Symptoms of vitamin D deficiency vary by age, from skeletal dysplasia and motor retardation in childhood, to osteochondrosis and skeletal deformities in adulthood, and osteoporosis in old age. Vitamin D deficiency is more likely to occur in childhood, especially in infants. Generally, it can be manifested as night terrors, excessive sweating, sleep disturbances and other symptoms of increased neural excitability, which in turn lead to skeletal developmental abnormalities, such as softening of the skull, delayed closure of the fontanel, and delayed eruption of teeth. It even tends to lead to delayed motor development, which is manifested in conditions such as decreased muscle strength and tone. Vitamin D deficiency in adulthood can lead to osteochondrosis, causing low back and leg pain, as well as pressure and pain in large joints such as the sternum and ribs. It can also cause skeletal deformities such as a sunken head, hunchback, and thoracic ectopia. For elderly patients, vitamin D deficiency is prone to osteoporosis, which can cause pain, soft tissue swelling, abnormal joint movement, and easy fracture without obvious reasons or slight external force. It is recommended that once the diagnosis of vitamin D deficiency is confirmed, it should be supplemented according to the doctor’s instructions in order to avoid delaying the condition.