It is not known, however, which components of the Mediterranean diet act protectively in the organism. It is suggested that certain components of the diet may importantly affect oxidative stress (7) and thereby also occurrence of cardiovascular (8) and tumor diseases (9). There are also very interesting data on the relation between regional dietary habits and diet composition, and the occurrence of cardiovascular diseases. From this point of view Mediterranean region seems to be exemplary. Low incidence of cardiovascular diseases was demonstrated here already in 50´s in spite of relatively high fat intake, whose major source was, however, olive oil rich in monounsaturated fatty acids and antioxidants such as polyphenolic compounds 12(10). Mediterranean diet was proved also in controlled studies to have marked protective effects on development of cardiovascular diseases (11, 12), but also total mortality (6) probably by action of antioxidant substances increasing total antioxidant capacity (13). The role of dietary factors on total antioxidant status was described in numerous studies, which showed marked increase of antioxidant potential after administration of vitamin A (14), vitamin C (15), tomatoes or tomato products containing high amounts of antioxidative terpen lycopene or lycopene together with olive oil (16).