There are many symptoms that can reflect whether the newborn is calcium deficient, parents need to carefully observe when caring for their newborn, the main manifestations of calcium deficiency are: 1. Initially, the main manifestations are increased neuroexcitability: such as irritability, irritability, loss of appetite, sleep disturbance, night awakening, excessive sweating, occipital protrusion, etc. Mental irritability and disinterest in the surrounding environment. The infant does not fall asleep easily and is less likely to fall into a deep sleep. And the infant sweats a lot, cries and wakes up easily after falling asleep. It is often manifested as excessive sweating, not related to temperature, especially sweating on the head after sleep, which makes the infant’s head rub the pillow continuously, and the occipital bald circle can be seen behind the skull after a long time. 2, the skeletal system can appear cranial softening: easy to lead to forehead hypertelorism, the formation of square skull. 3. Convulsions can occur: they occur suddenly, usually without fever, and are characterized by upturned eyes, tremors of facial muscles, twitching of limbs, and loss of consciousness in severe cases. Duration of a few seconds to ten minutes, once a few days or several times a day varies, the seizure stops after the lively as usual. 4, hand and foot twitching: newborns with severe calcium deficiency can occur hand and foot hand and foot twitching, episodes of consciousness, double wrist flexion, fingers straight, thumbs close to the palm, foot spasms when both lower limbs straighten inward, toes bent downward into an arch. 5, beaded ribs: due to lack of vitamin D, rib cartilage hyperplasia, each rib cartilage hyperplasia connected like a string of beads, often compressing the lungs, so that infants have poor ventilation, prone to bronchitis, pneumonia. The correct way to supplement calcium is to first adjust the diet, calcium intake from the diet is the most important way to supplement calcium, but also the safest way. Severe cases require prompt hospital consultation and intravenous infusion of calcium.