The Book

The Power of Two: A Twin Triumph Over Cystic Fibrosis
by Isabel Stenzel Byrnes & Anabel Stenzel
University of Missouri Press (2007; updated & expanded edition, 2014)

– Updated & Expanded Edition Available OCTOBER 14, Featuring a New Afterword by Ana and Isa! –

Born in 1972 in California to Japanese and German immigrant parents, Ana and Isa are identical twins who recount their lifelong struggle to pursue normal lives with cystic fibrosis while grappling with the realization that they will die young. This coming-of-age story reveals their tumultuous battle against their bodies, their desire for independent identities and their gradual acceptance of being loveable despite being physically different. In the end, the twins discover that their deep-seated dependence on each other has allowed them to survive long enough to reap the benefits of miraculous lung transplants. In the “Power of Two,” they share a life shaped by cultural tradition, dedication from a family that would not give up, and inspiration from others who have shared in the plight of having cystic fibrosis. This memoir is rich in life lessons, depth and appreciation.

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Book Reviews (first edition)

Three Stars; “the connectedness of twins shines” in this “grippingly honest” memoir”

–People Magazine (click here to read the full review)

“always powerful and filled with life and spirit, alike.”

–Frank Deford, Author, “Alex: The Life of a Child”

“This miraculous story of twin sisters who grew up with cystic fibrosis is gripping and uplifting. . . . This book is mandatory reading . . . . It is a story about the power of hope and determination.”

–Howard Dean M.D., former Governor of Vermont and Chairman, Democratic National Committee

“This account is a winner in every respect.”

–Bruce Reitz M.D., Cardiothoracic Surgeon, Norman E Shumway Professor, Stanford Medical Center


“This miraculous story of twin sisters who grew up with cystic fibrosis is gripping and uplifting. It is a chronicle of the triumph of modern medicine, both in terms of heroic surgery and the less glamorous, but ultimately more important tedium of daily chronic care. There are thousands upon thousands of Americans living with cystic fibrosis. This book is mandatory reading for them and their families. It is a story about the power of hope and determination.”- Howard Dean M.D., former Governor of Vermont and Chairman, Democratic National Committee

“Isabel and Anabel’s memoir of their extraordinary battle with cystic fibrosis is at once uplifting and frightening, touching and tough, but always powerful and filled with life and spirit, alike. It is a story that we all must be moved by, grateful that these two sisters shared their agony and love with us.” – Frank Deford, Author, “Alex: The Life of a Child”

“It is the unfortunate habit of books on illness and recovery to rely heavily on sanitized clichés. The downs are very down, the ups sky-high. This honest and carefully observed account avoids preconceived notions of the complicated path toward an organ transplant. Describing the stages of the affliction in detail, it makes you feel you were there, suffering a pain you had heard about but never really visualized, aware that death is no longer just a concept but could come at any time, and experiencing the complex emotions that come with being saved because someone else died. For readers who have not been close to a wasting disease, it will be an eye-opener, horrifying but in the end inspiring, a tale of courage being tested all day and every day.” – Reg Green, Author, “The Nicolas Effect: A Boy’s Gift to the World”

“This is an inspiring story of how two twins Isa and Ana are thriving with cystic fibrosis and double lung transplants. The story shares how CF can be an aggressive and cruel disease, but with resilience, good family and health care compliance, they were still able to lead very productive, active, social, and professional lives. A book of HOPE and a must-read for any parent of a CF child or a person living with CF.” – Boomer Esiason, NFL Pro Football Player, President, Boomer Esiason Foundation, Parent of CF Child

“Ana and Isa Stenzel were born against odds of 1.8 billion to one; identical twins of a Japanese mother and German father, with the crippling disease, cystic fibrosis. Continuing against even greater odds, they succeed in education and in living, and the long odds of listing for and receiving double lung transplants. These improbable events are in fact, true, and provide a fascinating and enlightening read. The beauty and the pain of the human condition continue to amaze us. This account is a winner in every respect.” – Bruce Reitz, MD, Cardiothoracic Surgeon, Norman E Shumway Professor, Stanford Medical Center

“This is a great book for professionals in healthcare, biology and biotech. I first met Ana and Isa when they were Stanford college students. They were two of the more than 900 cystic fibrosis patients who volunteered to participate in the clinical study that established the benefits of inhaled Pulmozyme. I have always taught doctors in training that our patients inspire us and that we learn so much when we really listen to them. Readers of this book will be inspired by their story. They will learn much about cystic fibrosis and about life. They will learn that it is not the number of days that we live that matters, it is what we do with every day that we are fortunate to have.” -Steven Shak, MD, PhD, Chief Medical Officer, Genomic Health, Inventor of Pulmozyme

“This is an excellent narrative that takes us through the twists and turns of high-tech medicine and transplantation. Written with insight and courage, this is a book to use with students of medical anthropology and those interested in culture and healing. ” -Elizabeth Strober, PhD., Medical Anthropologist, Lecturer, Seattle University

“Isabel and Anabel: twins with CF. Each author is unique, authentic. And each is a mirror to the other, offering the reader intimate insight into life with cystic fibrosis. These two women reveal their histories with candor and compassion. They help us find strength within ourselves and from our communities to rise above difficulty and breathe the freshness of each new day. Those with chronic illness will find a voice in this book for the daily challenges they themselves face and for the rich joys of life that others may take for granted. I read this book in one sitting – and now I revisit the pages to keep in touch with their compelling story.” – Carroll Jenkins, Executive Director, Cystic Fibrosis Research, Inc.

“One of the hardest and earliest lessons we learn is that life isn’t fair. Perhaps for that reason I don’t usually take to inspirational books, which often attempt to portray a particular example of misfortune as a special gift, to be appreciated for its character-building qualities, or failing that, for an advantage so mysterious that no mere mortal can discern what it might be. Fortunately, that genre is transcended by The Power of Two, an astonishing account by twin sisters born with a genetic disease that should have killed them in infancy, and almost did. But they survived that and numerous other close calls and are now in their 30’s, with degrees from Stanford University, newly transplanted lungs, and a gift for writing that takes us directly into their lives. This is an intimate, brutally honest and compelling memoir.” – Jeffrey Wine, PhD., Professor of Psychology, Pediatrics and Director, Program in Human Biology, Stanford University