• Testimonials
• Company
  • Contact
• Buy Now
• Product
  • 10 Day Slim
  • Cheia Vida
  • Cheia Vida Slim
  • Cheia Cleanse
  • RevvNRG
  • Cheia Relief
• Home

Green Tea

"Better to be deprived of food for three days, than tea for one." (Ancient Chinese Proverb)

• Detoxifies the body
• May help neutralize allergens
• Supports healthy immune system response
• Helps sustain energy levels
• Boosts exercise endurance
• Supports a healthy circulatory system
• Spurs the use of fat as energy
• Green Tea catechins have enormous antioxidant activity
• Rich in health-promoting flavonoids (30% of dry weight)
• May improve the ratio of good (HDL) cholesterol to bad (LDL) cholesterol

Archeological evidence suggests that people consumed tea leaves steeped in boiling water as many as 500,000 years ago. Botanical evidence indicates that India and China were among the first countries to cultivate tea. Today, hundreds of millions of people drink tea around the world, and studies are now suggesting that Green Tea (Camellia sinesis) in particular has many health benefits.

Green Tea Catechins

The healthful properties of green tea are largely attributed to polyphenols, chemicals with potent antioxidant properties. In fact, the antioxidant effects of polyphenols appear to be greater than vitamin C. Emerging studies suggest that the polyphenols in green tea are important fighters of free radicals and promote healthy cell growth. The green tea catechins make up approximately 30% of the dry weight of green tea leaves.

Polyphenols contained in teas are classified as catechins. The four major catechins found in green tea leaves are;

• Epigallocatechin Gallate (EGCG)
• Epicatechin Gallate (ECG)
• Epigallocatechin (EGC)
• Epicatechin (EC).

The aforementioned are all polyphenolic substances, but EGCG is the most active and has attracted the most attention as a very powerful antioxidant. Besides encouraging normal cell growth, EGCG has been researched around the world for its ability to neutralize unhealthy cells without harming healthy tissue. It has also been shown to be effective in supporting enhanced blood flow to the extremities.

EGCG appears to be the most potent antioxidant of the green tea catechins, it also may have the greatest possible antioxidant activity. Research shows this highly potent antioxidant:

• Helps prevent the formation of B-amyloid, a protein whose accumulation is recognized as causing Alzheimer's (Basianetto S, Eur J Neurosci Jan 2006).
• Protects brain cells by chelating (removing) iron, which might otherwise produce destructive free radicals (Reznichenko L, J Neurochem, March 2006).
• Helps prevent oxidative stress-induced brain cell death by "talking" to brain cells' genes responsible for cell cycling and survival. Specifically, EGCG tells the genes in neurons to decrease production of caspase 3, an enzyme involved in initiating programmed cell death. (Park HJ, Life Sci Jan 2006; Levites Y. J Biol Chem, 2002)
• Promotes memory-related learning ability by protecting cells in the hippocampus, a part of the brain involved in spatial cognition and memory-related learning ability, from free radical damage (Haque AM, J Nutr April 2006).

Green tea catechins have also been found to regulate the synthesis of some hepatic phase II enzymes that are involved in the detoxification of some xenobiotics, including chemical carcinogens.

Green Teas many uses

Green tea drinkers appear to have lower risk for a wide range of diseases, from simple bacterial or viral infections to chronic degenerative.

Exercise Boost

The studies conducted by Biological Sciences Laboratories of Kao Corp. in Tochigi, Japan show that green tea extract can boost exercise capacity and support the research showing that stimulating the use of fatty acids can improve endurance.

It's thought that this might improve exercise performance by allowing the body to get energy from fat rather than carbohydrates during endurance activities.

Another recent study reached the conclusion that green tea extracts increase energy expenditure and fat oxidation in humans. These thermogenic effects were said to go beyond green tea's thermogenic caffeine effects and to be synergistic with them. Compared with placebo, 90 mg of EGCG and 50 mg of caffeine produced a significant 4% increase in 24-hour energy expenditure and a significant decrease in 24-hour respiratory quotient in healthy men. Supplementation with 50 mg of caffeine alone did not have significant thermogenic effects.

