Every cell in the body contains proteins and they are made up of units called amino acids. Essential amino acids must be supplied by the diet because the body cannot make its own supplies. The other amino acids are called non essential amino acids and they can be synthesized by the body fast enough to meet its needs. Proteins which contain all eight essential amino acids are complete proteins and they will help the growth and maintenance of body tissues.
Proteins provide amino acids which the body needs to grow, form new tissue, maintain and repair body tissues. They also help in forming enzymes, hormones, and antibodies and provide energy. A person needs protein according to their age, body size, quality of proteins in their body, and physical state. Protein is found in meats, fish, milk and cheese. Protein provides the foundation for most of the body's tissues, nerves, internal organs (including the brain). Proteins are used to make neurotransmitters and essential to improve mental performance ("Brain Food", 2009)If the diet does not contain enough protein lack of energy, tiredness, and loss of weight may occur a child's growth may be stunted.