In the messy world of nutritional science, some researchers rise above the others in their attempt to produce high quality and useful data. Dr. Ludwig exemplifies that role. As a practicing pediatric endocrinologist, he has seen first hand the rise in obesity, type 2 diabetes, fatty liver and other previously rare complications in adolescents. As a result, he has made it his mission to help us better understand the role of calories, the importance of quality of calories, and the importance of the quality of the science we read. Is a calorie just a calorie? Why are so many scientific studies not helpful in answering this question, and what can we do about that? Dr. Ludwig answers these questions and more.