- Potential effects of tea on health
"This article only deals with the effects of tea which is made from the plant
Camellia sinensis(i.e. black tea, oolong tea, green teaand white tea). This page does not deal with the effects of other teas."
The potential effects of tea on health have been touted for infusions made from the plant "
Camellia sinensis" for more than 4700 years, ever since its discovery was attributed to the legendary emperor, Shennong. The "Shen Nong Ben Cao Jing" claimed its taste and stimulative properties were useful for treating tumors, abscesses, bladder ailments, and lethargy, among other conditions. [N. H. Woodward, "Teas of the World" (1980), as cited in D. A. Balentine, M. E. Harbowy, H. N. Graham, "Tea: The Plant and Its Manufacture; Chemistry and Consumption of the Beverage" in "Caffeine" ed G. Spiller (1998)] The possible beneficial health effects of tea consumption have been suggested and supported by some studies, but others have found no beneficial effects. The studies contrast other claims, including antinutritional effects such as preventing absorptionof ironand protein, usually attributed to tannin. The vast majority of studies have been of green tea; however, some studies have been made of the other types of tea derived from "Camellia sinensis", such as white, oolong, and black tea. Green tea has been claimed [ [http://www.umm.edu/altmed/ConsHerbs/GreenTeach.html Green Tea] : from the University of Maryland Medical Center Alternative/Complementary Medicine library] to be helpful for atherosclerosis, LDL cholesterol, cancer, inflammatory bowel disease, diabetes, liver disease, weight loss, neurodegenerative diseases, and even halitosis.
An article in "
New Scientist" magazine [New Scientist, 20 March 2004] mentions that numerous studies suggest that green teaprotects against a range of cancers, including lung, prostate and breast cancer. The reason cited is the antioxidant epigallocatechin gallate(EGCG), according to Hirofumi Tachibana's team at Kyushu Universityin Japan. Their research showed that growth of human lung cancer cells with a cell receptor called "67 LR" is slowed significantly after drinking just two or three cups of green tea, which contains EGCG. The research also showed that 67 LR is involved in the propagation of priondiseases such as human Creutzfeldt-Jakob(related to mad cow diseasein animals). This is not direct evidence of tea's effect on prion diseases, but a hint that EGCG's effect on 67 LR is an interesting lead in the search for treatments. [Hirofumi Tachibana, Kiyoshi Koga, Yoshinori Fujimura & Koji Yamada; A receptor for green tea polyphenol EGCG, Nature Structural and Molecular Biology", 2004, http://dx.doi.org/doi:10.1038/nsmb743]
According to the U.S. National Cancer Institute, in laboratory studies using animals,
catechinsinactivated oxidants before cell damage occurred, reduced the number and size of tumors, and inhibited the growth of cancer cells.Fact|date=February 2007 White teahas been claimed to be even more effective, based upon preliminary work by Santana-Rios et al. [Santana Rios, G.; Orner, G. A.; Amantana, A.; Provost, C.; Wu, S-Y.; Dashwood, R. H.; "Potent antimutagenic activity of white tea in comparison with green tea in the Salmonella assay" Mutation Research, 495 61-74 (2001)]
Another study from the Life Science journal "Carcinogenesis" demonstrated that green tea, in combination with
tamoxifen, is effective in suppressing breast cancer growth " in vitro" human breast cancer tumors and " in vivo" animal experiments in mice. [ [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16785249 "The combination of green tea and tamoxifen is effective against breast cancer." Sartippour MR, et al. Carcinogenesis. 2006 Dec;27(12):2424-33. Epub 2006 Jun 19.] ]
