Protein is an essential component of all human cells and tissues and the material basis of life, and the muscles, blood, membranes, skeletal bones, hair and teeth in the body contain a percentage of proteins。
Protein is a nitrogen-containing substance whose basic unit is amino acid. The importance of proteins for the growth and development of infants and young children is, in fact, the importance of amino acids, which are absorbed by the body by food proteins in digestive tracts, through the effects of protein enzymes in the stomach and pancreas。
Sufficient proteins are needed throughout the metabolic process of rapid growth and development of infant and child bodies. Protein also has the function of regulating the physiology. Infants and young children are in the process of growth of their bodies, with important effects on both the quality and quantity of the protein, which, if food protein supplies are irregular or the metabolism of the protein in the body is disturbed, pose serious developmental barriers, leading to illness and even death。
Nine essential amino acids are required for infants and young children during their growth and development, namely lysine, chlamydia, lysine, lysine, phenylamino acid, lactine, surasine, lysine, lysine and amino acid. These amino acids are not synthesized in the body and can only be supplied by food, and the amino acids of various food proteins can be filled in the body when mixed foods are consumed。
The demand for protein varies among infants and young children depending on how they are fed. In general, breastfed infants require proteins of 2. 0 to 2. 5 grams per kilogram per day and artificially fed children of about 3. 5 to 4. 0 grams (2. 5 to 3. 0 grams for young children). In the case of mixed feeding of infants and young children, animal protein is best not less than half of the total protein。
When protein intake is inadequate, the growth of infants and young children is stunted, body weight is reduced, muscles are reduced, immune capacity is reduced, anaemia and oedema occur, and even mental development is affected; if supplies are too high, they become condensed and hungry。
