Long gray hair is the hair all white or partly white, gray hair is generally divided into two kinds of congenital gray hair and acquired gray hair. The causes of acquired gray hair are mainly the following: first, genetic factors, some patients have a family history, indicating a certain relationship with genetics; second, mental and neurological factors, mental tension, emotional distress, frightened, anxiety, insomnia, worry, etc. can cause gray hair; third, poor dietary habits, unreasonable diet, resulting in impaired synthesis of hair follicle melanocytes, causing gray hair; fourth, environmental pollution; fifth , age factor, as we grow older, the hair follicle melanocytes will gradually decline, causing the hair to turn white; six, Chinese medicine believes that there is a certain relationship with the liver, spleen and kidneys.