Dr. Walker is the Director of the Division of Nutrition (DON) at Harvard Medical School (HMS). He coordinates all activities of the DON and works closely with the Executive and Advisory Committees to implement new activities. Within the DON, he chairs the Subcommittee of Medical Student Education Nutrition and coordinates postgraduate educational activities in conjunction with the Department of Nutrition at the Harvard School of Public Health (HSPH) and the Clinical Nutrition Research Center at Harvard (HCNRC).
Dr. Walker, has a longstanding interest and commitment to nutrition research, particularly on the role of nutritional factors in maintaining the integrity of the intestinal mucosal barrier to host defense during the perinatal period. He was the first recipient of the Conrad Taff Professorship in Nutrition at Harvard Medical School in 1990. The research efforts of his laboratory have contributed substantially to a better understanding of the role of breast milk and its inherent growth factors on the development of the gastrointestinal tract and the role of short and long term malnutrition on the integrity of the mucosal barrier to host defense against bacterial colonization and against the uptake of macromolecules (antigens and toxins) which may result in neonatal and childhood intestinal disease states (necrotizing enterocolitis and gastrointestinal allergy).
Dr. Walker served for six years on the Committee of Nutrition of the American Academy of Pediatrics (1977-1983) and received the Nutrition Research Award (Borden Award) of the American Academy of Pediatrics in 1984 and the Hugh Butt Award for Excellence in Clinical Nutrition Research from the American Gastroenterologic Association in 1998. He has also served on Nutrition study sections at the NICHD and NIDDK institutes and the Advisory Council of NIDDK at NIH and recently served as a member of the task force to establish a five-year nutrition research plan at NICHD.
Dr. Walker is the author of 12 textbooks and over 500 research and review articles.