Food By Franz

History-Focus on Tea
Posted on 01/28/2009 04:57 pm by manx | Edit

A Wealth of Antioxidants

In Traditional Chinese Medicine, tea is considered a “grease cutter” that prevents harm from fatty foods, according to Efrem Korngold, O.M.D., a practitioner of Chinese medicine in San Francisco, and coauthor (with Harriet Beinfield, L.Ac.) of Between Heaven and Earth: A Guide to Chinese Medicine (Ballantine Books, 1992).

Japanese researchers wondered if this traditional belief could be scientifically verified. In the 1980s, they found potent antioxidant compounds in tea, notably epigallocatechin-3-gallate (EGCG). Antioxidants help prevent and repair the cell damage that can lead to heart disease and many cancers. Since then, dozens of additional studies have shown tea reduces risk of these diseases and helps treat them, thus validating Traditional Chinese Medicine’s claim.

Tea – White, Green and Black
The oxidation process that turns white and green teas into oolong and black teas destroys some of their EGCG. Black teas still contain significant amounts of antioxidants, which is why they reduce risk of heart disease and stroke. Alas, black teas have not shown much ability to reduce cancer risk. For cancer prevention, green tea is the way to go because it retains the most EGCG. White tea is promising too, although more studies are needed. As the least processed tea, it contains the most cancer-fighting polyphenols.

Tea Reduces Risk of Heart Disease

In the West, tea began its transformation from beverage into health food in 1993, when Dutch researchers published a study in the prestigious British medical journal Lancet on the effects of dietary antioxidants on risk of heart attack among residents of Zutphen, a city in the Netherlands. Men who consumed the most fruits and vegetables had the lowest heart attack risk. But tea also was protective, a finding that surprised Western scientists and sent them scurrying to the earlier Japanese research on ECGC. Since then, many studies have shown tea—both black and green—helps prevent heart disease and the most common type of stroke. Another group of Dutch researchers followed 4,807 men for five years. Compared with those who drank no tea, men who drank one or two cups a day had 43 percent fewer heart attacks—and 70 percent fewer heart attack deaths. Similar studies by Harvard and Saudi Arabian scientists also show fewer heart attacks and heart attack deaths in regular tea drinkers. And a Dutch study shows tea also reduces risk of stroke.

If tea really helps the heart, it should exhibit a “dose-response” effect—as tea consumption increases, heart disease risk should decline. That is the case. In the Harvard study, moderate tea drinkers were 31 percent less likely to suffer heart attack. The figure for heavy tea drinkers was 39 percent. The Saudi study also showed a dose-response effect. How do the antioxidants in tea reduce risk of heart attack and stroke? Several ways: They reduce cholesterol. They improve arterial function. And they slow the buildup of fatty, cholesterol-rich deposits on artery walls (atherosclerosis) that can lead to heart attacks and strokes.

Note: If you drink tea for heart benefits, don’t add milk. A German study suggests milk somehow neutralizes ECGC, counteracting tea’s heart-helping actions.

Green Tea Reduces Risk of All Major Cancers
An occasional report shows no cancer-protective benefits for green tea, but these few negative findings are vastly outnumbered by dozens of studies that show increasing green tea consumption decreases risk of all major cancers, including breast, ovarian, cervical, lung, stomach, prostate, colorectal, esophageal, pancreatic and malignant melanoma.
Green tea shows a clear “dose-response” effect for cancer prevention. Consider breast cancer. Australian researchers categorized green tea consumption in 2,018 Chinese women as low, moderate or high. Low tea intake reduced breast cancer risk 13 percent; moderate, 32 percent; high, 41 percent. A study at the University of Southern California showed a similar dose-response effect for reducing breast cancer risk.

This excerpt was taken from an online newsletter from The Herb Companion – Great site!