Samuel Klein is the William Danforth Professor of Medicine, Director of the Center for Human Nutrition, and Chief of the Division of Nutritional Science and Obesity Medicine at Washington University School of Medicine in St. Louis. Dr. Klein received an MD degree from Temple University Medical School and an MS Degree in Nutritional Biochemistry and Metabolism from MIT. He completed Internal Medicine residency training and a Clinical Nutrition fellowship at Boston University Hospital, a Nutrition and Metabolism Research fellowship at Harvard Medical School, and a Gastroenterology fellowship at The Mt. Sinai Medical Center in New York. He is board certified in Internal Medicine, Gastroenterology, and Nutrition. He was elected to the American Society for Clinical Investigation and American Association of Physicians. He has had consistent NIH R01 funding since 1990 and published more than 500 papers in nutrition, metabolism, and obesity. Dr. Klein’s research is focused on understanding the mechanisms responsible for the heterogeneity in metabolic function associated with obesity and the therapeutic effects of weight loss. He is committed to training young investigators and provided mentorship to 54 trainees in clinical translational metabolic research.