David S. Ludwig, MD, PhD, is an endocrinologist and researcher at Boston Children’s Hospital, Professor of Pediatrics at Harvard Medical School, and Professor of Nutrition at Harvard School of Public Health. Dr. Ludwig’s research explores how diet affects metabolism, body weight and risk for chronic disease – with a special focus on low-glycemic index, low-carbohydrate, and ketogenic diets. Described as an “obesity warrior” by Time Magazine, Dr. Ludwig has fought for fundamental policy changes to improve the food environment. He has authored over 200 scientific articles and 3 books for the public, including the #1 New York Times bestseller Always Hungry?