Children do not consume adequate amount of nutrition and the imbalance of diet causes nutritional deficiency, so it is the main cause of low immunity in children. Immunity is the body’s own defense mechanism, which is the body’s ability to recognize and eliminate viruses, bacteria, etc., and can identify and deal with mutated cells and virus-infected cells. There are different types of immune deficiency, most of which are temporary and usually improve after 1-2 years, and most physiological immune deficiencies do not require special treatment. Most physiological immune deficiencies do not require special treatment. By strengthening and balancing the child’s nutrition, doing aerobic exercise and maintaining a good mood, the child’s immune status will be significantly improved. For children with more severe manifestations of immune deficiency, it is necessary to visit the pediatric department of a regular tertiary care hospital. It is not recommended to blindly use immunity-boosting drugs or health supplements. It can be adjusted from the diet, such as more bone broth, chicken soup, fish soup, seafood, fresh fruits, vegetables and fruits, deep-sea fish, nuts, flaxseed oil, sunflower oil, etc.. You can also eat more citrus fruits rich in vitamin C can also improve their immunity. Do not eat spicy and greasy, drink more plain water. Also need regular rest, need 8 to 10 hours of sleep every day, usually can run with the child to play ball, swimming and other outdoor sports, will make the child’s immune function gradually mature.