Oily skin is characterized by a shiny and glossy skin, primarily in the T-zone (forehead, nose, and chin). This results from an overproduction of sebum by the sebaceous glands. The activity of the sebaceous glands is under hormonal control, so the primary cause of hyperseborrhea is hormonal factors.
Note : Sebaceous glands are accessory glands of the epidermis responsible for the secretion of sebum. They are present on the entire surface of the skin (at the dermis level) except on the palms of the hands and the soles of the feet (hairless areas).
Sebum is a complex mixture of lipids that make up the hydrolipidic film. Its role is to protect the skin from external aggressions. Moreover, it helps to maintain the hydration of the epidermis and prevent insensible water loss. Therefore, sebum is essential for the skin's good health.
However, when sebum is secreted in excess, it can lead to skin discomforts such as the appearance of acne. Indeed, the sebum can clog the pores, which are the openings of the sebaceous glands on the skin surface. This fat-rich environment is conducive to the proliferation of the bacteria responsible for the onset of acne, Cutibacterium acnes (formerly Propionibacterium acnes), which primarily feeds on sebum. This bacteria secretes pro-inflammatory substances that cause inflammation and the formation of pimples.
In order to combat skin discomfort associated with excessive sebum secretion, the use of cosmetics containing lactic acid can prove to be beneficial.