Acne is a common and widespread problem, and after acne on the back, it is difficult to manage its beauty, no matter how nice the clothes are, after wearing them. And back acne is extremely difficult to deal with, if not handled properly is very easy to leave acne marks. So do you understand the causes of back acne? The back is a blind spot for sight, it is difficult to cutty clean when bathing, plus if the moisture is not sucked dry after bathing, it is easy to make clothes close to the body and breed bacteria. Bacteria invade the pores and begin to multiply, they will be blocked in the sebaceous ducts along with the oxidized sebum, leading to acne outbreaks. 2. bed cleaning is not in place bed sheets and covers tend to accumulate unclean dust, bed cleaning is not in place, unclean dust blocking the pores of the back, so that the oil formed acne. 3, back sweating is not processed in time Due to the heat, a little movement, it is easy to sweat, sweat will soak clothes, sweat should be discharged with sweat toxins and impurities will be attached to the surface of the skin, blocking pores, the formation of acne and other problems. 4, lung heat The back is the reflex zone of the lungs, lung heat or meridian is not working will cause back acne. If you gather in the upper part of the back, the middle part of the two shoulder blades, it is lung heat, eat some laxative fire can also help slow down acne. Skin allergies Skin allergies can cause acne on the back, so usually do not let the skin contact allergens. If you are allergic, you should avoid contact with allergens in your daily life so as to avoid acne.