Color purple. Free radicals are molecules with unpaired electrons that occur when the skin is exposed to UV rays or environmental pollution (carbon dioxide, cigarette smoke). These molecules trigger a reaction that damages the cellular structure of the skin. Antioxidants are the best way to neutralize free radicals. Familiar sources of antioxidants are berries, black beans and bright green leaves, but no more. To integrate antioxidants to your diet, can guide you through the color purple: cabbage, blueberries, raspberries, currants, pomegranate, purple sweet potato, red grapes … A plus: these foods stimulate the formation of collagen and elastin.