Acne vulgaris is a chronic inflammatory skin disease of the follicular sebaceous gland units, and the pathogenesis remains incompletely elucidated. Genetics, androgen-induced sebum production in large amounts, follicular sebaceous gland duct keratinization, Propionibacterium acnes colonization, and immune inflammatory response may all be involved. The onset of some patients is also influenced by genetic, immune, endocrine, emotional and dietary factors. It is important to limit the intake of foods with high glycemic index and milk that may trigger or aggravate acne, keep bowel movements clear, and avoid staying up late.