Tea - The Wonder Drug

Tea – The wonder drug

The Chinese have known the medicinal benefits of green tea for more than 4,000 years. Modern scientific research is revealing hard evidence regarding the health benefits associated with drinking green tea. A 1994 study by the National Cancer Institute indicated that drinking green tea reduced the risk of esophageal cancer in Chinese men and women by nearly sixty percent. Purdue research has shown evidence that a compound in green tea inhibits the growth of cancer cells. There is also research indicating that drinking green tea lowers total cholesterol levels, as well as improving the ratio of good (HDL) cholesterol to bad (LDL) cholesterol.

Recent medical studies declare tea to be a potential heart tonic, cancer blocker, fat buster, immune stimulant, arthritis soother, virus fighter and cholesterol detoxifier. A Hong Kong study suggests that the theaflavins in black tea may be equally as effective as the catechins in green tea. Prevention magazine reports that one cup of black or green tea has more antioxidant power than a serving of broccoli, carrots, or spinach. And on the horizon, white tea may be more effective than green tea.

Black, oolong, and green teas are all made from leaves of the same plant, the Camellia sinensis plant. The difference between them is the level of oxidation the tea leaves experience during their processing. Black and oolong teas are prepared by fermenting the leaves, which causes an oxidation process. The longer tea leaves experience oxidation, the darker they become.

Green tea leaves are steamed, which prevents the powerful EGCG antioxidant compound from being oxidized. The fermentation process for the black and oolong teas results in the EGCG being converted into other compounds that are not as effective in preventing and fighting various diseases.

Newer research suggests oxidation levels probably have little influence over the amount of heart-healthy flavonoids different teas contain, although there may be some variation. A recent animal study suggests both green and black tea may produce similar improvements in blood vessel health.

The only negative side effect reported from drinking tea is insomnia due to the fact that it contains caffeine. Tea prevents iron from being absorbed, so caution should be taken with children and anyone who is prone to anemia. The caffeine content of tea is one third to one quarter the amount of caffeine in an equivalent volume of coffee. Decaffeinating tea causes only a slight decrease in its antioxidant properties. Herbal teas do not have the antioxidants found in the Camillia sinensis teas. Bottles teas and instant teas have few antioxidants.

For best results, steep tea leaves or bags in hot water 3 to 5 minutes to thoroughly release antioxidants. Tea made from loose leaves has more antioxidants than tea bags, which tend to have lower-quality, powdered leaves. A Dutch study concluded that adding milk to tea does not block absorption of antioxidants. Recommendations for how much tea to drink varies from two to ten cups per day. An average 150-pound person would have to drink at least two 5-ounce cups of green or black tea daily to obtain significant benefits.

What makes green tea so special?

What sets green tea apart lies in the fact that it is rich in catechin polyphenols, especially epigallocatechin gallate (EGCG). EGCG is a powerful anti-oxidant which both inhibits the growth of cancer cells and kills them without harming healthy tissue. It has also been effective in lowering LDL cholesterol levels, and inhibiting the abnormal formation of blood clots. The anti-clotting benefit takes on added importance when you consider that thrombosis (the formation of abnormal blood clots) is the leading cause of heart attacks and stroke.

For many years the "French Paradox" puzzles researchers. Despite smoking and consuming a diet rich in fat, the French have a lower incidence of heart disease than Americans. The answer was found to lie in red wine, which contains resveratrol, a polyphenol that limits the negative effects of smoking and a fatty diet. A University of Kansas study in 1997 determined that EGCG is twice as powerful as resveratrol. This may explain the low rate of heart disease among Japanese men, even though almost seventy-five percent are smokers.

The Many Benefits of Drinking Tea

Research in the US, Taiwan and Japan showed mice which were fed oolong tea displayed fewer signs of aging than mice that were fed water. Perhaps drinking tea will decrease those wrinkles, age spots and other signs of growing old. Stay tuned for future investigations.

The antioxidants in green tea, which are so beneficial in protecting against heart disease and cancer, now shows promise in fighting allergies. Prevention magazine reported Japanese research that found the antioxidants in green tea block the biochemical process involved in producing an allergic response

The Journal of Nutrition reported evidence that consumption of the catechins in green tea is chondroprotective and may benefit the arthritis patient by reducing inflammation and slowing cartilage breakdown. An anti-inflammatory compound, TF2, in black tea is a cox-2 inhibitor. An action similar to the drug, Celebrex.

An article in the Archives of Internal Medicine compared Chinese men and women who regularly drank black, green, or oolong tea for more than 10 years with non-habitual tea drinkers. Those who drank tea on a regular basis had higher bone mineral densities, even after exercise and calcium-which strengthen bones-were taken into account.

Studies report strong evidence that both green and black tea can fight cancer. Green tea may hold a slight edge. One study showed that both teas kept healthy cells from turning malignant after exposure to cancer-causing compounds.

The powerful antioxidant, EGCG, inhibits an enzyme that cancer cells need to grow. If the cancer cells can’t grow big enough to divide, they self-destruct. It takes about 4 cups of green tea a day to get the blood levels of EGCG that inhibited cancer in the study, which reported these findings.

Vegetarian Times reported on a Maryland study, in which test subjects ate low-fat, low-calorie prepared meals and drink five cups of caffeinated tea or caffeinated and non-caffeinated placebos that mimicked the look of tea. Levels of low-density lipoprotein (LDL) cholesterol dropped 10 percent among the test subjects who drank tea.

Drinking black tea may lower the risk of heart disease because it prevents blood from clotting. Research participants who drank black tea on a regular basis had lower levels of the blood protein associated with coagulation. Studies in the Netherlands and US report significantly decreased risk in patients drinking tea.

A Chinese proverb says, “Better to be deprived of food for three days than tea for one.” A Boston hospital study reported that out of 1,900 heart-attack patients, those who drank two or more cups a day reduced their risks of dying over the next 3.8 years by 44 percent.

Trying to lose weight? Reach for a cup of green tea instead of a diet beverage. An American Journal of Clinical Nutrition investigation compared placebo and caffeine to green tea extract. The green tea extract produced a significant 4% increase in 24-hour energy expenditure. If you consume 2,000 calories per day a 4% increase in energy expenditure would translate roughly into an 80-calorie daily difference. Over a year, this could result in 89 pounds of weight loss.

Research suggests that the flavonoids in green tea may change how the body uses the hormone called norepinephrine, which affects the rate calories are burned.

Plus: Canadian researchers blocked cavities in mice by replacing their water with tea. Indian eye researchers have retarded cataracts in rats by feeding the animals tea extract. Israeli scientists blocked Parkinson's-like brain damage in mice by giving them green tea extract or pure EGCG.

The Bottom line

Each day you should drink three to six 8-ounce cups of tea. It can be black or green, hot or iced, decaf or not. Tea brewed from leaves is the most effective.