Life Health Sciences – Science Rules it All

Proteins are made up of carbon, hydrogen, oxygen and nitrogen. Sulphur may also be present in small amounts in the proteins. All the proteins are made up of smaller units called amino acids. The proteins we eat in our diet are not absorbed as such. They are broken down to amino acids by the protein digesting (proteolytic) enzymes in the digestive system. Amino acids then absorbed from the intestine. There are 24 different amino acids in nature and of these only 20 amino acids present in most of the proteins. Based on our requirements, amino acids have been divided in to two groups. The first groups of amino acids are called ESSENTIAL AMINO ACIDS and the second group is known as NON-ESSENTIAL AMINO ACIDS. There are nine essential amino acids – isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine and histidine. Our body cannot synthesize these amino acids. It is essential that these amino acids should be present in sufficient amounts in our diet. Therefore, they are called essential amino acids. Histidine is essential amino acid only for infants but not for adults (adult humans can synthesize sufficient amount of histidine). In the absence of essential amino acids growth and development will not be normal.