THE CONTEXT
Vitamin E is a major lipid-soluble antioxidant in cell membranes and plasma lipoproteins.
Chain-breaking antioxidant action
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Vitamin E traps free radicals by reacting with lipid peroxide radicals generated during peroxidation of polyunsaturated fatty acids.
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The resulting tocopheroxyl radical is relatively unreactive and ultimately forms nonradical compounds.
Regeneration and subsequent products
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Vitamin C from plasma commonly reduces the tocopheroxyl radical back to tocopherol.
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The resulting stable monodehydroascorbate radical undergoes enzymic or nonenzymic reactions to yield ascorbate and dehydroascorbate; neither product is a radical.