Lipid requirements of infants: implications for nutrient composition of fortified complementary foods.

Dietary lipids have traditionally been considered as solely part of the exchangeable energy supply. The main consideration in infant nutrition has been the amount of fat that can be tolerated and digested by infants and young children. The significance of the composition of dietary fat has received little attention. Presently, there is a growing interest in the quality of dietary lipid supply in early childhood as a major determinant of growth, infant development and long-term health. Thus, the selection of dietary lipids during the first years of life is now considered to be critically important for health and good nutrition throughout the life course. Over the past decades interest has focused on the role of essential lipids in central nervous system development and of fatty acids and cholesterol in lipoprotein metabolism throughout life. Lipids are structural components of all tissues and are indispensable for cell and plasma membrane synthesis. The brain, retina and other neural tissues are particularly rich in long-chain PUFA. Some (n-6) and (n-3) fatty acids are precursors for eicosanoid formation; these are powerful mediators of numerous cell and tissue functions. Recommendations for infant nutrition and implications of these for the nutrient composition of complementary foods are presented and discussed. There is more to fat than its role as a key fuel in energy metabolism and body energy storage; lipids are essential for tissue growth, cardiovascular health, brain development and function throughout the life course.