Green tea extract given to lab rats over a 10-week span increased the amount of time the animals could swim before becoming exhausted by as much as 24%.

Green tea's catechins appear to stimulate the use of fatty acids by liver and muscle cells. In muscle cells, the ability to burn more fat translates into a reduction in the rate at which glycogen, the form in which carbohydrates are stored for ready access in muscle, is used up, thus allowing for longer exercise times. Green tea's effect on muscle cells' ability to take in and burn fatty acids, speeding up fat breakdown, is also thought to be the reason why it helps weight loss.

The idea for the experiment came from the fact that skeletal muscles utilize carbohydrates, lipids (fats) and amino acids (protein) as energy sources, but the ratio in which they are used varies with the intensity and type of the exercise, and the level of the individual's fitness. During endurance exercise, the use of too much carbohydrate is undesirable because it triggers insulin secretion, which, in turn, both inhibits the burning of fatty acids and stimulates lactic acid production. (Lactic acid buildup is what causes that sore achy feeling in your muscles when you exercise.) Conversely, enhanced availability and utilization of free fatty acids reduces carbohydrate utilization, which in turn spares glycogen (the form in which carbohydrates are stored in muscle for quick use) and suppresses lactic acid production, resulting in an increase in endurance."

Drinking a single cup of green tea before exercise, however, will not be effective. One single, higher "dose" of green tea did nothing to improve lab rats' performance. The animals had to receive green tea daily, and endurance increased gradually over the 10 weeks of the study. To match the beneficial effect on test animals' endurance capacity seen in the experiments, the researchers estimate a 165-pound athlete would need to drink about 4 cups of green tea daily.

Weight loss

Studies suggest that green tea extract may boost metabolism and help burn fat. One study confirmed that the combination of green tea and caffeine improved weight loss and maintenance in overweight and moderately obese individuals.

In November, 1999, the American Journal of Clinical Nutrition published the results of a study at the University of Geneva in Switzerland. Researchers found that men who were given a combination of caffeine and green tea extract burned more calories than those given only caffeine or a placebo.

Green tea has thermogenic properties that cause carbohydrates to be released slowly, preventing sharp increases in blood-insulin levels. This promotes the burning of fat.

Green tea not only promotes fat loss, but specifically, the loss of visceral fat-fat that accumulates in the tissues lining the abdominal cavity and surrounding the intestines (viscera) and internal organs. Green tea contains three major components that promote fat loss: catechins, caffeine and theanine. Studies suggest that green tea compounds promote fat loss by inhibiting both gastric and pancreatic lipase, the enzymes that digest triglycerides, and fatty acid synthetase, the enzyme responsible for synthesizing fatty acids into the form in which they can be stored in the body's adipose (fat) cells.

In a study published in the January 2004 issue of In Vivo in which mice were fed diets containing 2% green tea powder for 16 weeks, visceral fat decreased by 76.8% in those receiving green tea compared to the control group. Green tea also decreased blood levels of triglycerides (the chemical form in which most fats exist in the body).

A human study, published in the January 2005 issue of the American Journal of Clinical Nutrition, confirms green tea's ability to not only reduce body fat, but to damage LDL cholesterol as well. After 12 weeks of drinking just one bottle of green tea each day, 38 normal-to-overweight men in Tokyo had a significantly lower body weight, BMI, waist circumference, body fat mass and amount of subcutaneous fat compared to men given a bottle of oolong tea each day.

After a 2-week diet run-in period, the men were divided into two groups, one of which drank a bottle of green tea containing 690 mg of catechins, while the other group drank a bottle of oolong tea containing 22 mg catechins.

Not only did the men drinking green tea lose weight and fat, but the amount of their LDL cholesterol damaged by free radicals also dropped significantly. Since atherosclerotic plaques develop when cholesterol circulating in the bloodstream is damaged or oxidized, green tea's ability to prevent these oxidation reactions may explain some of its protective effects against cardiovascular diseases.

Human Body

In Japanese studies, green tea consumption has been found to be an independent predictor for risk of coronary artery disease. In one study, those drinking 5 or more cups of green tea each day were found to be 16% less likely to suffer from coronary artery disease. The relationship was so significant researchers concluded, "The more green tea patients consume the less likely they are to have coronary artery disease."

