This program, directed by Dr. Ardythe Morrow, has two major goals: 1) characterization of bioactive factors in human milk and their health effects in breastfed children and 2) understanding factors that promote or impede breastfeeding. This unique research program is supported by a number of grants and contracts, including a longstanding NICHD-sponsored program project grant (PPG, HD 13021), “The Role of Human Milk in Infant Nutrition and Health,“ which was submitted for competitive renewal this year. This is only one of two program project grants in the U.S. focused on human milk or lactation, and the only one focused on child health outcomes. The PPG team (including, Drs. X. Jiang, K. Schibler, J. Meinzen-Derr, P. Huang, T. Farkas, M. Tan) has discovered that the oligosaccharides (molecules containing 3-32 sugars) of human milk have powerful anti-infective, prebiotic, and anti-inflammatory effects. The human milk oligosaccharides are a novel class of antimicrobial agents, and research is focused on identifying high risk populations for whom these agents provide protection against infectious and inflammatory diseases. We have found that oligosaccharide expression, measured using salivary or genomic markers, identifies premature neonates at high risk of death and necrotizing enterocolitis, and aim to test the hypothesis that human milk oligosaccharide given to premature infants helps protect against these outcomes. Other human milk bioactive factors that are being studied include major cytokines - adiponectin (Drs. J. Woo and L. Martin) and TGF-beta (Drs. M. Wills-Karp, L. Zuo, and A. Assa’ad) – in relation to immune system development and protection against inflammatory diseases. This program is further committed to research and education in breastfeeding: Dr. Woo has reported that in adolescents, a breastfeeding history is associated with protection against obesity, underscoring the importance of breastfeeding for lifelong health. Also, Dr. Geraghty has found that most breastfeeding mothers use pumps to maintain their milk supply, and that greater support of these mothers is needed. The human milk research program is a multi-disciplinary, multi-divisional effort and is planning to expand the depth of its work in collaboration with Neonatology and other divisions.