Natural support for healthy weight control.[ILLUSTRATION OMITTED] Scientific research on the health benefits of green tea is expanding exponentially, with more than 1,500 articles published in prestigious journals over the last five years alone. [ILLUSTRATION OMITTED] While green tea's medicinal properties have been described for more than 1,000 years, one of its most timely benefits may be supporting weight management by increasing metabolism and promoting fat burning. With nearly two thirds of the American population now overweight or obese--and thus at heightened risk for metabolic syndrome metabolic syndrome n. See syndrome X. Metabolic syndrome A group of risk factors for heart disease, diabetes, and stroke. , heart disease, cancer, and other life-threatening ailments--effective weight-control strategies are fast becoming a matter of life and death
"Matter of Life and Death" was the second episode of the first series of . . In addition to promoting healthy body weight and composition, green tea may help ward off numerous health conditions that afflict aging adults, from cataracts to autoimmune disorders Autoimmune Disorders Definition Autoimmune disorders are conditions in which a person's immune system attacks the body's own cells, causing tissue destruction. . Green tea's health-promoting properties have even been recognized by the FDA FDA abbr. Food and Drug Administration FDA, n.pr See Food and Drug Administration. FDA, n.pr the abbreviation for the Food and Drug Administration. , which recently approved the first prescription drug prescription drug Prescription medication Pharmacology An FDA-approved drug which must, by federal law or regulation, be dispensed only pursuant to a prescription–eg, finished dose form and active ingredients subject to the provisos of the Federal Food, Drug, derived from green tea. In this article, we examine compelling research supporting green tea's role in helping to achieve and maintain a healthy body weight, along with myriad studies testifying to its broad-spectrum effects in promoting optimal health and well-being. GREEN TEA SUPPORTS HEALTHY BODY MASS AND COMPOSITION America's looming obesity epidemic has spurred scientists to seek new agents that promote healthy body weight and composition. Certain spicy foods and herbal drinks have long been used as weight-management tools because of their purported ability to promote thermogenesis thermogenesis /ther·mo·gen·e·sis/ (-jen´e-sis) the production of heat, especially within the animal body.thermogenet´icthermogen´ic ther·mo·gen·e·sis n. or satiety satiety being in a state of satiation; in experimental animals used with reference to eating and drinking. satiety center located in the ventromedial hypothalamic nucleus. . Scientists have proposed that such agents--like ginger and black pepper--may help prevent excessive weight gain and obesity via these mechanisms. (1) During the past decade, green tea has received particular attention for its role in promoting healthy weight management. Its weight-control effects have been studied extensively in cell, animal, and human studies. Laboratory and animal models suggest that green tea, green tea polyphenols known as catechins, and green tea's principal catechin catechin /cat·e·chin/ (kat´e-kin) an astringent principle from the heartwood of Acacia catechu (catechu) and Uncaria gambier (gambir). , EGCG EGCG Epigallocatechin Gallate (antioxidant in green tea) , may work to promote healthy weight management by: * reducing fat cell proliferation * decreasing body and fat mass * inhibiting fat absorption * lowering blood levels of triglycerides Triglycerides Fatty compounds synthesized from carbohydrates during the process of digestion and stored in the body's adipose (fat) tissues. High levels of triglycerides in the blood are associated with insulin resistance. , cholesterol, glucose, and insulin. At the same time, green tea has been found to increase the oxidation (breakdown) of fats. Human studies suggest that green tea consumption is associated with decreased body mass and body fat. (2) GREEN TEA PROMOTES THERMOGENESIS Earlier research suggested that caffeine in green tea might be responsible for its thermogenic ther·mo·gen·e·sis n. Generation or production of heat, especially by physiological processes. ther effect. Later studies, however, reported that green tea's thermogenic effects were too great to be attributed