The old saying, “You are what you eat” seems to have a direct application to skin health. In fact, many antioxidants from various foods are currently undergoing research for use in prevention and treatment of signs of skin aging and skin diseases. In some studies they have been used topically; in others, internally, but generally there is a short list of nutrients that have received the most attention.
Green tea may be one of the foods that has received the most attention from researchers interested in skin health. At first, research primarily focused on whether it could aid in the prevention of certain skin cancers, such as basal cell carcinomas. Green tea contains a class of plant antioxidants called “polyphenols,” which seem to play a powerful role in neutralizing the free radicals that can lead to skin aging. In a double-blind, placebo-controlled two year study conducted by Stanford University, subjects that were given 250 milligrams of green tea polyphenols twice per day began to show improvement of signs of sun damage and redness after six months. The placebo group, when evaluated by dermatologists who did not know which group they were evaluating, showed no improvement. There have been a small number of studies utilizing green tea topically, as well, with good results. 
Other antioxidants, like Vitamin C, have also seemed to perform well in trials on skin aging. A 2008 study in the United Kingdom found that diets high in Vitamin C led to comparatively fewer wrinkles and less skin dryness than diets that were low in Vitamin C. In addition, several studies, including one published in the June 2006 Journal of Cosmetic Dermatology, found evidence that topical Vitamin C increases the production of collagen in facial skin. This makes sense, considering that Vitamin C is necessary for the production of collagen in all connective tissue – not just the skin.
Food sources of these antioxidants include fruits and vegetables for both Vitamin C and polyphenols; and teas, cocoa, olive oil and many nuts and seeds for polyphenols. They are available topically, as well, in various creams and serums. And, of course, both Vitamin C and green tea are available in supplement form, which can be particularly useful for those who don’t want the inconvenience and caffeine of drinking several cups of green tea per day.