RESUMEN
Retinol is a cosmetic ingredient that is structurally similar to all-trans-retinoic acid, which has been shown to be effective in the treatment of photodamage. Since skin keratinocytes are reported to metabolize retinol to retinoic acid, investigators have hypothesized that retinol may also be helpful in improving skin photodamage. In this eight-week, double-blind, split-face, randomized clinical study, a stabilized 0.1% retinol-containing moisturizer was tested (36 subjects) against the vehicle (28 subjects) in women with moderate facial photodamage. Each product was applied once daily to the designated half side of the face. Subjects were evaluated at baseline and after four and eight weeks of treatment using a 0-9 scale for photoaging parameters. The results showed that, after eight weeks, the retinol moisturizer was significantly more efficacious than the vehicle in improving lines and wrinkles, pigmentation, elasticity, firmness and overall photodamage. Many of these differences were significant at week 4, with a progressive improvement to week 8. This study demonstrates that a formulation containing stabilized retinol is safe and effective to ameliorate the appearance of photoaged skin.