassemble and reassemble a tissue donor, and travels across Mongolia with the cataract surgeons of Orbis International. Irrepressible and accessible, Replaceable You immerses readers in the wondrous, improbable, and surreal quest to build a new you.
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Is the bionic human just around the corner? 'Mary Roach offers a fascinating tour of the wonderful world of regenerative medicine.' TIME, The Most Anticipated Books of Fall 2025 Our bodies regenerate at a remarkable rate – our skin replaces itself every month, our blood every four. You can remove ninety per cent of a liver and it’ll still grow back to its original size (please do not try this at home). Others – the brain, the heart, the eyes – are more complicated. These stay with us for life. So what do we do when they break down? For centuries, medicine has searched for answers – sculpting noses from brass, borrowing skin from frogs and hearts from pigs and crafting eye parts from jet canopies. And as technology has grown ever more ingenious, so have our solutions. In Replaceable You, Mary Roach sets sail on the uncharted waters of regenerative medicine, exploring the remarkable advances and difficult questions prompted by the human body’s failings: When and how does a person decide they’d be better off with a prosthetic than their existing limb? Is there a sensitive way to harvest tissue and bones from the deceased? Which animals might be the best organ donors? Through experiments and interviews with patients, physicians, pathologists, engineers and scientists, Roach immerses readers in the wondrous, improbable and surreal quest to build a new you. 'Addictively readable... Don't miss it.' Deborah Blum, author of The Poisoner’s Handbook