The first thing to consider is whether there is vitiligo, vitiligo is a disease related to autoimmunity, the disease and genes and other factors are also related, if it is vitiligo, the disease may be progressive development, it is recommended to first improve the Wooden lamp examination to exclude vitiligo. It may also be physiological, generally with the growth of age, the hair will gradually appear local whitening, this situation will not need special treatment, observe the changes can. The other condition considered is intradermal nevus, some invasion is deeper, there will be longer hair on the surface of the nevus, generally the depth of invasion will reach the dermis or subcutaneous fat layer, these parts are the parts where the hair follicles are located. If the hair is born at a certain age, it may also be white in color, which is also a normal phenomenon and does not require special treatment.