Acne is one of the most common dermatologic diseases affecting 40 to 50 million people in the United States, most of who are adolescents and young adults. In addition to the well-recognized physical sequelae of this condition, several studies have linked severe acne to considerable social impairments and serious psychological conditions including suicidal ideation and major depression. Furthermore, severe acne has been recognized in some studies as a risk factor for breast cancer, suggesting that these conditions may have common causes. Little is known about the role of diet in the pathogenesis of acne. Recent analyses of the Nurses’ Health Study II and the Growing-Up Today Study suggest that high intake of milk increases the risk of developing acne during adolescence. Despite the consistency of findings between these two studies, they cannot be regarded as conclusive and further research is needed in this area. Establishing the nature of the association between milk intake and acne can have broad clinical and public health implications. It could enhance the currently existing therapeutic options for the treatment of acne. More importantly, public health recommendations regarding milk and dairy intake could be designed in order to prevent its effects on the sebaceous glands and probably other hormone sensitive glands like the breast.