The deficiency of zinc and lysine usually causes children's growth retardation, loss of appetite, anemia and malnutrition, anorexia, pica, oral ulcer and so on. Children are at high risk of zinc deficiency. It is reported that about13 children in the world are zinc deficient. Children sweat more than adults, and zinc in the body is lost with sweat. In addition, the hot weather and loss of appetite also make zinc not replenished in time, making summer a high incidence season for children's zinc deficiency.
According to the eating habits of China residents, food protein usually comes from cereals. However, the content of lysine in grain is less, and because lysine is easily soluble in water and easily lost during cooking, it is difficult for a simple diet to meet the needs of human growth.