Hair loss when washing hair, within a certain amount, is a normal phenomenon, because the hair is in a process of growth, regression and resting period every day. It is normal to lose about 100 roots per day, especially in autumn and winter. If it is beyond this range, pathological hair loss, such as androgenetic alopecia (also called seborrheic alopecia), should be considered. There is also acute and chronic resting alopecia, which may be related to abnormal hormone levels in the body. Also, like acute and chronic resting hair loss, many have irritating factors, such as major illness, surgery, and postpartum, which have some relationship. So, to lose a lot of hair, look at the number of hair loss; then find out the density of hair, whether it is decreasing, and go to a comprehensive judgment. If necessary, you must go to the hospital to see.