The elderly population undergoes a series of physiological and sociological changes common to old age with a high probability of suffering degenerative illness and malnutrition. A dessert rich in phenolic compounds has been designed by using concentrated juices of grape, cherry, blackberry, blackcurrant and raspberry with the aim of it being used as a complementary food in adulthood. In the present study, we investigated the effect of the intake of this dessert (a jar of 200 g daily for a period of 2 weeks), with an antioxidant activity equivalent to ten servings of fruits and vegetables, on several markers of oxidative and antioxidant status in DNA and plasma in a group of elderly individuals. Non-smoking institutionalised elderly subjects were recruited from a pool of volunteers in an old-age home in Murcia (Spain). Twenty-two subjects (six men and sixteen women) participated in the study. The study was designed as a randomised intervention trial with a period of 2 weeks. At days 1 and 15, blood samples were collected to analyse total antioxidant capacity, biochemical parameters, antioxidant vitamins, LDL peroxidation, and DNA damage in peripheral blood lymphocytes. The conclusion of the present study is that a 2-week intervention with our dessert enriched with natural polyphenol compounds in elderly individuals does not give enough time to find changes in the antioxidant and oxidative status. Also, the view that the marked antioxidant ability of polyphenols in vitro does not translate to analogous effects in vivo was confirmed. Moreover, a highly oxidative stress status during ageing was confirmed, together with the need to perform follow-up nutritional studies to improve this situation.