Brassiere is a necessary item for every woman to wear in life, however, incorrect wearing will not only bring protection to breasts, but also bring hidden danger to breast health. The incidence of breast cancer and non-lactating mastitis has increased 5-6 times in the past 100 years. In addition to human lifestyle, environmental pollution, genetic inheritance and other factors, improper wearing of bras is also to blame. How can we wear it correctly? As women, we must understand the right and wrong of bras. Yang Zejuan, Breast Surgery Department, Guangzhou Hospital of Traditional Chinese Medicine About the “yes” of bras: bras themselves are harmless, and the right bras are naturally helpful to the breasts. The support and fixation of breasts mainly depends on two roles, one is as the internal fixation of breast Cooper ligament, which connects the gland with the skin and keeps the shape; the other is as the external fixation of bra, which is mainly to help support breasts, and the two work together to prevent back and waist discomfort and sagging of breasts, and also to prevent swaying of breasts when walking or running. In addition, the right bra can not only support and support the breasts, protect the blood circulation of the breasts, but also protect the nipples from abrasions and bruises. For women in labor, a proper and clean bra will not only increase the amount of milk, but also prevent mastitis due to milk gathering infection. The “non” about bras: Are bras really essential? In 2003, Belgium had a study on female athletes aged 18-25 who did not wear bras. These female athletes were engaged in sports such as gymnastics, running and swimming. For the first 6 weeks, most of these women experienced discomfort during exercise, but the study found that their skin became tighter. After six months or so, the discomfort disappeared and the athletes felt more comfortable and at ease with their movements. Measurements a year later found that their breasts were firmer and more uplifted. French sports medicine doctors have been studying the effects of bras on women for 16 years and have also come to the conclusion that medically, physiologically, and anatomically, the rejection of gravity does not do any good for the breasts and that wearing a bra makes them sag more. Many cases have reported phlebitis and lymphangitis of the chest wall related to the wearing of overly tight bras, and it is unclear whether there is any relationship with the increased incidence of breast cancer. Therefore, when women who have been wearing bras for a long time take them off, the breasts without their own support system tend to sag. Therefore, women are advised to relax their breasts as much as possible and let them breathe freely, except on necessary occasions. The choice of bras should be based on breathable materials, and the bra and cups should be the right size to avoid being too tight. In addition, it should be changed regularly to ensure that the shape is appropriate.