An elevation in the amount of free radicals in the arteries is a key event in many forms of cardiovascular disease. The latest research shows that green tea catechins inhibit the enzymes involved in the production of free radicals in the endothelial lining of the arteries. The arterial endothelium is a one-cell thick lining that serves as the interface between the bloodstream and the wall of the artery where plaques can form. By protecting the endothelium from free radical damage, green tea catechins help prevent the development of cardiovascular disease.

The primary catechin in green tea, EGCG (epigallocatechin-3-gallate) confers such powerful protection that it can help prevent the death of heart muscle cells following ischemia/reperfusion injury. Ischemia is the medical term for a restriction in blood supply and therefore in oxygen and nutrients. When circulation is restored, oxidative damage occurs, and this is referred to as reperfusion injury. EGCG prevents heart muscle damage by blocking the activation of inflammation-related compounds (including NF-kappa-B and STAT-1) that play a critical role in promoting the oxidative damage that kills heart cells in reperfusion injury. Researchers believe EGCG can be used to help minimize damage in patients with acute coronary artery disease.

Research conducted by Dr. Anastasis Stephanou and his team at the UK's Institute of Child Health and published in the FASEB Journal, the journal of the Federation of Experimental Biology and the Journal of Cellular and Molecular Medicine has focused on EGCG's ability to block the action of the protein, STAT-1. Normally activated in cells after a heart attack or stroke, STAT-1 plays a major role in inducing cell death.

Not only does green tea minimize heart cell death after a heart attack or stroke, ECGC also appears to speed up heart cells' recovery from damage, allowing the tissues to recover more quickly and alleviating damage to organs. Dr. Stephanou, a molecular biologist, noted: "We're extremely encouraged by these findings and hope to implement them in the clinical setting to minimize cell death activation in patients with acute coronary heart disease."

EGCG has also been shown to protect brain cells by these same mechanisms and thus may help minimize the brain damage that occurs after a stroke. In one animal study, green tea was so effective in reducing the formation of free radicals in brain tissue that the researchers concluded, "Daily intake of green tea catechins efficiently protects the brain from irreversible damage due to cerebral ischemia, and consequent neurologic deficits."

Inhibits Atherosclerosis / Cholesterol

Green tea has been shown to effectively lower risk of atherosclerosis by lowering LDL cholesterol, triglycerides, lipid peroxides (free radicals that damage LDL cholesterol and other lipids or fats) and fibrinogen (a protein in the blood involved in the formation of blood clots), while improving the ratio of LDL (bad) to HDL (good) cholesterol. In animal studies in which green tea was given in human equivalent doses to hamsters, atherosclerosis was inhibited 26-63%. Depending on the total amount of green tea prescibed.

Research shows that green tea lowers total cholesterol and raises HDL ("good") cholesterol in both animals and people. 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. 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.

The inhibition of the oxidation of low-density lipoproteins is another possible anti-atherogenic mechanism. The green tea catechins may also have antithrombotic activity and may aid in lowering total cholesterol and LDL-cholesterol levels. The antithrombotic effect appears to be at the platelet level. These catechins have been found to inhibit ADP- and collagen-induced platelet aggregation in rats. Coagulation parameters were not affected. The mechanism of the possible cholesterol-lowering effect is unclear. It is thought that the green tea catechins may stimulate the secretion of bile salts and the fecal excretion of cholesterol.

Thins the Blood and Helps Prevent Blood Clots

Green tea catechins help thin the blood and prevent the formation of blood clots by preventing the formation of pro-inflammatory compounds derived from omega-6 fatty acids, which are found in meats and polyunsaturated vegetable oils such as corn, safflower and soy oil. These pro-inflammatory compounds-specifically, arachidonic acid from which the inflammatory cytokines thromboxane A2 and prostaglandin D2 are derived-cause platelets to clump together.

