Hair becoming dry and rough may be related to physiological factors such as frequent hair coloring, or diseases such as malnutrition and iron deficiency anemia. 1. Physiological factors: physiological factors such as frequent hair coloring or staying up late may cause hair to become dry and rough. 2. Malnutrition: the cause of the disease is mostly related to insufficient or imbalanced intake of nutrients, consumption dysfunction and other factors, clinical manifestations of weight loss, emaciation and hair dry and yellow phenomenon, and some patients may have hair become dry and rough. 3. Iron deficiency anemia: its cause is mostly related to the imbalance of iron absorption and excretion in the body, which is mainly manifested as pale skin, dizziness and dry hair and other symptoms. The cause of hair becomes dry and rough is not a reason, in the exclusion of physiological factors, it is recommended that the patient to consult a doctor for examination, to clarify the cause of the disease, and follow the doctor’s instructions for treatment.