According to recent studies, normal people lose 50-100 hairs per day, so a few hairs falling out with a scratch is usually within the normal range and can be done without too much worry. However, if the number of hair scratched down is higher or easier to fall out, it may be caused by recent stress, long-term eating disorders, etc. However, it may also be caused by disease factors: 1, resting hair loss: can be caused by a variety of stress factors to prematurely enter the resting phase of a large number of hair, resulting in an increase in the amount of hair into the regression phase, and then the phenomenon of increased hair loss, a scratch to lose a few roots. Common stress factors include excessive dyeing and perming, inadequate nutritional intake, postpartum, anemia, etc. Hair loss is generally diffuse, shedding from the roots and temporary hair thinning occurs; 2. Androgenetic alopecia: androgenetic alopecia is an androgen-dependent genetic hair loss disease. Patients with the top of the head hair progressive thinning, thinning, and then fall off as the main pathological characteristics, but other parts are generally not involved; 3, folliculitis: if the head of the scalp occurs folliculitis, when scratching the hair is easy to cause hair loss performance, in addition, there may be itchy scalp, red and swollen symptoms; 4, thyroid disease: thyroid gland dysfunction patients can appear symptoms of hair loss, when scratching the hair That is, it can fall out. And too much or too little thyroid hormone will affect the normal metabolism of the body, as well as the normal growth of hair. In addition to hair loss, patients may also have pain in the thyroid area and may experience general symptoms such as chills and weakness. Patients are advised to minimize hair damaging moves such as hair dyeing, perming and bleaching, and avoid using irritating hair care products on a daily basis. At the same time should maintain a relaxed, happy state of mind, stay up late, anxiety and other negative behavior does not have a positive effect on hair care. If the symptoms of hair loss when scratching hair are serious or affect your daily life, you can go to the hospital for professional diagnosis and treatment.