A bag on the chest may be caused by folliculitis, keloid, breast hyperplasia and other reasons. 1. Folliculitis: part of the population belongs to the oily skin, hot weather, a lot of exercise and other cases of sweating without timely cleaning, may lead to metabolic products accumulate in the chest follicles, the chest on the long bag situation. 2. keloid: they belong to the keloid body, the skin of the chest area is damaged or inflammation stimulation of the growth of granulation tissue. After the injury or inflammation subsides, the localized area becomes keloid, and the gradual development of keloid may form keloid. 3. Breast Hyperplasia: Breast hyperplasia such as ductal epithelial and alveolar epithelial hyperplasia may lead to breast lumps, and a few people may have painful symptoms. If you have a breast pouch, it is recommended to go to the hospital in time for a clear diagnosis and correct treatment under the guidance of the doctor. Daily attention should be paid to diet, avoid spicy and stimulating foods, and strengthen physical exercise in moderation.