to caffeine alone. Instead, scientists proposed that green tea polyphenols may work in synergy with caffeine to promote thermogenesis. (8) [ILLUSTRATION OMITTED] According to recent findings, EGCG may be an important contributor to green tea's effects in promoting thermogenesis and healthy weight control. Scientists believe EGCG works by inhibiting catechol-O-methyltransferase, an enzyme that degrades norepinephrine norepinephrine (nôr'ĕpīnĕf`rən), a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous system. . Produced by the adrenal glands Adrenal glands The two glands that are located on top of the kidneys. These glands secrete several hormones, including the glucocorticoids which, among other things, influence the way the immune system works, and the mineralocorticoids, which affect retention of in response to stress, the hormone norepinephrine increases metabolic rate, which likely contributes to green tea's effects on thermogenesis. (9) GREEN TEA INHIBITS FAT DIGESTION AND ABSORPTION Several years ago, scientists suggested a possible mechanism by which green tea may guard against excess body weight. In the laboratory, scientists found that a green tea extract inhibited fat-digesting lipase lipase (lī`pās), any enzyme capable of degrading lipid molecules. The bulk of dietary lipids are a class called triacylglycerols and are attacked by lipases to yield simple fatty acids and glycerol, molecules which can permeate the membranes enzymes of the stomach and pancreas. By inhibiting fat-digesting enzymes, green tea likely reduces fat digestion in humans, thus averting some of the dangers of consuming excess fat calories. (10) A recent human study provides support for these earlier findings. In a trial published last year in the European Journal of Clinical Nutrition Clinical nutrition The use of diet and nutritional supplements as a way to enhance health prevent disease. Mentioned in: Naturopathic Medicine , researchers found that polyphenol-enriched oolong oo·long n. A dark Chinese tea that has been partially fermented before drying. [Chinese (Mandarin) w tea (a partially fermented cousin of green tea) helps promote the fecal excretion of lipids following consumption of fatty foods. In a well-designed study, 12 healthy adults consumed a large quantity of fat from potato chips twice daily, along with either a placebo drink or polyphenol-rich tea three times daily. Tea consumption led to an increased fecal excretion of dietary fats, suggesting that tea polyphenols guard against the dangers of excessive dietary fat absorption.11 Based on this study, it might be prudent to take two high-potency green tea capsules, or drink several cups of green tea with fatty meals. GREEN TEA PROMOTES FAT BURNING, SUPPORTS HEALTHY BODY WEIGHT An animal study provides important clues to green tea's effects on body weight. Scientists fed mice a high-fat diet high-fat diet A diet rich in fats, often saturated–animal or tropical oils—fats Adverse effects Arthritis, CA, vascular disease, DM, HTN, obesity, stroke. See Fat, Fatty acids, Saturated fat acis, Cf Low-fat diet. in order to induce obesity, and then supplemented the mice with EGCG and monitored biochemical and metabolic changes in the animals. EGCG helped reduce the accumulation of additional body fat, even though food intake remained unchanged. Furthermore, the EGCG-supplemented mice displayed metabolic changes suggestive of suggestive of Decision making adjective Referring to a pattern by LM or imaging, that the interpreter associates with a particular–usually malignant lesion. See Aunt Millie approach, Defensive medicine. increased fat burning. Dietary EGCG consumption thus reduced the gain of fat mass. This may have resulted from increased fat burning, reduced digestibility digestibility the proportion of a feed or diet which can be digested by the normal animal of the subject species. digestibility coefficient see digestibility coefficient. of dietary fats, or a combination of factors. (12) GREEN TEA BOOSTS EXERCISE CAPACITY Another animal study suggests that green tea may enhance exercise endurance and fat-burning ability. Scientists noted that when mice were supplemented with green tea extract, their exercise capacity increased substantially. In fact, compared to a control group of animals, mice supplemented with green tea ran 30% longer before becoming exhausted. Additionally, the supplemented mice displayed