The anticarcinogenic effect of green tea on gastric cancer was refuted by a large-scale, population-based, prospective cohort study in Japan that involved more than 26,000 residents. [New England Journal of Medicine 2001;344:632, Tsubono F, Nishino Y] Several case control studies suggest an inverse relation between green tea consumption and gastric cancer. Further evaluation is needed to assess the role of green tea and gastric cancer reduction. [Textbook of Gastroenterology, Volume one, 4th edition, 2003 Editor Tadataka Yamada, Lippincott Williams and Wilkins, page 1418]
Topical applications of green tea extracts (EGCG) have protective effects on UVA- and UVB-induced skin damage (
photoagingand carcinogenesis).cite journal |author=Katiyar S, Elmets CA, Katiyar SK |title=Green tea and skin cancer: photoimmunology, angiogenesis and DNA repair |journal=J. Nutr. Biochem. |volume=18 |issue=5 |pages=287–96 |year=2007 |pmid=17049833 |doi=10.1016/j.jnutbio.2006.08.004] cite journal |author=Morley N, Clifford T, Salter L, Campbell S, Gould D, Curnow A |title=The green tea polyphenol (-)-epigallocatechin gallate and green tea can protect human cellular DNA from ultraviolet and visible radiation-induced damage |journal=Photodermatol Photoimmunol Photomed |volume=21 |issue=1 |pages=15–22 |year=2005 |pmid=15634219 |doi=10.1111/j.1600-0781.2005.00119.x] cite journal |author=Luo D, Min W, Lin XF, Wu D, Xu Y, Miao X |title=Effect of epigallocatechingallate on ultraviolet B-induced photo-damage in keratinocyte cell line |journal=Am. J. Chin. Med. |volume=34 |issue=5 |pages=911–22 |year=2006 |pmid=17080554 |doi=] cite journal |author=Wu ZH, Wang MR, Yan QC, Pu W, Zhang JS |title= [UV-induced DNA damage and protective effects of antioxidants on DNA damage in human lens epithelial cells studied with comet assay] |language=Chinese |journal=Zhonghua Yan Ke Za Zhi |volume=42 |issue=11 |pages=1002–7 |year=2006 |pmid=17386139 |doi=] cite journal |author=Sevin A, Oztaş P, Senen D, "et al" |title=Effects of polyphenols on skin damage due to ultraviolet A rays: an experimental study on rats |journal=J Eur Acad Dermatol Venereol |volume=21 |issue=5 |pages=650–6 |year=2007 |pmid=17447979 |doi=10.1111/j.1468-3083.2006.02045.x] cite journal |author=Zhu J, Luo D, Shen CH, Xu J |title= [Photo-protection of epigallocatethi-3-gallate on aging and gene mutation of human skin fibroblasts caused by ultraviolet radiation: an in vitro experiment] |language=Chinese |journal=Zhonghua Yi Xue Za Zhi |volume=87 |issue=20 |pages=1398–401 |year=2007 |pmid=17785060 |doi=] cite journal |author=Yang SW, Lee BR, Koh JW |title=Protective effects of epigallocatechin gallate after UV irradiation in cultured human retinal pigment epithelial cells |journal=Korean J Ophthalmol |volume=21 |issue=4 |pages=232–7 |year=2007 |pmid=18063889 |doi=10.3341/kjo.2007.21.4.232 |doi_brokendate=2008-06-21] cite journal |author=Bae JY, Choi JS, Choi YJ, "et al" |title=(-)Epigallocatechin gallate hampers collagen destruction and collagenase activation in ultraviolet-B-irradiated human dermal fibroblasts: Involvement of mitogen-activated protein kinase |journal=Food Chem. Toxicol. |volume=46 |issue=4 |pages=1298–307 |year=2008 |pmid=18226437 |doi=10.1016/j.fct.2007.09.112]
Increases metabolic rate
Clinical trials conducted by the University of Genevaand the University of Birminghamindicate that green tea raises metabolic rates, speeds up fat oxidation and improves insulin sensitivity and glucose tolerance.cite journal |author=Venables MC, Hulston CJ, Cox HR, Jeukendrup AE |title=Green tea extract ingestion, fat oxidation, and glucose tolerance in healthy humans |journal=Am. J. Clin. Nutr. |volume=87 |issue=3 |pages=778–84 |year=2008 |pmid=18326618 |doi=] In addition to caffeine, green tea contains catechin polyphenols that raise thermogenesis(the rate at which calories are burned), and hence increases energy expenditure.cite journal |author=Dulloo AG, Duret C, Rohrer D, "et al" |title=Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans |journal=Am. J. Clin. Nutr. |volume=70 |issue=6 |pages=1040–5 |year=1999 |pmid=10584049 |doi=]
