Why is there always acne on your forehead?

Acne is a chronic inflammatory skin disease of hair follicle sebaceous glands, which occurs in young men and women aged 15 to 30. Cheeks and forehead are the most common sites for acne, followed by mandible, chest and back. Acne is also the most common site for acne. The onset of acne is related to four major causes: increased androgen and sebum, excessive keratosis of hair follicle sebaceous glands, infection of Propionibacterium acnes and secondary inflammatory reactions. The occurrence of acne is also related to genetics, immunity, endocrine disorders, mood, diet, cosmetics and other factors. The main treatment principles for acne are to remove fat, dissolve keratin, sterilize, reduce inflammation and regulate hormone levels.