You can judge whether it is normal or not by the amount of hair loss, the density of hair, and the accompanying symptoms. 1. The amount of hair: the human body has to carry out metabolism every day, hair also exists in the growth period, degeneration and resting period, normal people lose 70-100 hairs per day on average, if more than this amount and persistence is abnormal hair loss. 2. Hair density: if the patient is dense hair loss, hair loss after the emergence of flaky hair loss, also belongs to abnormal hair loss, need to go to the hospital in a timely manner to diagnose whether baldness, and actively take treatment measures. 3. Accompanying symptoms: normal alopecia is usually not accompanied by conscious symptoms, but if hair loss is accompanied by itchy scalp, thinning hair, soft hair, dry and frizzy hair and other abnormal manifestations, it also belongs to abnormal alopecia. If the patient has self-conscious symptoms, he can go to the hospital for examination, and the doctor will conduct hair pulling test to determine whether there is abnormal hair loss through the amount of hair loss, so as to clarify the pathological factors as early as possible, and take targeted intervention measures in time, so as to avoid worsening of symptoms caused by the delayed condition.