Www. Nlm. Nih. Gov. Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are molecules produced when your body breaks down food, or by environmental exposures like tobacco smoke and radiation. Free radicals can damage cells, and may play a role in heart disease, cancer andthese are antioxidants :beta-carotene, lutein, lycopene, selenium, vitamin a, vitamin c, vitamin e.