More Benefits of Tea
The caffeine and theophylline in tea could excite the heart, speed up blood flow, increase filterings of kidney pellets, thereby having a diuresis capacity. In addition, they also have antibacterial and antidiarrhea functions. Caffeine also stimulates and excites the central nervous system. To have a couple of cups of tea after drinking liquor could guard against being drunk.
Here are the most recent studies on caffeine: "...there has been lots of surprisingly good news in general about caffeine and coffee. You would naturally assume that an addictive drug like caffeine--the most widely consumed psychoactive drug on the planet--must surely be bad for you, and initial studies suggested it might lead to bladder cancer, high blood pressure and other ills. More recent research has not only refuted most of those claims but also come up with some significant benefits. Caffeine appears to have some protective effect against liver damage, Parkinson's disease, diabetes, Alzheimer's, gallstones, depression and maybe even some forms of cancer. The only proven medical downside appears to be a temporary elevation in blood pressure, which is a problem only if you already suffer from hypertension. Some studies have also suggested a higher risk of miscarriage in pregnant women and of benign breast cysts, but those results are highly controversial...While most of the findings about the effects of caffeine remain open to further testing, caffeine's boosting your brainpower has been proved beyond any reasonable doubt...” (see "Measuring IQ Points by the Cupful," Time Magazine ﹝23 January 2006﹞, pp. 40-41.)
Quercetin, a flavonoid found in black and green tea protects LDL ("bad") cholesterol against oxidation. Oxidation of LDL is thought to cause or accelerate atherosclerosis. Several studies have found that eating foods high in quercetin lowers the risk of heart disease. A study by Boston University School of Medicine has shown that drinking 4 cups of black tea daily improves 50% impaired blood vessel functioning in heart patients. Green tea has been shown to lower total cholesterol levels and to improve the cholesterol profile (decreasing LDL cholesterol and increasing HDL cholesterol). However, not all trials have found that green tea intake lowers lipid levels.
Vitamins C and P, as well as tannic acid in tea strengthen blood vessel toughness and elasticity, lower blood cholesterol, prevent accumulation of fats in the liver, and check arteriosclerosis. These compounds also help the human body to adapt to the lack of oxygen in high altitude, to alleviate shortness of breath and other breathing ailments.
Tannic acid can treat enteritis and dysentery; may cause precipitation of nicotine and let it drain through urine. For this reason, smokers should drink more tea. Tannic acid, however, is a possible cause of oesophagal cancer.
Silicic acid in tea may cause leucocytosis, strengthening the disease-resistant ability of human body. It may also cause the tuberculosis spots to form scars, assisting the curing process of tuberculosis.
Trace elements of fluoridate in green tea as well as black tea (oolong tea contains higher amount) may reduce the risk of dental cares. An experiment of 20 human volunteers rinsing with an extract of oolong tea leaves before bed each night for four days had significantly less plaque formation, but similar amounts of plaque-causing bacteria compared to those with no treatment.
A study by Case Western Reserve University has shown that by drinking 4 cups of green tea daily it would reduce the development of arthritis in rats by 50%.
For more information on the benefits and other aspects of tea, see http://www.e2121.com/food_db/viewherb.php3?viewid=420&setlang=