Blackheads, or open comedones, are retentional lesions that resemble small dark bumps. Often found on oily skin, they form when a significant amount of sebum or dead cells block a pore, creating a plug within the hair follicle. As a result of this accumulation, the pore widens, exposing the sebum to air which oxidises it and gives it its characteristic black colour. Most blackheads appear on the T-zone of the face, which includes the forehead, nose, and chin, where the concentration of sebaceous glands is highest. Genetic, hormonal, or environmental factors can cause hyperseborrhoea and a slowdown in cell renewal, processes that lead to the emergence of blackheads.
The retinol could be a promising solution for eliminating blackheads. Indeed, after application on the skin, it undergoes two enzymatic transformations to become retinoic acid, its active form. This latter interacts with specific receptors in skin cells, called RAR, for retinoic acid receptors, and RXR, for retinoid X receptors. By activating these receptors, it triggers a cascade of cellular signals that regulate the expression of certain genes involved in the differentiation of keratinocytes. This action contributes to more effectively removing dead cells, thus reducing pore obstruction and the formation of open comedones.
However, it should be noted that retinol is not strictly an exfoliant: its influence on the removal of cells from the stratum corneum is only indirect. In parallel, retinol is often described as a regulator of sebum production. While this property has been widely demonstrated in vitro, clinical studies are still limited on this point.
Retinol appears to be a relevant active ingredient for reducing blackheads as it accelerates cell renewal, thus limiting the build-up of dead cells that clog the pores.
Despite the intriguing action of retinol, clinical studies on its effectiveness against blackheads are currently limited. However, we can mention the study by NATAKANKITKUL and his team, which compared the effectiveness of a 0.2% retinol formulation, another containing 5% of sodium ascorbyl phosphate, a derivative of vitamin C, and a third containing both actives. This study gathered 45 participants suffering from acne and presenting, among other lesions, open comedones. Divided into three groups of fifteen people, these volunteers applied one of the formulations daily for eight weeks, resulting in a significant reduction in the number of lesions. However, the exact proportion of blackhead reduction was not specified, which limits the interpretation of the results, but these data are encouraging regarding the potential of retinol.