The antioxidant role of vitamin C

Ascorbate has been demonstrated to be an effective antioxidant. It can act both directly, by reaction with aqueous peroxyl radicals, and indirectly, by restoring the antioxidant properties of fat-soluble vitamin E. The overall consequence of these antioxidant activities is the beneficial control of lipid peroxidation of cellular membranes including those surrounding as well as within intracellular organelles. Intracellular free radical attack on non-lipid nuclear material may also be diminished.

In addition to reviewing the chemical basis of the antioxidant function of vitamin C, this report will focus on the importance of vitamin C as an antioxidant component of plasma as well as the extracellular fluids surrounding the lung, lens and retina. The protection by vitamin C of phagocytic cells involved in the defense against pathogen invasion will also be discussed.

This review presents evidence which supports the importance of vitamin C as a component of the overall antioxidant protective mechanisms found in cells and tissues. The data are consistent and form a strong consensus for investigating the importance of the antioxidant function of vitamin C in the maintenance of human health.