Weaning recommendations: the scientific basis.

Current weaning recommendations are based on nutritional need, physiologic maturation, and the behavioral and developmental aspects of infant feeding. Inadequate energy and protein intake and deficiencies of iron, zinc, vitamin A, and vitamin D are the most commonly observed nutrient deficiencies during infancy and weaning recommendations have focused on their prevention. This article reviews the data and summarizes implications for infant weaning in both developed and developing countries. Current published recommendations for infant feeding are outlined and major concerns are highlighted.