The manifestations and symptoms of zinc deficiency in children include impaired digestive function, backward growth and development, reduced immune function, delayed intellectual development, and other manifestations. 1. Reduced digestive function: zinc deficiency can inhibit the activity of gastro-salivary phosphatase, and also cause hyperplasia and hyperkeratosis of the tongue mucosa, thus leading to decreased sense of taste, anorexia and lack of appetite. 2. Backward growth and development: zinc deficiency can affect the maturation of the gonadal axis and inhibit the function of the growth hormone axis, and the affected children will show delayed sexual development, short stature, and delayed growth and development. 3. Reduced immune function: zinc deficiency can affect the immune system, so children are prone to recurrent infections. 4. Delayed intellectual development: Zinc deficiency affects protein synthesis in the brain, so zinc-deficient babies can have delayed intellectual development. 5. Others: e.g. xerophagia, recurrent mouth ulcers. When the above symptoms occur in children, parents should take them to the hospital in time, and standardize the treatment under the guidance of doctors.