The causes of gray hair include congenital factors, acquired factors, the former is mainly caused by some hereditary diseases, the latter includes natural aging, mental stress, malnutrition and related diseases and other factors caused. 1. Congenital factors. Mainly related to genetic diseases caused by genetic abnormalities, such as albinism, skin heterochromia – young cataract syndrome, etc. The onset of these diseases is usually related to genetic factors, and gray hair appears at an early age. 2. Acquired factors (1) Natural aging: for middle-aged and old people, gray hair is a normal physiological phenomenon, due to the decrease of melanocytes, resulting in the synthesis of melanin in the hair is also reduced, thus appearing gray hair. (2) Mental stress: For some people with long-term mental stress, it may lead to migration of melanocytes in the hair, insufficient blood supply to the scalp, endocrine disorders, and so on, thus causing an increase in gray hair. (3) malnutrition: if long-term partiality, hunger, suffering from digestive system diseases, etc., may lead to the body lack of nutrients, thus affecting the formation of melanin leading to gray hair. (4) Related diseases: including endocrine system diseases, such as hyper- or hypothyroidism; consumptive diseases, such as tumors, tuberculosis, etc.; vitiligo and other diseases, can also promote the growth of white hair, or involve the scalp follicles leading to local hair whitening. It is recommended that when the abnormal appearance of white hair, timely to the hospital, clear the relevant causes of disease, under the guidance of the doctor standardized treatment.