Antioxidants are substances, found in foods, which inhibit oxidation in the body's cells (oxidation is a chemical reaction that produces free radicals; they are molecules that damage DNA). Think of apple slices turning brown. Exposure to air turns them brown (oxidation). Adding an antioxidant, such as lemon prevents the oxidation. Inside the body, damage from free radicals can be more harmful. Free radicals may play a role in cancer, heart disease, and other diseases.
Examples of antioxidants include vitamins A, C, and E and the mineral selenium. Foods rich in antioxidants include berries, red grapes, kale, broccoli, and tea.
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