Tea in the News Again
It seems like studies touting the cancer-fighting benefits of tea are cropping up regularly. The latest-from a presentation at the recent annual meeting of the American Chemical Society-hails the anti-cancer properties of black tea.
A team of researchers led by Dr. Kuang Yu Chen of Rutgers University in New Brunswick, New Jersey believes they have found the specific chemical ingredient in black tea that provides its protective effect against a number of cancers. In a series of laboratory experiments, they were able to isolate a compound called TF-2 (theaflavin-3'-monogallate), one of a family of compounds called polyphenols that have long been studied for their anti-cancer properties.
Chen's team added TF-2 to both healthy cells and colorectal cancer cells in the lab. While the normal cells were unaffected, he reported, the cancer cells rapidly underwent a process called apoptosis-programmed cell death. To initiate this "cellular suicide," Chen believes that TF-2 specifically acts to suppress the activity of the Cox 2 gene. Earlier studies have suggested that the Cox 2 gene, when left unchecked, helps to trigger a process that eventually causes normal cells to turn into cancer cells.
Polyphenols other than TF-2 are found in a number of foods and drinks, including grape skins and green tea. However, Chen said that the polyphenols in those foods exhibit a less dramatic anti-cancer effect than the polyphenols found in black tea.
Chen cautioned that the results of their experiments are preliminary and need to be duplicated with further research. But he suggested that their findings could someday lead to modified natural supplements-such as grape skin with enhanced polyphenols-that might provide significant anti-cancer benefits.
SOURCE:
Annual Meeting of the American Chemical Society, August 29, 2001, Chicago, IL