ABSTRACT This K23 proposal describes a five-year research and training plan to facilitate Dr. Katherine Bell’s transition into an independent physician-scientist in the field of neonatal nutrition. Dr. Bell is a neonatologist with a strong foundation in patient-oriented research. Nutrient deficits occurring during the neonatal intensive care unit (NICU) hospitalization impair preterm infants’ growth and maturation during a critical period for development of the body and brain, adversely impacting long-term neurodevelopmental outcomes. The essential micronutrient zinc is crucial for infant growth and brain development, but the optimal zinc intake for preterm infants is unknown and current fortification strategies may be insufficient. Accurate assessment of nutritional status in preterm infants is facilitated by distinguishing lean mass—which reflects organ growth and maturation—from fat. The goal of this proposal is to determine the association between zinc intake in the NICU and lean mass accrual (as a marker of nutritional status) and to evaluate the clinical impact of variabilities in zinc intake on concurrent brain development and later neurodevelopmental outcomes. The hypothesis that greater zinc intake results in greater lean mass accrual, improved brain growth and maturation, and improved neurodevelopment will be tested through 3 specific aims: 1) Determine the association of zinc intake in the NICU with lean mass at term equivalent age. 2) Determine the association between zinc intake in the NICU and brain growth and maturation. 3) Determine the impact of neonatal zinc intake on neurodevelopmental outcomes at 2 years. This research is significant for the field of neonatal nutrition, as knowledge gained from this study will help determine optimal zinc intake for preterm infants and inform the design of nutritional strategies to ensure adequate micronutrient provision to all preterm infants. Dr. Bell’s mentoring team—Dr. Belfort (primary mentor) and Dr. Duggan (co-mentor)—provide complementary expertise in preterm infant nutrition and micronutrient requirements in children, respectively. Dr. Bell will also receive mentorship from distinguished scientists with expertise in key areas related to this work, including micronutrient biochemistry, breastmilk composition, neurodevelopmental assessment in childhood, and the developmental origins of disease. The training opportunities and resources at Brigham and Women’s Hospital, Tufts Friedman School of Nutrition Science, and Harvard Medical School are an ideal environment for the candidate’s career development. The candidate’s institution is strongly committed to her success. Dr. Bell’s detailed career development plan includes mentored research, didactic coursework including a formal degree in nutrition science, seminars, and presentations at scientific meetings. She presents a timeline for completion of the research aims and preparation of a future R01 application. The knowledge and training gain...