Abstract: A cosmetic or pharmaceutical composition containing a synergistically active oxidation inhibiting system consisting of a combination of a ginkgo extract and at least one polyphenol compound. For example, the ginkgo extract may be a hexane extract of ginkgo leaves and the polyphenol compound may be a flavonoid. Said composition may be used to prevent and treat cell damage on the skin, scalp or mucosae by free radicals induced especially by atmospheric pollutants and/or ultraviolet radiation, and/or for controlling the phenomenon of accelerated skin ageing.