Immunity characteristics often show that the immune system is not developed enough, the function is still not perfect; coupled with the usual diet is not good, may lead to children’s immunity is relatively low, the diagnostic criteria are as follows: 1, for children under six years old, an average of 6 to 8 times a year will be very normal, just started kindergarten elementary school children, sick 1 to 2 times a month is also very normal, so do not worry, but if always But if the child is always sick, accompanied by growth retardation; 2, each time he or she is sick, he or she is not able to relieve himself or herself and needs intravenous fluids or hospitalization; 3, each time a bacterial infection, he or she has to use antibiotics for more than two months, and the effect is not good; 4, each time the child is sick is a serious infection, such as meningitis or sepsis, he or she should go for an immunity test to see if there is a relatively low immunity, or deficiency. If the immunity is simply low, the following treatments are given: (1) Eat more foods containing vitamin C, such as potatoes, oranges, kiwis, tomatoes and the like, as well as mushroom foods, such as enoki mushrooms and apricot mushrooms. (2) more physical exercise with children, such as going to more open squares, more sun, jogging, playing ball can enhance resistance; (3) if the resistance is very poor, we can give him with nutritional drugs, such as Yu Ping Feng particles or spleen amin peptide or health products, such as: lactoferrin protein powder, this can be taken continuously for 2 to 3 months About the time.