markers of increased fat oxidation. These findings suggest that green tea improved exercise endurance by increasing the utilization of fatty acids as an energy source during exercise. (13) HUMAN STUDIES CONFIRM GREEN TEA'S EFFECTS Additional human studies support green tea's ability to boost metabolism and support healthy weight management. [ILLUSTRATION OMITTED] A study published in the American Journal of Clinical Nutrition found that green tea extract significantly increased energy expenditure (a measure of metabolism) in adults, while also boosting fat burning. When men supplemented with 90 mg of EGCG and 50 mg of caffeine three times daily, their 24-hour energy expenditure increased by 4%. The supplemented men thus burned 79 more calories a day than men who did not supplement. The increase in energy expenditure came from burning fat, as opposed to a breakdown of protein (muscle) mass. These important findings suggest that green tea extract can be an important tool in maintaining healthy body weight and composition. (14) Another study lends support to green tea's role in healthy weight control in humans. In this trial, moderately obese adults supplemented with a green tea extract. After three months, they demonstrated a 4.6% decrease in body weight and a 4.5% decrease in waist circumference. This important study demonstrates that green tea effectively supports healthy body mass and protects against dangerous excess weight around the abdomen, which is a potent risk factor for metabolic syndrome. (15) GREEN TEA'S APPLICATIONS FOR DISEASE PREVENTION Promoting fat burning and healthy body weight is just one of green tea's many health-boosting benefits. Green tea has shown efficacy against several forms of cancer and a variety of other life-threatening health disorders. Cancer Green tea may offer tremendous potential in cancer prevention and treatment, according to epidemiological, laboratory, animal, and clinical studies conducted in the past 10 years.16 In fact, a recent study led by the US Department of Agriculture reports that green and black teas have potent anti-cancer effects against a wide range of human cancer cells. (17) Green tea's polyphenols--most notably EGCG--are thought to be responsible for these effects. (16) EGCG has been shown to block each stage of carcinogenesis car·ci·no·gen·e·sis n. The production of cancer. carcinogenesis production of cancer. biological carcinogenesis viruses and some parasites are capable of initiating neoplasia. by modulating signaling pathways involved in cell proliferation, transformation, inflammation, suicide (apoptosis), metastasis metastasis /me·tas·ta·sis/ (me-tas´tah-sis) pl. metas´tases 1. transfer of disease from one organ or part of the body to another not directly connected with it, due either to transfer of pathogenic microorganisms or to , and invasion. (18) These findings may hold important applications for a wide range of cancers. Breast Cancer Researchers are especially excited about recent population studies investigating a possible link between tea consumption and protection against breast cancer. A study in Los Angeles County examined the effects of tea consumption on breast cancer risk in Asian-American women of Chinese, Japanese, or Filipino descent. Green tea drinkers enjoyed a significantly reduced risk of breast cancer compared to those who did not drink green tea. Green tea's protective effect was dose dependent, with larger quantities conferring greater breast cancer protection. By contrast, consumption of black tea did not protect the women against breast cancer. (19) [ILLUSTRATION OMITTED] A 2006 meta-analysis published in the journal Carcinogenesis looked at 13 separate epidemiological studies examining the effects of green tea and black tea on breast cancer risk. The findings indicated that green tea consumption was associated with a lower risk for breast cancer, while black tea's effect on breast cancer risk was inconclusive. (20) Green tea may also offer support for those already affected by breast cancer. A Canadian research review and meta-analysis suggested that green tea consumption may help protect against the recurrence of early-stage (Stage I and II) breast cancers. (21) Colon Cancer colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. Preliminary findings suggest that green tea helps to avert colon cancer, one of the leading causes of cancer death in men and