But often, free radical-induced changes lead to haywire changes in cellular function and reproduction, including the abnormal and uncontrolled growth of cancer cells. However, the same destructive power that renders free radicals so dangerous to human cells can be harnessed to protect cells from infectious invaders. Directed against harmful microorganisms, free radicals tear these diminutive miscreants to pieces. But here, too, when an excessive number of free radicals collect, these processes can go terribly wrong, destroying healthy cells and disrupting metabolism. Fortunately for our cell membranes and DNA, the body is equipped with potent defenses that can defuse the explosive threat of free radicals.
Antioxidant enzymes convert free radicals to more neutral, benign forms.
Food-derived antioxidants can neutralize free radicals by linking up with them. Even under the best of circumstances, the antioxidant enzymes can only partly stymie free radicals. To take up the slack, nutrients provide us with a variety of antioxidants that scavenge loose free radicals, capturing their excess electrons and preventing them from causing serious damage. Most of these antioxidant nutrients are found in or are derived from vegetarian foods, particularly leafy greens and red-pigmented fruits and vegetables. Aside from linking directly with free radicals, these nutrients also further the activity of antioxidant enzymes.