Weight gain and obesity are driven by hormones and only by understanding the effects of insulin and its resistance we can achieve lasting weight loss. In the book, The Obesity Code, the author, Dr. Jason Fung, sets out an original, robust theory of obesity that provides insights into proper nutrition. In addition to the basic five steps, a set of lifelong habits that will improve your health and control your insulin levels, the author explains to the readers how to use intermittent fasting to break the cycle of insulin resistance and reach a healthy weight.