The Principles and Applications of Ozone Therapy – A Practical Guideline For Physicians is written by a practicing physician in the United States who has been using ozone therapy to treat patients or over 25 years. The book details how and why Dr. Shallenberger, an emergency room specialist, first became interested in ozone therapy. It then describes how his years of successful experience with it in a wide variety of medical conditions compelled him to discover how and why the therapy works so well. Ozone is a highly reactive form of oxygen. So he theorized that it works by enhancing the utilization of oxygen in the cells. In order to determine if he was on the right track, he developed a system which uses an FDA approved pulmonary gas analyzer to measure oxygen utilization. Then he began using that system in all of his patients. He discovered two unsuspected findings… First, many people, even those who feel great, are in a state of decreased oxygen utilization. They have plenty of oxygen in their bodies, but they are not using it efficiently. Second, ozone therapy tends to correct this condition. Based on these observations, Dr. Shallenberger then developed an entirely new paradigm for what causes disease and aging. He believes that the primary cause is decreased oxygen utilization. He presents biochemical and physiological evidence for this assertion.