45 years old hair white can be normal physiological changes, but also may be related to psycho-neurological diseases or vitiligo and other reasons, can be black according to the cause and treatment effect of different differences, if the lack of effective treatment drugs, can be through the dyeing of hair to make the hair black. 1. old age gray hair is often a physiological change, due to ageing hair follicle melanin production is reduced, can gradually appear white hair increase, at this time the white hair is generally not black, if necessary, can be improved through the coloring of hair white hair. 2. Some neuropsychiatric diseases such as anxiety, emotional stress, nerve trauma or neuralgia and other reasons can also prompt the 45-year-old patient’s hair partially or completely white, at this time, the lack of effective treatment drugs for gray hair, but for the beauty of the choice of white hair with hair dye black. At the same time to adjust the mind in time, keep a good mood every day. 3. Vitiligo as an acquired pigment loss skin and mucous membrane disease, involving the head and facial hair, can be seen white hair, but after treatment, with the condition of the control and improvement, scalp white spots will turn normal, and white hair can also become black hair. It is recommended to pay attention to rest, avoid staying up late and ensure regularity of life, good mood, gray hair caused by pathological factors or accompanied by its clinical manifestations, consult a doctor as soon as possible, and comply with the doctor’s instructions for treatment.