Lowers Blood Pressure and Helps Prevent Hypertension

A study published in the July 2004 issue of the Archives of Internal Medicine found that among persons consuming tea regularly for at least one year, the risk of developing high blood pressure was 46% lower among those who drank 1⁄2 cup to 2 1⁄2 cups per day, and 65% less among those consuming more than 2 1⁄2 cups per day. In another study, this one of rats bred not only have high blood pressure but also to be prone to strokes, those rats given green tea had significantly lower systolic and diastolic blood pressure compared to controls, who received plain water. The animals in this study, which was published in the January 2004 issue of the Journal of Nutrition, consumed the human equivalent of 1 liter (1.1 quarts or a little more than 4 cups) of green tea per day.

Inflammatory Bowel Disease (IBD)

Green tea may help reduce inflammation associated with Crohn's disease and ulcerative colitis, the two types of IBD. If green tea proves to be helpful for preventing colon cancer, this would be an added benefit for those with IBD because they are at risk for colon cancer.

Diabetes

Green tea has been used traditionally to control blood sugar in the body. Animal studies suggest that green tea may help prevent the development of type 1 diabetes and slow the progression once it has developed. People with type 1 diabetes produce little or no insulin, a hormone that converts glucose (sugar), starches, and other foods into energy needed for daily life. Green tea may help regulate glucose in the body.

Liver disease

Population-based studies have shown that men who drink more than 10 cups of green tea per day are less likely to develop disorders of the liver. Green tea also seems to protect the liver from the damaging effects of toxic substances such as alcohol. Animal studies have shown that green tea helps protect against the development of liver tumors in mice.

Improves Insulin Sensitivity in Type 2 Diabetes

Population studies suggest that green tea consumption may help prevent type 2 diabetes. A number of animal studies are beginning to explain why. New studies suggest that green tea may improve glucose tolerance and insulin sensitivity in individuals with diabetes. In one study, after receiving green tea for 12 weeks, diabetic rats had lower fasting blood levels of glucose, insulin, triglycerides and free fatty acids compared to controls, and the ability of their adiopcytes (fat cells) to respond to insulin and absorb blood sugar greatly increased.

In another study by the same research group, diabetic rats were separated into three groups and followed for 12 weeks. One group was given with standard rat chow and water (the control group), the second group received a high fructose diet and water (fructose group), and the third group got the same high fructose diet and green tea (green tea group). By the end of the study, the fructose group had high blood sugar, high insulin levels, and high blood pressure, while the animals receiving green tea along with a high fructose diet showed improvement in all three.

A study published in the August 2004 issue of BMC Pharmacology, in which oral glucose tolerance tests were given to healthy humans after they consumed green tea, showed that it increased the body's ability to utilize blood sugar.

Another interesting animal study compared the effects of a Western diet, a vegetarian diet and a Japanese diet, each with or without green tea. Blood sugar concentrations were highest in the animals on the Western diet followed by the Vegetarian diet with the Japanese diet producing the lowest blood sugars. When supplemented with green tea, blood sugar levels dropped in rats on all three diets, with those on the Japanese diet having not only the lowest blood sugars but also rating the best on other risk factors for type 2 diabetes. Rats on the Japanese diet that also were given green tea had the lowest triglycerides and cholesterol as well as the highest ratio of beneficial omega-3 fatty acids to potentially inflammatory omega-6 fatty acids. The researchers concluded that Japanese eating habits combined with drinking green tea might help prevent type 2 diabetes.

Protects against Kidney Disease

An animal study published in the January 2005 issue of Pharmacological Research suggests yet another beneficial effect of green tea consumption: the prevention of kidney dysfunction in persons who must take powerful immunosuppressant drugs, for example, after an organ transplant.

One such drug, cyclosporine A, while a very effective immunosuppressant, also markedly elevates the production of free radicals highly toxic to the kidneys. In this study, rats given green tea as their drinking water along with cyclosporine A produced far fewer damaging free radicals than rats given plain water. In addition, a number of other indicators of kidney function (serum creatinine, blood urea nitrogen, uric acid and urinary excretion of glucose) were significantly better in rats given green tea. Another animal study published in May 2004 in the Annals of Nutrition & Metabolism explains why. Diabetic rats given green tea catechins and then exposed to a kidney-damaging drug, streptozotocin, produced less than half the amount of superoxide radicals (a particularly damaging type of free radical) compared to diabetic rats on a catechin-free diet. As a result, a cellular waste product formed by free radical damage to fats, lipofuscin, was almost 200% higher in the diabetic rats who did not receive green tea catechins compared to those who did.

