1. Clinical manifestations of zinc deficiency 1. Nutritional dwarfism Zinc deficiency can lead to loss of taste and appetite. At the same time, zinc deficiency will strengthen protein decomposition and decrease amino acid utilization, resulting in slow growth and short stature. 3. Slow growth of hair. This point is often overlooked by parents. For example, some children’s hair grows for more than half a year without treatment, which is likely to be caused by zinc deficiency. 4, white spots on the nails, finger barbs, map tongue (irregular red and white graphics on the surface of the tongue), repeated episodes of mouth ulcers, etc. 5, hyperactivity, slow reaction, inattention, poor learning ability. 6.Recurrent infections Repeated respiratory infections, such as tonsillitis, bronchitis, pneumonia, etc. 7.Inadequate development of secondary sex characteristics. Zinc deficiency leads to poor secondary sex characteristics because of low pituitary function and decreased gonadotropin levels in the blood due to zinc deficiency. The need for zinc and its sources is only 1.5 mg of zinc per day for infants aged 0-6 months and 8 mg for infants aged 7-12 months, after which the need for zinc increases slowly with age to a maximum of 19 mg at the age of 14-18 years. After puberty, the body’s need for zinc decreases, requiring only 11.5 mg per day. Animal foods are high in zinc and easily absorbed, so it is essential to add supplementary foods such as animal liver, egg yolk, minced meat and fish puree, which are rich in various trace elements, in appropriate amounts for infants and young children. In addition to animal foods, it is also important to eat more seafood such as oysters and nuts such as chestnuts and walnuts. When a child shows signs of zinc deficiency, parents should take the child to the hospital for a check-up, but do not supplement indiscriminately, as zinc overdose is also harmful. If zinc deficiency is not serious, dietary supplements are recommended.