women. Epidemiological and laboratory studies suggest that EGCG acts as a potent cancer-preventive agent that suppresses the formation of colorectal cancers and fights colon cancer growth. Scientists believe that green tea may counter colorectal cancer by stimulating cancerous cells to undergo apoptosis. (22) Skin Cancer Ultraviolet light Ultraviolet light A portion of the light spectrum not visible to the eye. Two bands of the UV spectrum, UVA and UVB, are used to treat psoriasis and other skin diseases. is a known carcinogen carcinogen: see cancer. carcinogen Agent that can cause cancer. Exposure to one or more carcinogens, including certain chemicals, radiation, and certain viruses, can initiate cancer under conditions not completely understood. , as repeated exposure can lead to skin cancers. Green tea may protect the skin from the effects of ultraviolet (UV) radiation, with potential applications in preventing skin disorders, including melanoma and other skin cancers. Animal studies show that green tea, consumed orally or applied topically, may protect the skin by preventing inflammation and immune suppression induced by UV light. Treating human skin with EGCG has been shown to inhibit UVB-induced erythema erythema (ĕr'əthē`mə), more or less diffuse redness of the skin due to concentration of an abnormally large amount of blood within the small vessels of the skin (hyperemia), as in burns. (redness), oxidative stress oxidative stress, n an imbalance of the prooxidant antioxidant ratio in which too few antioxidants are produced or ingested or too many oxidizing agents are produced. , inflammation, and biochemical reactions associated with skin cancer induction. Green tea polyphenols may thus help to prevent skin disorders associated with exposure to UVB UVB ultraviolet B; see ultraviolet. light, including photoaging pho·to·ag·ing n. 1. The process by which skin is changed or damaged as a result of exposure to ultraviolet radiation in sunlight and other sources. 2. , melanoma, and non-melanoma skin cancers. (23) Leukemia Early research indicates that EGCG may help to fight chronic lymphocytic leukemia chronic lymphocytic leukemia n. Abbr. CLL Lymphocytic leukemia occurring mainly in older adults, characterized by slow onset and gradual progression of symptoms. , a form of leukemia (cancer of the blood) that affects adults. Mayo Clinic investigators discovered that EGCG helps destroy leukemia cells in culture by interrupting communication between cancerous cells. EGCG prompted leukemia cells to die in 8 of 10 leukemia cell samples tested in a laboratory. (24) Heart Disease Previous studies have suggested that high doses of green tea lower blood cholesterol and slow the progression of atherosclerosis in animal models. (25,26) In a study funded by the National Center for Complementary and Alternative Medicine National Center for Complementary and Alternative Medicine, n.pr established in 1998 as a Center of the National Institutes of Health. Supports and conducts research on complementary and alternative med-icine and informs healthcare pro-fessionals about (a division of the National Institutes of Health), scientists are now examining the cholesterol-lowering action of green tea extracts in postmenopausal post·men·o·paus·al adj. Of or occurring in the time following menopause. postmenopausal Change of life Gynecology adjective Referring to the time in ♀ when menstrual periods stop for ≥ 1 yr females. In the years before menopause, women enjoy a lower risk of coronary heart disease coronary heart disease: see coronary artery disease. coronary heart disease or ischemic heart disease Progressive reduction of blood supply to the heart muscle due to narrowing or blocking of a coronary artery (see atherosclerosis). relative to men of the same age. After menopause, however, a woman's risk for heart disease risk rises substantially. Using an animal model, scientists are investigating whether green tea may help prevent postmenopausal increases in blood cholesterol. (27) Their findings may hold tremendous potential for helping women lower their elevated coronary heart disease risk following menopause. Eye Health and Diabetes Diabetes sufferers are at heightened risk for numerous health disorders, including vision-impairing cataracts. Green tea polyphenols may help diminish the elevated risk of cataracts associated with diabetes. In a study published in 