Hair growth cycle staging:anagen phase (3 years), regression phase (3 weeks), resting phase (3 months) A normal person can lose 70 to 100 hairs per day. Resting hair loss is the excessive loss of normal resting pestle-like hair caused by a variety of stressors. This type of hair loss most often occurs 3 to 5 months after the premature conversion of many anagen hairs to resting hairs. In general, a resting hair count of >25% of the hairs shed is a diagnostic indicator of resting hair loss, and >20% is a possible abnormality. There are many causes of resting hair loss, mainly the following: 1, endocrine changes such as hypothyroidism, postpartum or after the discontinuation of contraceptive pills. 2, long-term nutrient intake is insufficient, including calories, protein, essential fatty acids, zinc, iron intake is too low or lack of. 3, drugs such as antidepressants, angiotensinase converters, anti mitotic drugs (dose-dependent), beta-blockers, lithium, oral contraceptives, retinoids, etc. 4. Somatic stress conditions such as anemia, hyperthermia, allergic contact dermatitis due to hair dyeing, vitamin A augmentation secondary to renal dialysis patients, surgical procedures and mental stress. The clinical manifestation is diffuse hair loss, but rarely involves more than 50% of the hair. Patients find increased hair loss when combing or washing hair, mostly temporary thinning of hair, occasionally involving body hair, and some patients have painful hair loss with hair. Resting hair loss is most common in the postpartum period. During pregnancy, hairs can stagnate in the anagen phase for a long time without entering the resting phase as normal, and during childbirth, these hair follicles enter the resting phase at the same time, and the hairs start to fall out after 3 to 5 months. The hair follicles may be accompanied by depression, obsessive-compulsive personality disorder and anxiety. Histopathology: The number of hair follicles in the resting phase increases and the hair takes on a pestle shape. The hairs in resting alopecia are shed from the roots, and each shed hair is visible as a depigmented hair bulb-like structure, but without a root sheath. If a 4-mm diameter borehole biopsy is done, 20-25 hairs are visible in normal cross-section. If more than 12-15% of the terminal hair follicles are in the resting phase, it indicates that the follicles have significantly changed from anagen to resting phase. The number of resting hair loss can be estimated by pulling test or by asking the patient to collect and count the number of hair loss per day; a resting hair count >25% is the diagnostic criterion. There is no specific treatment for resting alopecia, the key is to find the cause and remove it. In most cases, hair loss stops on its own within 6 months to 1 year and hair can grow back. We should encourage a balanced diet, eat more black foods and nuts, appropriate psychological guidance, and can also use a combination of traditional Chinese medicine and Western medicine as the main treatment.