US researchers have discovered that compounds called polyphenols that are present in black and green tea can block the cancer-causing effect of ultraviolet light. Dr Zigang Dong of the University of Minnesota and colleagues applied a tumor-promoting chemical to the shaved backs of mice and then exposed them to ultraviolet B light. The researchers then rubbed a solution containing polyphenols on one group of the mice, while another group was left untreated. Results showed that the polyphenol solution somehow blocks the process by which a normal cell turns into a cancerous cell. At present the exact mechanism behind the polyphenols anti-cancer abilities remains uncertain. Dong says that he and his team are in the “very early stages” of developing a polyphenol-based lotion to be added to sunscreens in the hope that it may help to prevent skin cancer in people who have spent too long basking in the sunshine.
SOURCE/REFERENCE: Reported by www.reutershealth.com on the 9th September 2003.