Builds Bone

Researchers at the University of Tokyo have shown drinking green tea may significantly increase bone mineral density.

Their study, presented at the International Osteoporosis Foundation World Congress on Osteoporosis, Toronto, Canada, June 5, 2006, included 655 women aged 60 years or older. Participants completed a questionnaire about their consumption of green tea, milk, cheese, yogurt, fish, vegetable, tofu, natto (a soy food), meat and coffee; smoking, alcohol consumption, physical activity and use of anti-osteoporosis bisphosphonate drugs like Fosamax.

For each dietary item, subjects were divided into two groups: 1) those who consumed the item five or more days per week, and 2) those who consumed the item fewer than five days per week. The researchers then measured the bone mineral density (BMD) of the women's lumbar spines, as well as blood markers for osteoporosis risk, including levels of calcium, phosphorus, parathyroid hormone, alkaline phosphatase, osteocalcin, and vitamin D.

Women who drank green tea 5 or more days per week had an average BMD significantly higher (0.808 grams of hydroxyapatite-form calcium per square centimeter) than those drinking green tea less than 5 days per week (0.738 grams per square centimeter).

Green tea drinkers' bone-density advantage persisted even after results were adjusted for age, body mass index, other dietary items, smoking, alcohol, physical activity and use of osteoporosis drugs.

The Tokyo team hypothesized the catechin flavonoids in green tea provided the benefits via estrogenic effects known to build bone strength and/or induce apoptosis ("suicide") in bone-destroying cells called osteoclasts. Both mechanisms are similar to the ways in which bisphosphonate drugs like Fosamax prevent bone loss. But while these potent drugs can provoke inflammatory eye disorders, abdominal pain, nausea, vomiting, dyspepsia and diarrhea, green tea is not only completely safe, but a delicious beverage that offers a legion of other health benefits.

Prevents Osteoporosis and Periodontal Diseases

Human BodyExcessive bone loss is a characteristic feature not only of osteoporosis but of periodontal disease. Green tea supports healthy bones and teeth both by protecting osteoblasts (the cells responsible for building bone) from destruction by free radicals, and by inhibiting the formation of osteoclasts (the cells that break down bone).

Another benefit of green tea consumption for those with periodontal disease: green tea short circuits the damaging effects of the bacteria most responsible for gum disease, Porphyromonas gingivalis. P. gingivalis causes gum damage by producing toxic byproducts such as phenylacetic acid and by stimulating the activity and production of enzymes called metalloproteinases (MMPs), which destroy both the mineral and organic constituents that make up the matrix of our bones. Epigallocatechin-3-gallate (EGCG) inhibits P. gingivalis' production of both phenylacetic acid and MMPs.

Green tea can even help prevent tooth decay! Just as its bacteria-destroying abilities can help prevent food poisoning, it can also kill the bacteria that causes dental plaque.

Protects the Liver from Alcohol and Other Harmful Chemicals

Alcohol metabolism results in the production of damaging free radicals that can overwhelm the liver's supply of antioxidants, resulting in liver injury. In a study published in the January 2004 issue of Alcohol in which rats were chronically intoxicated with alcohol for 4 weeks, green tea prevented damage to their livers.

Other animal research shows that epigallocatechin-3-gallate (EGCG) protects the liver against the free radicals generated when mice are exposed to carbon tetrachloride, a toxic chemical solvent. Without the protection afforded by EGCG, carbon tetrachloride exposure resulted in the production of numerous free radicals that destroyed a significant amount of the animals' liver cells. With EGCG, free radical production and liver injury was so greatly reduced that researchers suggested green tea should be used in the treatment of liver disease.

