Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, stiff muscles, weak muscles, and tremors. There may be problems with sensation, vision, hearing, and speaking. Often, babies with cerebral palsy do not roll over, sit, crawl or walk as early as other children of their age. Other symptoms include seizures and problems with thinking or reasoning, which each occur in about one-third of people with CP. While symptoms may get more noticeable over the first few years of life, underlying problems do not worsen over time.Cerebral palsy is caused by abnormal development or damage to the parts of the brain that control movement, balance, and posture. Most often, the problems occur during pregnancy, but they may also occur during childbirth or shortly after birth. Often, the cause is unknown. Risk factors include preterm birth, being a twin, certain infections during pregnancy, such as toxoplasmosis or rubella, exposure to methylmercury during pregnancy, a difficult delivery, and head trauma during the first few years of life, among others. About 2% of cases are believed to be due to an inherited genetic cause. A number of sub-types are classified, based on the specific problems present. For example, those with stiff muscles have spastic cerebral palsy, those with poor coordination in locomotion have ataxic cerebral palsy, and those with writhing movements have dyskinetic cerebral palsy. Diagnosis is based on the childs development over time.
It is also considered reasonable to treat at-risk persons with vitamin D supplementation without checking the level of 25(OH)D in the serum, as vitamin D toxicity has only been rarely reported to occur.Levels of 25(OH)D that are consistently above 200 nanograms per milliliter (ng/mL) (or 500 nanomoles per liter, nmol/L) are potentially toxic. Vitamin D toxicity usually results from taking supplements in excess. Hypercalcemia is often the cause of symptoms,  and levels of 25(OH)D above 150 ng/mL (375 nmol/L) are usually found, although in some cases 25(OH)D levels may appear to be normal. Periodic measurement of serum calcium in individuals receiving large doses of vitamin D is recommended. Screening
The official recommendation from the United States Preventive Services Task Force is that for persons that do not fall within an at-risk population and are asymptomatic, there is not enough evidence to prove that there is any benefit in screening for vitamin D deficiency. Treatment
UVB exposure
Vitamin-D overdose is impossible from UV exposure: the skin reaches an equilibrium where the vitamin degrades as fast as it is created. Sun tanning
Light therapy
Exposure to photons (light) at specific wavelengths of narrowband UVB enables the body to produce vitamin D to treat vitamin D deficiency. Supplement
In the United States and Canada as of 2016, the amount of vitamin D recommended is 400 IU per day for children, 600 IU per day for adults, and 800 IU per day for people over age 70.