Acne on the face is usually referred to as acne, a chronic inflammatory skin disease of the sebaceous gland units of the hair follicles, which can affect people of all ages, with a high incidence in adolescents. If you are in your forties and still have acne on your face, it may be related to genetic factors, increased sex hormones, diet and other reasons. 1. Genetic factors: People with a positive family history may have acne in their forties. 2. Increased androgens: High androgens can increase the size of sebaceous glands and sebum secretion. The increase of microorganisms such as Propionibacterium acnes in the hair follicles will hydrolyze the triglycerides in the sebum into free fatty acids, which will stimulate the proliferation of keratinocytes in the ducts of the hair follicles and over-keratinization of the keratinocytes, which will block the excretion of sebum, which will result in the formation of acne when sebum and keratin plugs are accumulated in the mouths of the hair follicles. 3. Diet: Eating too much high sugar, high fat or milk can also lead to acne in your forties. It is recommended that people with acne in their forties go to the hospital to get a clear picture of the cause of the problem and get standardized treatment under the doctor’s guidance.