You can't wash your hair without shampoo. First of all, the scalp will secrete oil day and night, a small amount of oil can play a certain protective role on the scalp, but excessive oil secretion or a few days do not wash hair caused too much oil, it is easy to cause hair follicle blockage, and even cause hair loss. And need not shampoo only clear water is not good, grease is insoluble in water, must use shampoo ability to clean scalp and hair, maintain the healthy condition of the scalp.