Frequent acne on the back of the head is related to the following points. First, abnormal sebaceous gland secretion, that is, excessive oil production. Second, it is related to infection caused by Acinetobacter and other atypical bacteria or fungi. Third, it is related to the daily diet, such as long-term consumption of food with too much oil. Fourth, the probability of acne in people with combined diabetes is also significantly higher than normal. The actual fact is that you will need to avoid spicy, sweet and fried foods, try to wash your hair with Kang Wang and selenium disulfide, and if conditions permit, you can go to the dermatology department for an examination and check the follicle mirror to see if there is inflammation and infection in the follicle area.