According to CNN Health contributor Dr. Jennifer Shu, the development of gray hair in children is usually genetic, but it is also caused by a nutrient deficiency or a skin disorder. Dr. Shu also notes that if a child's general health is normal, early graying is not a cause for concern.
A vitamin B-12 deficiency sometimes causes gray hair in children, according to Dr. Shu. This vitamin is found in many animal products, including meat, eggs, fish and milk. If the diet is not rich enough in this nutrient, a supplement form suffices.
Although rare, there are also certain medical conditions that cause premature graying, notes Dr. Shu. Thyroid hormone levels that are either too low or too high cause some children to develop gray hair. Have a doctor do blood work to check a child's hormone levels if a thyroid condition is suspected. Skin disorders, such as alopecia, vitiligo, tuberous sclerosis, neurofibromatosis and Waardenburg syndrome, also cause premature graying in children. These skin disorders are hereditary and are often accompanied by serious symptoms, including seizures or hearing loss. Pediatricians test children for these conditions if they run in a child's family. WebMD explains that genetics play a large role in determining when a person's hair goes gray.