What are the age wise requirements of lipids?
Answers
Answer:
Explanation:
Lipids have traditionally been considered a part of the dietary energy supply. The total amount of fat that could be tolerated and digested by infants and young children has been the main preoccupation whereas the composition of dietary fat has received little attention. Interest in the quality of dietary lipid supply in early childhood as a major determinant of growth, infant development and long-term health is presently growing. Thus, the selection of dietary lipids during the first years of life is now considered to be of critical importance (1–4). Fats enhance the taste and acceptability of foods, and lipid components largely determine the texture, flavor and aroma of foods. In addition they slow gastric emptying and intestinal motility, affecting satiety. Dietary lipids provide essential fatty acids (EFA)2 and facilitate the absorption of lipid-soluble vitamins (4,5). Lipids are the main energy source in the infant diet, thus necessary for normal growth and physical activity. Lipids provide around half (45–55%) of the energy in human milk, and a similar proportion is found in most artificial infant formulas. They constitute the major energy stores in the body; the energy content of adipose tissue on a wet weight basis is seven- to eightfold higher than that of tissue containing glycogen or protein because the latter substrates are in a hydrated state.
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 the life cycle. Lipids are also 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 (LCPUFA). Some LCPUFA derived from the (n−6) and (n−3) EFA are precursors for eicosanoid production (prostaglandins, prostacyclins, thromboxanes and leukotrienes). These autocrine and paracrine mediators are powerful regulators of numerous cell and tissue functions (e.g., thrombocyte aggregation, inflammatory reactions and leukocyte functions, vasoconstriction and vasodilatation, blood pressure, bronchial constriction and uterine contractility).
Dietary lipids affect cholesterol metabolism at an early age and may be associated with cardiovascular morbidity and mortality in later life. Lipid supply, particularly EFA and LCPUFA, have also been shown to affect neural development and function (6–10). Evidence indicates that specific fatty acids exert their effect by modifying the physical properties or membranes, including membrane-related transport systems, ion channels, enzymatic activity, receptor function and various signal transduction pathways. More recently the role of specific fatty acids in determining levels of gene expression for key transcription factors, peroxisome proliferator-activated receptors (PPAR) and retinoic acid receptors has renewed the interest in better defining the role of these critical nutrients in the regulation of lipid metabolism, energy partitioning, insulin sensitivity, adipocyte development and neural function across the lifespan (6–10).