Hair loss may indicate diseases of the body such as malnutrition, androgenetic alopecia, baldness and scalp infection. 1. Malnutrition: If there is picky eating, partiality and other bad dietary habits, it may lead to malnutrition, resulting in malnutrition alopecia, because of the lack of nutrients in the body, resulting in the hair root is not strong, the hair follicles in the hair growth of nutrients required for a serious shortage of hair loss, thus causing hair loss, this kind of patients may also occur in the face of yellow muscle thinness, fatigue and sleepiness and other symptoms. 2. Androgenetic alopecia: androgenetic alopecia, also known as seborrheic alopecia, is a common disease that causes hair loss, baldness, hairline shift, its possible pathogenesis is that scalp follicles are too sensitive to the role of androgens, so you can use finasteride, cyclopropylprogesterone and other medications to regulate the level of hormones, and based on this, topical minoxidil to help hair growth. 3. Patchy baldness: If, on the basis of severe hair loss, there are multiple patches of hair loss on the scalp with clear boundaries, then it may indicate the occurrence of patchy baldness, which may be related to autoimmune, genetic, endocrine and other factors, and the hair loss site is generally no scarring and inflammatory reaction, which can be treated with the help of Minoxidil, glucocorticosteroids, such as Prednisone, and other medications. 4. Scalp infection: Fungus, bacteria and other microbial infections of the scalp may cause ringworm of the scalp, baldness folliculitis and other diseases, thus damaging the hair follicles, causing hair loss, itching, redness, swelling, pain and other symptoms. It is recommended that patients with severe hair loss go to the hospital to clarify the cause of the disease and receive timely treatment to avoid further aggravation of the condition.