According to Regulation 1223/2009 on cosmetic products in EU, the term cosmetic refers to any substance or mixture intended to be placed in contact with the external parts of the human body (epidermis, hair system, nails, lips, and external genital organs) or with the teeth and the mucous membranes of the oral cavity with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance, protecting them, keeping them in good condition or correcting body odors. The skin delivery system is used to carry active ingredients and promote the controlled and targeted delivery of active ingredients. The active components are effectively fed into the active site by the percutaneous permeation system to enhance the efficacy of the active components, for example, vitamin A alcohol, vitamin C, niacinamide, salicylic acid, thereby achieving the effects of whitening, antioxidation, and so on. For the purpose of cosmetology, the main problem of absorption of cosmetics is to allow the active ingredients to act on the surface of the skin and to avoid absorption into the bloodstream and the whole body.Only with a thorough understanding of the skin can we develop safer, more stable techniques to promote penetration. The legal and regulatory issues that come along with the rise of various penetration promotion technologies also require the efforts

Background Epigenetics has recently evolved from a collection of diverse phenomena to a defined and far‐reaching field of study. Epigenetic modifications of the genome, such as DNA methylation and histone modifications, have been reported to play a role in some skin diseases or cancer. Aims The purpose of this article was to review the development of epigenetic in recent decades and their applications in dermatological research. Methods An extensive literature search was conducted on epigenetic modifications since the first research on epigenetic. Results This article summarizes the concept and development of epigenetics, as well as the process and principle of epigenetic modifications such as DNA methylation, histone modification, and non‐coding RNA. Their application in some skin diseases and cosmetic research and development is also summarized. Conclusions This information will help to understand the mechanisms of epigenetics and some non‐coding RNA, the discovery of the related drugs, and provide new insights for skin health management and cosmetic research and development.