Children who can eat a balanced diet do not need to take extra calcium supplements, and will be advised to take calcium supplements when they are deficient in calcium. If the child can achieve a balanced diet, most of the food can be able to intake a sufficient amount of calcium, such as milk, lean meat, soy products, vegetables can be intake of calcium, there is no need for additional calcium supplements. Due to insufficient intake of vitamin D in food, vitamin D deficiency may affect calcium and phosphorus metabolism, resulting in vitamin D deficiency rickets. It is recommended to take vitamin D as prescribed by the doctor after two weeks of birth to promote calcium absorption to ensure bone development and prevent rickets. Children try to achieve a balanced diet during growth and development, timely supplementation of vitamin D, most of the symptoms of calcium deficiency will not occur, without additional supplementation, if necessary, go to the hospital to consult a doctor.