Dr. Dean Ornish is a pioneer in lifestyle medicine who is challenging and changing the status quo of how we treat disease — arguing we all have the power to transform our fate simply by the choices we make every single day. Dr. Ornish has been a driving force and inspiration to Dr. Oz since his early days in medical school. In this interview, Dean and his wife Anne join Dr. Oz to reveal how we can all press our inner “undo button” for better health with advice from their new book “Undo It: How Simple Lifestyle Changes Can Reverse Most Chronic Diseases.”