For several years, researchers worldwide have speculated that antioxidant vitamins may protect healthy people or those with low reserves of natural antioxidant compounds against cardiovascular diseases, cancer, and other conditions. Yet definite conclusions have been elusive because no reliable technique exists to measure free radical activity in the body or determine if vitamins counteract the damage.
But in the March 31 Proceedings of the National Academy of Sciences, researchers at the University of Pennsylvania Medical Center in Philadelphia, Pa, describe a new, noninvasive technique to measure free radical activity. They have identified an isoprostane called IPF2α-I as a stable, abundant by-product of arachidonic acid that free radicals oxidize in the body. The by-product is easily detected in the urine, they report.
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