Development of Structure and Function of the Gastrointestinal Tract: Relevance for Weaning

In different countries and societies there is a variety of successful weaning practices. This empirical observation leads immediately to the conclusion that there is a range of practices—qualitative, quantitative, and temporal—within which infants can thrive. In the elusive search for the "optimal" feeding regime, the changing nutritional requirements of the growing and developing infant must be matched to the maturation of functions and capacities of the gastrointestinal (GI) tract; however, it must also be remembered that within limits, some functional adaptation can occur. This chapter considers the question "Weaning: what and when?," and proposes some tentative answers from the viewpoint of a pediatric gastroenterologist, as follows.