Unlike some herbs, green tea's protective effects do not appear to affect two of the liver enzymes most often responsible for detoxifying and eliminating drugs, cytochrome P-450 2D6 and 3A4. This suggests that green tea might be safely consumed when taking medications primarily dependent upon the CYP2D6 or CYP3A4 pathways of metabolism. Hopefully, future research studies will bear out this potential benefit.

On the other hand, one study found that Japanese green tea did increase the activity of the CYP1A1 enzyme. Researchers hypothesized that the increase in activity of this liver enzyme may be one of the ways in which green tea helps protect against cancers caused by various dietary carcinogens.

Protects Against Cognitive Decline, Alzheimer's Disease and Parkinson's Disease

Damage to brain cells in Parkinson's, Alzheimer's and other neurodegenerative diseases seems to result from the combination of a number of damaging factors including excessive inflammation and increased levels of iron, both of which lead to increased free radical production, exhaust the brain's supply of protective antioxidants and trigger the production of certain proteins, such as amyloid-beta, which promote apoptosis (cell suicide).

Green tea catechins, until recently thought to work simply as antioxidants, are now known to invoke a wide spectrum of neuroprotective cellular mechanisms. These include iron chelation, scavenging of free radicals, activation of survival genes and cell signaling pathways, and regulation of mitochondrial function. (The mitochondria are the energy production factories inside our cells. When they are not working properly, they generate many free radicals and little energy.) The end result is a significant lessening of damage to brain cells.

Iron accumulation in specific brain areas and free radical damage to brain cells are considered the major damaging factors responsible for a wide range of neurodegenerative disorders including both Parkinson's and Alzheimer's disease.

In the brain, epigallocatechin-3-gallate (EGCG) has been shown to act as an iron chelator, binding to and removing iron, thus preventing it from contributing to the production of free radicals. In addition to removing iron, EGCG also increases the activity of two major antioxidant enzymes, superoxide dismutase (SOD) and catalase, further helping to decrease free radical damage. Another active compound in green tea, epicatechin (EC), reduces the formation of a protein called amyloid-beta. Plaque-like deposits of amyloid-beta in the brain are a defining characteristic of Alzheimer's disease.

Animal studies conducted at the Douglas Hospital Research Centre, McGill University, Quebec, Canada, suggest that a daily cup or two of either black or green tea may reduce the risk of age-related degenerative brain disorders such as Alzheimer disease.

The researchers looked at the protective effects of two tea extracts and their main constituents, epigallocatechin gallate and epicatechin gallate, which are highly concentrated in green tea, on dying nerve cells. Both black and green tea extracts and catechins strongly blocked death of neurons (brain nerve cells) When researchers exposed cultured neurons to amyloid alone, its effects were so toxic that the brain cells died, but when the cell cultures received amyloid immediately followed by tea extracts and catechins, the neurons were rescued and survived.

Green tea polyphenols have also demonstrated the ability to affect cell signaling pathways, in particular the MAPK pathways, which are triggered by oxidative stress (free radicals), and themselves set in motion a series of chemical reactions so damaging that they can result in brain cell death. MAPK signaling pathways inside brain cells are thought to play a critical role in neurodegenerative diseases. Another important cell signaling pathway beneficially affected by EGCG, the PKC pathway, is also thought to play an essential role in the regulation of cell survival and programmed cell death.

Although no human studies on Alzheimer's disease have yet reported benefit from tea consumption, recent population studies have shown that simply consuming 2 or more cups of green tea daily reduces risk of cognitive decline and Parkinson's disease.

Green Tea Keeps Elders Mentally Sharp: Research Showing Multiple Ways

Green tea helps slow the age-related decline in brain function seen as declining memory, cognitive impairment, dementia and Alzheimer's, shows a human study published in the February 2006 issue of the American Journal of Clinical Nutrition.

Researchers at Japan's Tohoku University studied 1003 subjects over age 70, comparing their green tea intake and mental sharpness, using a Mini-Mental State Examination, a well-accepted standardized test for measuring cognitive function.

Drinking more than 2 cups (3.2 fluid ounces each)a day of green tea slashed odds of cognitive impairment in elderly Japanese men and women by 64%!

