One of the common traits associated with growing old is gray hair. As we age, the melanocytes that contribute the pigment, melanin, to our hair stop producing, causing hair to become more transparent, or "gray." In fact, without any melanin, hair would appear white. Although gray hair may be normal for an adult, it might not seem so typical for a child. However, it is possible for children of all ages to grow a few gray hairs of their own.
One of the leading causes of gray hair in children is a genetically determined, premature maturational schedule. Research conducted in Australia published in the 2005 issue of the "Journal of Investigative Dermatology Symposium Proceedings" discovered a weak, yet positive correlation between a history of dandruff and gray hair. This does not mean that one causes the other; however, as dandruff frequency increases so does the likelihood of gray hair. Also, the study found the prevalence of gray hair jumped from 18 percent to 60 percent from ages 25 to 35 with much smaller, unreported rates in children.
Caucasians are more affected by gray hair than other children, generally with a few scattered gray hairs than full-out graying. According to Dr. Greene.com, a family history of early onset gray hair usually foreshadows its potential for development in offspring. Nonetheless, there is not enough research to say for certain which genes or on which side of the family gray hair is inherited from.
Certain childhood skin disorders like vitiligo, tuberous sclerosis, Waardenburg syndrome and neurofibromatosis have been indicated to induce the loss of hair pigmentation. Along with the symptom of graying hair, children with these conditions exhibit signs of seizures, hearing loss and tumors. Another cause of early graying is an overactive or underactive thyroid condition such as Grave's disease or Hashimoto's disease.
Vitamin B12 Deficiency
A deficiency in vitamin B12 is heavily tied to gray hair. Because most food products made from animals provide more than a sufficient supply of vitamin B12, graying is rarely due to a nutritional deficiency. On the other hand, children who follow strict vegan diets may fall under this category. Also, children who have had surgery in which the stomach cannot adequately digest and absorb vitamin B12 may be affected. To remedy this cause, parents should administer children a vitamin B12 supplement.
Contrary to popular belief, stress does not cause graying. Little scientific research has supported this claim. However, recent research published in the June 2009 issue of "Cell" magazine found that genotoxic stress---stress on the genes from ultraviolet light and radiation---may mutate hair cells, triggering early signs of graying.