Long-term adequacy of exclusive breast-feeding: how scientific research has led to revised opinions

The present paper reviews the research of the authors and their colleagues over the past 20 years to provide improved nutritional and anthropometric g uidelines for the assessment of lactational adequacy and for when the weani ng process might be initiated. The nutritional guidelines are based on revi sed dietary energy requirements. The basic assumption is that since breast milk is a well-balanced food, if energy needs are satisfied so will those f or essential nutrients. Energy requirements for young babies have been deri ved from the application of the doubly-labelled water technique. This appro ach indicated that 460 kJ (110 kcal)/kg per d at 1 month and 397 and 355 kJ (95 and 85 kcal)/kg per d at 3 and 6 months respectively would be satisfac tory for a nutrient content of high bioavailability. Translated into a brea st-milk intake of 850 ml/d the latter would cover the dietary energy needs of the average child growing along the 50th centile until at least 4 months , but the typical child from many developing countries following the 25th c entile until 6 months. The importance of revised growth reference values fo r infancy, equally crucial for assessing lactational adequacy, is also revi ewed. In contrast with the shapes of earlier reference patterns, growth tra jectories are different when babies are fed in accordance with modern paedi atric advice. Mothers and health professionals using the older growth chart s to assess the progress of a baby can be misled into assuming that the wea ning process needs to be introduced sooner than necessary. Examples of this situation within the context of a developing country are provided.