Blackheads, also known as open comedones, are retentional lesions that resemble small dark bumps. Often found on oily skin, they form when an excessive amount of sebum or dead cells clog a pore, creating a plug within the hair follicle. As a result of this accumulation, the pore widens, exposing the sebum to air which oxidizes it and gives it its characteristic black color. 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 trigger hyperseborrhea and slow down 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 helps to more effectively remove dead cells, thus reducing pore obstruction and the formation of open comedones.
It's important to note that retinol is not strictly an exfoliant: its influence on the removal of cells from the stratum corneum is only indirect. Concurrently, retinol is often described as a regulator of sebum production. While this property has been extensively demonstrated in vitro, clinical studies on this aspect remain limited.
Retinol appears to be a relevant active ingredient for reducing blackheads as it accelerates cell renewal, thus limiting the buildup of dead cells that clog 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.
Reduction in lesions following the application of a formulation based on retinol, sodium ascorbyl phosphate, or a blend of the two active ingredients.
Source: NATAKANKITKUL S. & others. A comparative study of the clinical effectiveness of sodium ascorbyl phosphate, retinol, and their combination in the treatment of acne. International Journal of Cosmetic Science (2009).
More clinical studies are needed to confirm the effectiveness of retinol against blackheads, although several factors suggest its potential.