CLA antioxidant or prooxidant?

The conjugated linoleic acid (CLA) is a term referred to a mixture of posit ional and geometrical isomers of linoteic acid with double conjugated bonds in carbon atoms 10 and 12 or 9 and 11 with ail of the possible cis and tra ns combinations. CLA is a naturally occurring substance in food. The major dietary sources of CLA are foods derived from ruminants, e.g. beet and chee se and its content increases when meats are processed. There is ample evide nce showing that free radicals and oxidation processes mediated by free rad icals play an important role in many pathological situations including canc er and atherosclerosis. Natural and synthetic antioxidants, tolerated by hu mans, are employed in order to avoid or treat these pathologies. In the pre sent paper, articles evaluating the antioxidant or prooxidant activity of C LA have been revised. Preliminary in vivo and in vitro studies suggested th e antioxidant role for CLA, however recent researches have not shown any ev idence related to it. New studies have to be carried out in order to get mo re information on the antioxidant and protective role of CLA in free radica l-related degenerative diseases.