2005, researchers administered green and black teas to diabetic rats for three months. Both kinds of tea inhibited diabetes-induced cataracts, perhaps by modulating elevated glucose levels in the eye lenses. The researchers concluded that green and black teas represent potentially inexpensive, non-toxic agents for preventing or slowing the complications of diabetes in humans. (28) Arthritis Rheumatoid arthritis rheumatoid arthritis Chronic, progressive autoimmune disease causing connective-tissue inflammation, mostly in synovial joints. It can occur at any age, is more common in women, and has an unpredictable course. is an autoimmune condition that can cause fever, joint pain, and impaired mobility. Scientists at the University of Maryland University of Maryland can refer to:
In the laboratory, investigators gave water infused with green tea extract to rats for two weeks, and then induced an experimental form of rheumatoid arthritis. Compared to control rats given regular water, rats fed green tea extract were substantially protected from rheumatoid arthritis symptoms. [ILLUSTRATION OMITTED] Based on these initial findings, the researchers believe that green tea may be a useful addition to conventional anti-arthritis treatments. The National Institutes of Health is funding a larger trial to further explore this possibility. (29) Autoimmune Diseases Autoimmune diseases A group of diseases, like rheumatoid arthritis and systemic lupus erythematosus, in which immune cells turn on the body, attacking various tissues and organs. Mentioned in: Complement Deficiencies, Premature Menopause Green tea's antioxidant antioxidant, substance that prevents or slows the breakdown of another substance by oxygen. Synthetic and natural antioxidants are used to slow the deterioration of gasoline and rubber, and such antioxidants as vitamin C (ascorbic acid), butylated hydroxytoluene and anti-inflammatory effects have led scientists to propose that it may have a role in fighting autoimmune diseases--such as type I diabetes Type I diabetes Also called juvenile diabetes. Type I diabetes typically begins early in life. Affected individuals have a primary insulin deficiency and must take insulin injections. Mentioned in: Diabetic Ketoacidosis , rheumatoid arthritis, lupus, and Sjogren's syndrome--in which the body's immune system immune system Cells, cell products, organs, and structures of the body involved in the detection and destruction of foreign invaders, such as bacteria, viruses, and cancer cells. Immunity is based on the system's ability to launch a defense against such invaders. attacks its own cells and tissues. In Sjogren's syndrome, the immune system attacks the moisture-secreting glands of the mouth and eyes, leading to the disease's most prevalent symptoms of dry mouth (xerostomia xerostomia /xe·ro·sto·mia/ (zer?o-sto´me-ah) dryness of the mouth due to salivary gland dysfunction. xe·ro·sto·mi·a n. ) and dry eyes (xeropthalmia). Sjogren's can occur in isolation or accompany other autoimmune diseases, in which case it is known as secondary Sjogren's. Elderly Americans are more susceptible to secondary Sjogren's than are elderly adults in China and Japan, the top two tea-consuming nations. This has led researchers to postulate that green tea may help protect Asian populations against secondary Sjogren's syndrome. (30) In the laboratory, green tea catechins stimulated changes in human cells that make them less susceptible to autoimmune attack by the immune system. Additionally, green tea dramatically decreased inflammation in healthy tissues, another change indicative of decreased autoimmune activity. (31) These exciting findings suggest that green tea polyphenols may help reduce the incidence and severity of autoimmune diseases. DOSAGE Green tea has demonstrated health-promoting benefits in dosages ranging from 2 to 10 cups of tea daily. (32) Green tea supplements are typically standardized for their content of polyphenols, primarily EGCG. Optimal doses are approximately 1400-2800 mg a day of a green tea extract with a minimum 95% polyphenol polyphenol Any of various alcohols containing two or more benzene rings that each have at least one hydroxyl group (OH) attached. Many polyphenols occur naturally in plants and some kinds, such as the flavonoids and tannins, are believed to be beneficial content, taken with meals. CONCLUSION The health-promoting properties of