Novel pharmaceutical/cosmetic compositions contain at least one biaromatic ligand activator of a PPAR.gamma. receptor, such biaromatic ligand having the structural formula (I): ##STR00001## and are well suited, inter alia, for regulating and/or restoring skin lipid metabolism, for treating a wide variety of dermatological afflictions, and for preventing and/or treating the signs of aging and/or dry skin.