Plant extracts have been widely used as topical applications for wound healing, anti-aging and in disease treatments. Plants used for this purpose share a common character: They all produce antioxidant compounds. Green tea contains antioxidant compounds called polyphenols. Some laboratories have shown that topical treatment and oral consumption of green tea inhibits the start of ultraviolet radiation-induced skin tumors in animals. According to the authors, Green tea may “have the potential when used in conjunction with traditional sunscreens to further protect the skin against the adverse effects of ultraviolet radiation.”
Nabiha Yusuf, Cynthia Irby, Santosh K. Katiyar, Craig A. Elmets (2007). Photoprotective effects of green tea polyphenols.
Photodermatology, Photoimmunology & Photomedicine 23 (1), 48–56.