Book excerpt: Ori Hofmekler, acclaimed author of The Warrior Diet and one of the first proponents of intermittent fasting, challenges conventional wisdom about diet, fitness, and anti-aging with a new approach to health that uses stress to live longer, stay fit, and ward off fat. Supported by cutting-edge research, this book redefines the term "nutrition" as it reveals the stress-mimicking nutrients that yield the same benefits as fasting and exercising. At the core of the book is the biology of stress and the way it affects key aspects of life from feeding and sexual behavior to mental and physical performance. Hofmekler demonstrates that that there is a thin line between beneficial stress and harmful stress, and shows how to put knowledge of the difference into powerful practice. His book is a call to action--a manifesto of living life to its utmost evolutionary potential, under stress, as nature intended.