And at every level of cognitive impairment-from minimal to severe-those drinking the most green tea experienced significantly less mental decline than those drinking the least:

Compared with elderly Japanese who drank less than 3 cups a week, those drinking more than 2 cups a day had a 54% lower risk of age-related declines in memory, orientation, ability to follow commands and attention.

Those drinking 4 to 6 cups of green tea a week (1 cup a day) had a 38 lower risk of declines in brain function.

Inflammatory Effects

Green tea and its constituents have exhibited a variety of anti-inflammatory effects, raising hopes that they might be helpful in treating some forms of arthritis, dermatosis, gout and other inflammatory conditions. In an animal model of inflammatory polyarthritis with similarities to human rheumatoid arthritis, green tea polyphenols, in three experiments, significantly reduced the incidence of arthritis (33 to 50%), compared with controls (84 to 100%). Inflammatory cytokines, tumor necrosis factor and interferon-gamma and RA-specific immunoglobulin-G were all reduced in the animals given the green tea polyphenols.

Green Tea Fights the Flu

A cup of green tea may help prevent or lessen the duration of the flu. In a lab study, published in the November 2005 issue of Antiviral Research, EGCG dramatically inhibited influenza virus replication in cell culture in all the subtypes of influenza virus tested. EGCG appears to suppress viral RNA synthesis by altering the properties of the viral membrane.

AIDS Studies

(AIDSmeds.com) - A component of green tea blocks the ability of HIV to enter CD4 cells, according to the results of test tube studies reported by researchers at the University of Sheffield in the United Kingdom and Baylor College of Medicine in Houston. The encouraging research is published in a recent issue of the Journal of Allergy and Clinical Immunology.

Green tea is a nonoxidized, unfermented product of leaves from Camellia sinensis, an evergreen plant. It is made up of catechins, chiefly epigallocatechin gallate (EGCG), and has been credited with possessing health benefits, including cancer and cardiovascular disease prevention properties. Studies have also suggested that EGCG can prevent HIV from binding the CD4 cells, although the reason for this has remained a mystery.

Using the tools of computational and structural biology, the University of Sheffield and Baylor College of Medicine researchers modeled the structure of the EGCG molecule to find the mechanism by which it prevents the HIV gp120 protein from binding to receptors on CD4 cells.

"We found that the EGCG molecule itself binds to the same exact binding pocket on the CD4 molecule at the site of the same amino acids to which gp120 binds," said Baylor's Christina Nance, MD, PhD. "When it binds there, the gp120 envelope protein, and thus HIV, can't."

The Plant

All true teas-as distinct from herbal and flower infusions, which afficiandos call tisanes-are made from the leaves of a magnolia-related evergreen tree with the botanical name of Camellia sinensis. Although reaching a height of 30 feet in the wild, on tea plantations (called gardens or estates), the plant is kept as a shrub, constantly pruned to a height of about 3 feet to encourage new growth and for convenient picking.

Tea plants grow only in warm climates but can flourish at altitudes ranging from sea level to 7,000 feet. The best teas, however, are produced by plants grown at higher altitudes where the leaves mature more slowly and yield a richer flavor. Depending upon the altitude, a new tea plant may take from 2 1⁄2 to 5 years to be ready for commercial picking, but once productive, it can provide tea leaves for close to a century.

Tea plants produce abundant foliage, a camellia-like flower, and a berry, but only the smallest and youngest leaves are picked for tea-the two leaves and bud at the top of each young shoot. The growth of new shoots, called a flush, can occur every week at lower altitudes but takes several weeks at higher ones. The new leaves are picked by hand by "tea pluckers," the best of whom can harvest 40 pounds per day, enough to make 10 pounds of tea.

Green tea is the least processed and thus provides the most antioxidant polyphenols, notably a catechin called epigallocatechin-3-gallate (EGCG), which is believed to be responsible for most of the health benefits linked to green tea. Green tea is made by briefly steaming the just harvested leaves, rendering them soft and pliable and preventing them from fermenting or changing color. After steaming, the leaves are rolled, then spread out and "fired" (dried with hot air or pan-fried in a wok) until they are crisp. The resulting greenish-yellow tea has a green, slightly astringent flavor close to the taste of the fresh leaf.

References used in this website