A method is provided for identifying a material having an efficacy for reducing color contrast between a hyperpigmented skin lesion and skin surrounding the hyperpigmented skin lesion without directly affecting melanocytes or melanogenesis. The method includes the steps of applying a composition containing a material to be tested to the hyperpigmented skin lesion； and after an interval of time, observing whether the composition has effected at least one of inhibiting proliferation of keratinocytes, stimulating differentiation of keratinocytes, and improving compressive deformation of dermal papillae, in a basal layer of epidermis in the hyperpigmented lesion of skin.
