Background/aims: Facial aging is accompanied by modifications in the tensile properties and contours of skin. In the present study we instrumentally assessed and compared the effect of either 0.04% retinol (ROL), 1% melibiose and 4% lactose (ME-L) and their association (ROL-ME-L) to increase the firmness and smoothness of facial skin. A 1 % salicylic acid (SA) emulsion served as a cosmetic product reference.
Methods: A total of 120 women were allocated to four randomized groups of 30 subjects, each group receiving one of the test products or a combination of test products. The tensile properties of facial skin were measured using the Cutometer® on seven occasions during the 12-week treatment and during a 4-week post-treatment phase. Fine lines and wrinkles were assessed on replicas by using image analysis after optical shadowing.
Results: Significant differences in efficacy and lingering activity were observed between products. SA brought the weakest beneficial effects. ROL and ME-L provided better efficacy on both the tensile properties and contours of skin. They differed slightly according the nature of the biometrological variables. The combination ROL-ME-L achieved similar or even better results than the best of its components for each given physical property of skin.
Conclusions: ROL, ME-L, and ROL-ME-L formulations improve physical properties of skin that are impaired by aging. Their activities are notably superior to those of a comparative SA formulation.
Keywords: facial skin; lactose; melibiose; retinol; skin tensile properties.