Green Tea: Health Articles
Database - Green tea research has shown it has an effect on variety of health conditions. The ability to lower blood sugar, chelate iron and control the production of nitric oxide are all especially
important. This ancient beverage seems custom-made to protect health and delay aging. To find how green tea benefits different organs and conditions click a specific topic from our article database below:
Research shows that green tea lowers total cholesterol and raises HDL ("good") cholesterol in both animals and people. One population-based clinical study found that men who drink green tea are more likely to have lower total cholesterol than those who do not drink green tea. Results from one animal study suggest that polyphenols in green tea may block the intestinal absorption of cholesterol and promote its excretion from the body. In another small study of male smokers, researchers found that green tea significantly reduced blood levels of harmful LDL cholesterol.
Cholesterol Lowering Properties of Green Tea - Animal Study II
Green tea may also lower intestinal fat absorption. One animal study found that rats fed a diet containing a significant amount of catechin had a higher excretion of fat in the feces compared to the control group on a polyphenol-free diet. If this holds for humans who take the green tea extract, then it's good weight-loss and cardiovascular news. Supplementation with antioxidants is important in part because by protecting cholesterol from oxidation, antioxidants help protect against atherosclerosis. In an animal study comparing the effectiveness of various antioxidants in preventing the oxidation of VDL and LDL cholesterol, vitamin E, genistein (phytoestrogen found chiefly in soy products) and green tea were found to be effective antioxidants, with genistein being particularly effective (oxidation lag time of 49% on the high-genistein diet), but green tea also exerting considerable activity (lag time of 33%). It would be interesting to see the results of combined genistein and green tea supplementation, particularly in humans. On the other hand, it could be argued that this is precisely the case of the Japanese diet. Japan enjoys the longest life expectancy in the world, and the lowest cardiovascular mortality for men, in spite of heavy smoking.
Cholesterol Lowering Properties of Green Tea - Animal Study
Research shows that green tea lowers total cholesterol and raises HDL ("good") cholesterol in both animals and people. When rats were fed 2.5% green tea leaves in their diet the experimental group showed a drop in total cholesterol, low-density cholesterol, & triglycerides. The body weight of green tea-fed rats was 10 to 18% lower than that of rats not consuming green tea. In addition, the activity of antioxidant enzymes superoxide dismutase (SOD) and catalase, and of anti-carcinogenic phase-II enzyme glutathione S-transferase (GST), were significantly higher in the green tea group, as was the glutathione level in the liver. There was no liver or kidney toxicity. Thus, the study demonstrated combined cardiovascular and anticancer effects of green tea. Results from one animal study suggest that polyphenols in green tea may block the intestinal absorption of cholesterol and promote its excretion from the body.
Cholesterol Lowering Properties of Green Tea - Smokers Study
One population-based study found that men who drink green tea are more likely to have lower total cholesterol than those who do not drink green tea. In another small study of male smokers, researchers found that green tea significantly reduced blood levels of harmful LDL cholesterol.
Cholesterol Lowering Properties of Green Tea - Vanderbilt U.
In a double-blind, randomized, placebo controlled trial done by Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, 240 adults were given either theaflavin-enriched green tea extract in form of 375mg capsule daily or a placebo. After 12 weeks, patients in the tea extract group have significantly less low-density lipoprotein cholesterol (LDL-C) and total cholesterol (16.4% and 11.3% lower than baseline, p<0.01) then the placebo group. The author concluded that theaflavin-enriched green tea extract can be used together other dietary approaches to reduce LDL-C.
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