Abstract: The present invention relates to a composition in the form of a nano- or micro-emulsion, comprising: (a) at least one oil; (b) at least one nonionic surfactant with an HLB value of from 8.0 to 14.0, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13.0; (c) at least one ceramide compound; (d) at least one compound selected from Vitamin B3 and derivatives thereof; and (e) water. The composition according to the present invention can be used as a cosmetic composition and can enhance or improve the penetration of a ceramide compound into a keratin substance such as the skin.