green tea have been revered for centuries throughout Asia. In the West, a flood of recent research continues to elucidate the remarkable biochemical properties of green tea. Strong scientific evidence suggests that green tea confers critical cardiovascular benefits, may protect against a variety of deadly cancers, reduces the risk of diabetic complications, and may mitigate the effects of various autoimmune disorders. If these broad-spectrum benefits were not reason enough for health-conscious adults to consider adding green tea to their daily supplement regimen, emerging research that confirms green tea's effects in facilitating fat burning, weight management, and optimal body composition surely is. With a majority of Americans now struggling to maintain a healthy body weight, low-cost nutrients like green tea could play an important role in helping to avert an epidemic of obesity and its related health problems. References (1.) Westerterp-Plantenga M, Diepvens K, Joosen AM, Berube-Parent S, Tremblay A. Metabolic effects of spices, teas, and caffeine. Physiol Behav. 2006 Aug 30;89(1):85-91. (2.) Wolfram S, Wang Y, Thielecke F. Anti-obesity effects of green tea: from bedside to bench. Mol Nutr Food Res. 2006 Feb;50 (2):176-87. (3.) Hodgson JM, Puddey IB, Burke V, Beilin LJ, Jordan N. Effects on blood pressure of drinking green and black tea. J Hypertens. 1999 Apr;17(4):457-63. (4.) Available at: http://www.cancer.gov/prevention/agents/Tea_Polyphenols.html. Accessed January 2, 2007. (5.) Rahman I, Biswas SK, Kirkham PA. Regulation of inflammation and redox signaling by dietary polyphenols. Biochem Pharmacol. 2006 Nov 30;72(11):1439-52. (6.) Curin Y, Andriantsitohaina R. Polyphenols as potential therapeutical agents against cardiovascular diseases. Pharmacol Rep. 2005;57 Suppl:97-107. (7.) Meeran SM, Mantena SK, Elmets CA, Katiyar SK. (-)-Epigallocatechin-3-gallate prevents photocarcinogenesis in mice through interleukin-12-dependent DNA repair. Cancer Res. 2006 May 15;66(10):5512-20. (8.) Dulloo AG, Seydoux J, Girardier L, Chantre P, Vandermander J. Green tea and thermogenesis: interactions between catechin-polyphenols, caffeine and sympathetic activity. Int J Obes Relat Metab Disord. 2000 Feb;24(2):252-8. (9.) Shixian Q, Vancrey B, Shi J, Kakuda Y, Jiang Y. Green tea extract thermogenesis-induced weight loss by epigallocatechin gallate inhibition of catechol-o-methyltransferase. J Med Food. 2006;9(4):451-8. (10.) Juhel C, Armand M, Pafumi Y, et al. Green tea extract (AR25) inhibits lipolysis lipolysis /li·pol·y·sis/ (li-pol´i-sis) the splitting up or decomposition of fat.lipolyt´ic li·pol·y·sis n. pl. li·pol·y·ses The hydrolysis of lipids. of triglycerides in gastric and duodenal duodenal /du·o·de·nal/ (doo?o-de´n'l) (doo-od´ah-n'l) of or pertaining to the duodenum. Duodenal Refers to the duodenum, or the first part of the small intestine. medium in vitro. J Nutr Biochem. 2000 Jan;11(1):45-51. (11.) Hsu TF, Kusumoto A, Abe K, et al. Polyphenol-enriched oolong tea increases fecal lipid excretion. Eur J Clin Nutr. 2006 Nov;60(11):1330-6. (12.) Klaus S, Pultz S, Thone-Reineke C, Wolfram S. Epigallocatechin gallate attenuates diet-induced obesity in mice by decreasing energy absorption and increasing fat oxidation. Int J Obes (Lond). 2005 Jun;29(6):615-23. (13.) Murase T, Haramizu S, Shimotoyodome A, Tokimitsu I, Hase T. Green tea extract improves running endurance in mice by stimulating lipid utilization during exercise. Am J Physiol Regul Integr Comp Physiol. 2006 Jun;290(6):R1550-6. (14.) Dulloo AG, Duret C, Rohrer D, et al. Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans. Am J Clin Nutr. 1999 Dec;70(6):1040-5. (15.) Chantre P, Lairon D. Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity. Phytomedicine. 2002 Jan;9(1):3-8. (16.) Chen D, Daniel KG, Kuhn DJ, et al. Green tea and tea polyphenols in cancer prevention. Front Biosci. 2004 Sep 1;9:2618-31. (17.) Friedman M, Mackey BE, Kim HJ, et al. Structure-activity relationships of tea compounds against human cancer cells. J Agric Food Chem. 2007 Jan 24;55(2):243-53. (18.) Na HK, Surh YJ. Intracellular signaling network as a prime chemopreventive target of (-)-epigallocatechin gallate gallate antioxidant used in food preservation, especially in foods containing oils and fats. Includes propyl, octyl and dodecylgallate. . Mol Nutr Food Res. 2006 Feb;50(2):152-9. (19.) Wu AH, Yu MC, Tseng CC, Hankin J, Pike MC. Green tea and risk of breast cancer in Asian Americans. Int J Cancer. 