White hair occurs when the melanin is not formed in the papilla and no color pigment is present in the cortex. Single white hairs can start quite young, between twenty and thirty years of age. It is hereditary and quite rare. Other causes of white hair can be worry, shock or severe illness. White hair appears prominent and noticeable because they tend to be more wiry. Removing the odd one won't hurt. Color can't be restored once it has gone, but coloring on white hair can often be more interesting than on original color.