Acne is also known as acne vulgaris, and forehead acne is considered to be related to heredity, diet, keratinization of follicular sebaceous gland ducts, and endocrine factors. 1. Heredity: The occurrence of acne is directly related to heredity, and there is a tendency for family aggregation. For example, if grandparents or parents often have acne when they are young, their children are prone to acne on the forehead due to the influence of genetic factors. 2. Diet: Everyone’s diet is different. Frequent intake of sugary, high-fat and fried foods may lead to increased secretion of the sebaceous glands, which may cause acne-like changes on the forehead if the follicle openings are blocked. 3. Keratinization of follicular sebaceous gland ducts: Increased sebaceous gland secretion, if the follicular opening is excessively keratinized, resulting in too small an opening, it will have an impact on sebum discharge, resulting in localized acne. 4. Endocrine factors: changes in hormone levels during puberty and before menstruation, such as high levels of androgens, may increase sebaceous glands and sebum secretion, leading to forehead acne. It is recommended to pay attention to the care of life and diet, if the symptoms are obvious, if necessary, go to the hospital dermatology department for examination, and give standardized treatment to help relieve the symptoms.