2003 Sep 10;106(4):574-9. (20.) Sun CL, Yuan JM, Koh WP, Yu MC. Green tea, black tea and breast cancer risk: a meta-analysis of epidemiological studies. Carcinogenesis. 2006 Jul;27(7):1310-5. (21.) Seely D, Mills EJ, Wu P, Verma S, Guyatt GH. The effects of green tea consumption on incidence of breast cancer and recurrence of breast cancer: a systematic review and meta-analysis. Integr Cancer Ther. 2005 Jun;4(2):144-55. (22.) Kumar N, Shibata D, Helm J, Coppola D, Malafa M. Green tea polyphenols in the prevention of colon cancer. Front Biosci. 2007;12:2309-15. (23.) Katiyar SK. Skin photoprotection by green tea: antioxidant and immunomodulatory effects. Curr Drug Targets Immune Endocr Metabol Disord. 2003 Sep;3(3):234-42. (24.) Lee YK, Bone ND, Strege AK, et al. VEGF VEGF vascular endothelial growth factor. receptor phosphorylation phosphorylation, chemical process in which a phosphate group is added to an organic molecule. In living cells phosphorylation is associated with respiration, which takes place in the cell's mitochondria, and photosynthesis, which takes place in the chloroplasts. status and apoptosis is modulated by a green tea component, epigallocatechin-3-gallate (EGCG), in B-cell chronic lymphocytic leukemia. Blood. 2004 Aug 1;104(3):788-94. (25.) Lin JK, Lin-Shiau SY. Mechanisms of hypolipidemic and anti-obesity effects of tea and tea polyphenols. Mol Nutr Food Res. 2006 Feb;50(2):211-7. (26.) Riemersma RA, Rice-Evans CA, Tyrrell RM, Clifford MN, Lean ME. Tea flavonoids flavonoids, n.pl common plant pigment compounds that act as antioxidants, enhance the effects of vitamin C, and strengthen connective tissue around capillaries. and cardiovascular health. QJM QJM Quarterly Journal of Medicine (Association of Physicians) QJM Quantified Judgement Model QJM Quantified/Quantitative Judgment Method . 2001 May;94(5):277-82. (27.) Available at: http://nccam.nih.gov/research/extramural/awards/2005/. Accessed January 16, 2007. (28.) Vinson JA, Zhang J. Black and green teas equally inhibit diabetic cataracts in a streptozotocin-induced rat model of diabetes. J Agric Food Chem. 2005 May 4;53(9):3710-3. (29.) Available at: www.centerwatch.com/patient/drugs/dru938.html. Accessed January 16, 2007. (30.) Hsu S, Dickinson D. A new approach to managing oral manifestations of Sjogren's syndrome and skin manifestations of lupus. J Biochem Mol Biol. 2006 May 31;39(3):229-39. (31.) Hsu S, Dickinson DP, Qin H, et al. Inhibition of autoantigen autoantigen /au·to·an·ti·gen/ (-an´ti-jen) an antigen that despite being a normal tissue constituent is the target of a humoral or cell-mediated immune response, as in autoimmune disease. expression by (-)-epigallocatechin-3-gallate (the major constituent of green tea) in normal human cells. J Pharmacol Exp Ther. 2005 Nov;315(2):805-11. (32.) Available at: http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/gre_0319.shtml. Accessed January 24, 2007. (33.) Available at: http://www.fda.gov/cder/foi/label/2006/021902lbl.pdf. Accessed January 4, 2007. GREEN TEA: A POTENT SOURCE OF HEALTH-PROMOTUNG POLYPHENOLS For thousands of years, green tea has been used in traditional Chinese and Indian medicine as a stimulant, a diuretic diuretic (dī'yərĕt`ĭk), drug used to increase urine formation and output. Diuretics are prescribed for the treatment of edema (the accumulation of excess fluids in the tissues of the body), which is often the result of underlying (to promote urine excretion), and an astringent astringent (əstrĭn`jənt), substance that shrinks body tissues. Astringent medicines cause shrinkage of mucous membranes or exposed tissues and are often used internally to check discharge of serum or mucous secretions in sore throat, (to control bleeding and help heal wounds), as well as to improve heart health. Other less widely reported traditional uses of green tea include regulating blood pressure, aiding digestion, and improving mental acuity. (3) Today, hundreds of millions of people around the world drink tea. Of the many varieties to choose from--including black, green, red, and white teas--a preponderance of evidence A standard of proof that must be met by a plaintiff if he or she is to win a civil action. In a civil case, the plaintiff has the burden of proving the facts and claims asserted in the complaint. suggests that the healthiest