Back acne refers to acne, a chronic inflammatory skin disease of the sebaceous gland unit of the hair follicle, which is mainly related to factors such as genetic factors, skin structure, poor diet and bad daily habits. 1. Genetic factors: acne, also known as acne vulgaris, has a certain genetic predisposition, and for people with similar diseases in their family, the chances of reoccurrence will be higher. 2. Skin structure: The back of the skin is also an area where the sebaceous glands secrete abundantly, so it is also a favorable area for acne. 3. Bad dietary habits: people who like spicy and stimulating foods as well as greasy foods will have a significant increase in sebum secretion, which will increase the incidence of acne. 4. Poor daily habits: People who have an irregular daily routine for a long time or do not pay attention to hygiene will have a higher chance of being infected with Propionibacterium acnes, so the incidence of acne will also increase. Due to the many factors affecting acne, it is necessary to have a doctor’s consultation and analyze the specific situation with other medical history.