Contrasting actions of various antioxidants on hyperlipidemia: A review and new concepts

Hyperlipidemia can lead to disorders that result in the onset of various diseases, including cardiovascular diseases
which are the leading cause of death in many industrialized countries. Antioxidants are recommended in the
treatment of various diseases, particularly atherosclerosis. However, the results of the studies are inconclusive and
do not provide strong evidence that antioxidants have a substantial effect on disease. From the results of the studies
presented in this paper it might be concluded that although antioxidants might be beneficial in patients with
atherosclerosis or other cardiovascular diseases, however, single or even combination of a few antioxidants are
not reliable agents for this purpose. This might be due to the complexity of free radicals which are produced and
work as a continuous chain. It is known that after scavenging electron, if an antioxidant is not restored by the
following antioxidant in the chain, it usually changes to a pro-oxidant. In this situation, the final effect of such
supplementation would be no or a damaging effect. In this review study, other than presenting and discussing the
studied antioxidants on hyperlipidemia and cardiovascular diseases, the possible reasons for the opposing actions
of different antioxidants are discussed in detail.