choice may be green tea, due to its high concentration of powerful antioxidants Antioxidants Substances that reduce the damage of the highly reactive free radicals that are the byproducts of the cells. Mentioned in: Aging, Nutritional Supplements antioxidants, n. . Beneficial polyphenols make up roughly 30-40% of green tea, as opposed to only 3-10% of black tea. Polyphenols in tea are classified as catechins. Of the six catechins in green tea, the most active is epigallocatechin-3-gallate, or EGCG. (4) Green tea catechins scavenge scav·enge v. scav·enged, scav·eng·ing, scav·eng·es v.tr. 1. To search through for salvageable material: scavenged the garbage cans for food scraps. 2. oxygen free radicals, restoring cells to health and reducing inflammation. Because inflammation underlies so many age-related afflictions, green tea may have myriad applications in preventing disease. (5,6) Findings from animal studies suggest that green tea polyphenols promote the repair of damaged DNA DNA: see nucleic acid. DNA or deoxyribonucleic acid One of two types of nucleic acid (the other is RNA); a complex organic compound found in all living cells and many viruses. It is the chemical substance of genes. . Since such damage can lead to cancer, protective agents like green tea may play an important role in preventing cancer. (7) GREEN TEA: WHAT YOU NEED TO KNOW * Throughout history, green tea has been valued as a therapeutic beverage. Modern research confirms green tea's powerful antioxidant, anti-inflammatory, and DNA-protective effects. * One of green tea's most promising applications is supporting weight control and promoting healthy body mass and composition. Green tea works via several mechanisms that include boosting thermogenesis (heat production), inhibiting fat digestion and absorption, promoting fat burning, and boosting exercise capacity. * Human studies confirm that green tea extracts boost metabolic rate and promote optimal weight management. * Green tea may help to prevent and treat numerous types of cancer in adults, including cancers of the breast, colon, skin, and blood. Green tea may also help diminish cardiovascular disease risk, protect against complications of diabetes, and help avert autoimmune diseases. * The FDA has approved a green tea derivative as a topical prescription drug to treat genital warts. FDA APPROVES FIRST DRUG DERIVED FROM GREEN TEA The Food and Drug Administration recently approved a special extract of green tea as a prescription drug for the topical treatment of genital and perianal perianal around the anus. perianal abscess under the skin outside the anal canal. Causes sufficient pain to inhibit defecation. warts caused by the human papilloma virus human papilloma virus n. Abbr. HPV A DNA virus of the genus Papillomavirus, certain types of which cause cutaneous and genital warts in humans, including condyloma acuminatum. (HPV HPV human papillomavirus. HPV abbr. human papilloma virus Human papilloma virus (HPV) ). The drug, Veregen[TM] (kunecatechins) Ointment 15%, a water -based extract of green tea, is the first prescription botanical drug approved under the FDA's 1962 amendments that require all drugs be proven safe and effective prior to marketing in the United States. The drug's active ingredient, kunecatechins, is a proprietary mixture of phytochemicals--including catechins and other constituents--produced from a partially purified water extract of green tea leaves. Catechins constitute 85-95% (by weight) of the total drug substance, with EGCG accounting for 55% of the drug's catechin content. (29,33) The safety and efficacy of Veregen[TM] were analyzed in two prospective, randomized ran·dom·ize tr.v. ran·dom·ized, ran·dom·iz·ing, ran·dom·iz·es To make random in arrangement, especially in order to control the variables in an experiment. , double-blind clinical studies. Nearly 400 adults with external genital or anal warts applied the ointment three times daily for 16 weeks, while a group of control subjects applied an inactive placebo. During the four-month study, 54% of those using Veregen[TM] experienced complete clearance of their condition, compared to only 35% of those using placebo. (29,33) While the drug's mechanism of action has not yet been fully elucidated, scientists believe its potent antioxidant properties may be responsible for some of its effects. |
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