There are many reasons for hair loss: 1, mental tension, tiredness, staying up late, stress, etc. can cause hair loss, usually improve this state, can gradually heal itself. 2, androgen overproduction, can also cause androgenic alopecia, often in middle-aged men, generally need anti-androgen treatment. 3, seborrheic alopecia, is a kind of hair loss on the basis of seborrhea, often accompanied by an increase in dandruff, hair It is often accompanied by an increase in dandruff, rapid oiling of the hair, itching, etc. It is necessary to wash the hair diligently, use topical drugs to remove oil, and eat less spicy and greasy food. 4. Alopecia areata is a kind of hair loss with limited immune dysfunction.