Romain De Dormael1, Philippe Bastien1, Peggy Sextius1,2,3,4,5, Audrey Gueniche1,2,3,4,5, Daniel Ye1,2,3,4,5, Christian Tran1,2,3,4,5, Véronique Chevalier1,2,3,4,5, Charles Gomes1,2,3,4,5, Luc Souverain1,2,3,4,5, Caroline Tricaud1,2,3,4,5. 1. Drs. de Dormael and Bastien contributed equally to this article. 2. Drs. de Dormael, Bastien, Sextius, Gueniche, Tran, Gomes. 3. Mr. Souverain are with L'Oréal Research and Innovation in Aulnay sous Bois, France. 4. Dr. Ye is with L'Oréal Research and Innovation in Shanghai, China. 5. Ms. Chevalier and Ms. Tricaud are with L'Oréal Research and Innovation in Chevilly-Larue, France.
Abstract
Background: Repeated nonextreme sun exposures induce skin pigmentation by increasing melanin production and by oxidizing preexisting melanin and melanin precursors. This leads to skin disorders and skin color heterogeneity such as hyperpigmented spots. Objective: We assessed 31 randomized, controlled clinical trials to determine the potential of vitamin C to limit ultraviolet (UV) daylight-induced pigmentation, considering dose response and different skin type populations (Caucasian and Chinese). Materials and Methods: Thirty-one intraindividual, randomized, controlled clinical trials involving Caucasian and Chinese subjects (15-35 healthy male or female volunteers per study, 741 total volunteers) 18 to 50 years of age with Phototype III and individual typology angle (ITA) value between 28 and 49 degrees were analyzed. The 31 studies assessed the potential of vitamin C (formulated with the copolymer Styrène-Anhydride Maléique [SMA]) to decrease pigmentation induced by UV daylight exposure. Results were combined using a Bayesian meta-analysis to provide probabilistic evidence of the effects of vitamin C by dose and population. Results: Vitamin C was effective in reducing pigmentation induced by UV daylight-simulated expositions (4 days at 0.75 Individual Minimal Erythemal Dose [MEDi]) in a dose-dependent manner. During the depigmentation phase, no additive value was provided by the vitamin C, suggesting that the lightening properties described in the literature for vitamin C correspond to an antipigmenting quality rather than a depigmenting effect. Conclusion: Vitamin C is a valuable and safe dermocosmetic antipigmenting compound with a strong effect at 10% possibly useful in preventing signs of photoaging.
Background: Repeated nonextreme sun exposures induce skin pigmentation by increasing melanin production and by oxidizing preexisting melanin and melanin precursors. This leads to skin disorders and skin color heterogeneity such as hyperpigmented spots. Objective: We assessed 31 randomized, controlled clinical trials to determine the potential of vitamin C to limit ultraviolet (UV) daylight-induced pigmentation, considering dose response and different skin type populations (Caucasian and Chinese). Materials and Methods: Thirty-one intraindividual, randomized, controlled clinical trials involving Caucasian and Chinese subjects (15-35 healthy male or female volunteers per study, 741 total volunteers) 18 to 50 years of age with Phototype III and individual typology angle (ITA) value between 28 and 49 degrees were analyzed. The 31 studies assessed the potential of vitamin C (formulated with the copolymer Styrène-Anhydride Maléique [SMA]) to decrease pigmentation induced by UV daylight exposure. Results were combined using a Bayesian meta-analysis to provide probabilistic evidence of the effects of vitamin C by dose and population. Results:Vitamin C was effective in reducing pigmentation induced by UV daylight-simulated expositions (4 days at 0.75 Individual Minimal Erythemal Dose [MEDi]) in a dose-dependent manner. During the depigmentation phase, no additive value was provided by the vitamin C, suggesting that the lightening properties described in the literature for vitamin C correspond to an antipigmenting quality rather than a depigmenting effect. Conclusion:Vitamin C is a valuable and safe dermocosmetic antipigmenting compound with a strong effect at 10% possibly useful in preventing signs of photoaging.
Entities:
Keywords:
Antipigmentation; Bayesian; topical; vitamin C