Abstract: The present invention relates to the use of a composition comprising an oil with a high content of essential fatty acids of &ohgr;3 and &ohgr;6 type, preferably blackcurrant seed oil, and at least one compound selected from &bgr;-carotene, lycopene, tocopherol and its derivatives, tocotrienols and their derivatives, ascorbic acid and nicotinamide, as a nutritional supplement intended for preventing and/or combating the harmful effects of xenobiotics on the skin, in particular on the skin's immune system.