Protein can be divided into 2 parts according to the source. For example, animal proteins: The proteins that are found in the animal kingdom are called animal proteins. Such as: fish , meat , eggs , milk etc. This protein is called first class protein. Vegetable proteins: Proteins obtained from the plant world are called vegetable proteins. Such as: pulses , nuts , soybeans , bean sprouts etc. Vegetable proteins are called second class proteins. One kilogram of protein provides four kilocalories of energy. 20-25% of daily required calories should be taken from protein foods. In addition to vegetable protein, some animal protein should be taken in the daily diet. Our body is made up of proteins from bones , muscles , various organs , blood cells to teeth , hair , nails. Protein promotes the physical growth of children and builds the body. The cells of our body are constantly eroded. Proteins play a role in repairing and repairing wounds by forming new cells in the affected area. When the body is deficient in fats and carbohydrates, the protein works to produce heat energy. Proteins make important antibodies in our body to fight pathogens. Protein is essential for mental development or brain development. Lack of protein in the body disrupts the normal growth of growing children.