This volume establishes the scientific basis for addressing the many questions that surround the appropriate feeding of infants during their first year of life. Noting that adequate diet is more critical in early infancy than at any other time in life, the review considers what knowledge about infant physiology can contribute to the understanding of nutritional needs. More than 500 references to the literature are included. The evidence reviewed challenges several widely held assumptions concerning the need for proprietary formulas, the most appropriate time to introduce complementary foods, and the best feeding regimen for low-birth-weight infants. The book has six chapters. The first examines the physiological mechanisms that operate during pregnancy, affect fetal growth and govern the newborn's nutritional requirements. Chapter two provides a fascinating account of the physiology of human lactation. Health factors which may interfere with breast-feeding are discussed in the third chapter, which considers the case of infants with congenital and hereditary metabolic disorders, cleft lip and cleft palate, and different maternal illnesses, including infection with HIV. The fourth chapter, on complementary feeding, concludes that breast milk alone satisfies the energy requirements of the average infant for the first six months of life and that complementary feeding before that time can introduce a number of short- and long-term risks. The remaining chapters review the special needs of two particularly vulnerable groups: low-birth-weight infants and infants and young children during periods of acute infection.