Wednesday, August 17, 2005

Food and Health - I [Green Tea and Cancer]

Green Tea and Cancer

Studies have shown that green tea affords protection in animals against cancers caused by polycyclic aromatic hydrocarbons, standard combustion products of automobiles and airplanes, formed and released in the atmosphere during the incomplete burning of coal, oil and gas, garbage, or other organic substances (e.g., in wild fires).

Beliveau R, Gingras D. Green tea: prevention and treatment of cancer by nutraceuticals. Lancet 2004;364:1021-2. doi: 10.1016/S0140-6736(04)17076-1

Park OJ, Surh YJ. Chemopreventive potential of epigallocatechin gallate and genistein: evidence from epidemiological and laboratory studies. Toxicology Letters. 2004;150:43-56. doi: 10.1016/j.toxlet.2003.06.001

Information on sources and toxic effects of polycyclic aromatic hydrocarbons: http://www.atsdr.cdc.gov/tfacts69.html.

Technical Point: Green tea contains a substance called epigallocatechin gallate, a member of the class of plant phytochemicals called polyphenols, that may mediate green tea's cancer-protecting effect by indirectly inhibiting the transcription of a gene, aryl hydrocarbon, known to mediate the toxic effects of numerous environmental contaminants, including the cancer-producing polycyclic aromatics hydrocarbons.

Palermo CM, Westlake CA, Gasiewicz TA. Epigallocatechin gallate inhibits aryl hydrocarbon receptor gene transcription through an indirect mechanism involving binding to a 90 kDa heat shock protein. Biochemistry 2005;44:5041-52. doi: 10.1021/bio47433p

For more on green tea, plus red wine, read:

The Elixir of Life: Green Tea or Red Wine?, by William H. Baarschers, SKEPTICAL INQUIRER Volume 29, Issue 5, September/October, pp 30-33.

The article identifies the author as:

“William H. Baaschers is a professor emeritus of chemistry at
Lakehead University in Thunder Bay, Ontario. His research
interests have included the chemistry of medicinal plants, synthetic chemistry, environmental science, and industrial toxicology. He is currently an advisor to the university’s Resource Centre for Occupational Health and Safety. He is the author of Eco-Facts and Eco-Fiction: Understanding the Environmental Debate (Rutledge, 1996).”

Future blog-entries: More on polyphenols; more on doi’s.

Questions: Which cancers protected against? How much green tea required, and for how long?

0 Comments:

Post a Comment

Links to this post:

Create a Link

<< Home