Children aged 7-12 can take calcium supplements under doctor’s guidance if their bodies lack calcium. There are many kinds of calcium supplements, such as calcium carbonate, calcium acetate, vitamin D, etc., which are analyzed as follows: 1. Calcium carbonate: Calcium carbonate is a kind of calcium supplements used in hospitals, which can supplement the calcium needed by children’s bodies, and some children may suffer from constipation and bloating after taking it. 2. Calcium acetate: Calcium acetate also has a relatively large role in calcium supplementation, it is recommended to take between meals to reduce gastrointestinal stimulation. 3. Vitamin D: Vitamin D is mainly to help calcium absorption, if only simple calcium supplementation, no vitamin D supplementation, may affect the absorption of calcium. In addition to medication to supplement calcium, if children’s calcium deficiency is not serious, it is recommended that dietary supplements, such as eating more dairy products, soy products and shrimp.