Efficacy Evaluation of Whitening Cosmetics

Abstract

Purpose: To investigate the methods for evaluating whitening efficacy of four commercially available skin lightening cosmetics. Methods: The efficacy was taken on human. Select 28 female volunteers between 25 and 45 years old for each group, and use the cosmetics on the inner side of the crank arm for 8 weeks continuously. We evaluated whitening efficacy through measuring the MI, L*and ITA° value of skin before using the cosmetics and after using the cosmetics 1 week, 2 weeks, 4 weeks and 8 weeks later. Results: The MI, L*and ITA° of skin were significantly different (p<.05) before and after. Conclusion: Statistical analysis on the MI, L*and ITA° of skin can show the lightening effect of cosmetics directly, thus the method can be used to verify the lightening effect of cosmetics.