There is also a suggestion that it can increase endurance in exercise by improving fat metabolism.cite journal |author=Murase T, Haramizu S, Shimotoyodome A, Tokimitsu I, Hase T |title=Green tea extract improves running endurance in mice by stimulating lipid utilization during exercise |journal=Am. J. Physiol. Regul. Integr. Comp. Physiol. |volume=290 |issue=6 |pages=R1550–6 |year=2006 |pmid=16410398 |doi=10.1152/ajpregu.00752.2005]
Possible anti-diabetes effect
There is also epidemiological evidence that drinking green tea (but not
black teaor oolong tea) may help prevent diabetes,cite journal | title=The Relationship between Green Tea and Total Caffeine Intake and Risk for Self-Reported Type 2 Diabetes among Japanese Adults | author=Iso H "et al." | year=2006 | volume=144 | issue=8 | pages=554–62 ] although it is worth noting that this is evidence of an association, and that future studies are needed to confirm the effect.
Boosts mental alertness
amino acid L-theanine, found almost exclusively in the tea plant, actively alters the attention networks of the brain, according to results of human trials announced in September 2007. John Foxe, Ph.D., professor of neuroscience, biology and psychology at City College of the City University of New York, found that theanine is absorbed by the small intestine and crosses the blood-brain barrier, where it affects the brain's neurotransmitters and increases alpha brain-wave activity. The result is a calmer, yet more alert, state of mind. [ [http://sev.prnewswire.com/food-beverages/20070918/NYTU00718092007-1.html Fourth International Scientific Symposium on Tea & Human Health] ] [Juneja, LR, Chu, DC, Okubo, T, Nagato, Y, & Yokogoshi, H. (1999). L-Theanine - a unique amino acid of green tea and its relaxation effect in humans. "Trends in Food Science & Technology", 10(2), 199-204.]
Boosts immune system
21 April 2003the Brigham and Women's Hospitalreleased details of a research project which indicated that theanine may help the body's immune system response when fighting infection, by boosting the disease-fighting capacity of gamma delta T cells. The study included a four-week trial with 11 coffee drinkers and 10 tea drinkers, who consumed 600ml of coffee or black tea daily. Blood sample analysis found that the production of anti-bacterial proteins was up to five times higher in the tea-drinkers, an indicator of a stronger immune response. [ [http://www.brighamandwomens.org/publicaffairs/Newsreleases/tea_immunity_04_21_03.aspx Drinking Tea May Boost Immune System] ]
Lowers chances of cognitive impairment
2006study ["The American Journal of Clinical Nutrition"(Vol. 83,pp.355-361).] [ [http://www.foodnavigator.com/news/ng.asp?id=66142Green tea could protect against Alzheimer’s] ] showed thatelderly Japanese people who consumed more than 2 cups of green tea aday had a 50 percent lower chance of having cognitive impairment, incomparison to those who drank fewer than 2 cups a day, or who consumedother tested beverages. This is probably due to the effect of EGCG,which passes through the blood-brain barrier.
Lowers stress hormone levels
According to a study [ [http://www.ucl.ac.uk/media/library/tea Black tea soothes away stress] ] by UCL researchers, drinking black tea lowers stress hormone levels. Just 50 minutes after a high stress event, tea drinkers, who had been drinking 4 cups of black tea daily for a month, had a 20% greater drop in
cortisolthan the placebo group. Blood platelet activation, which is linked to blood clotting and the risk of heart attacks was also lower for tea drinkers.
Effects on HIV
A recent study appearing in the
Journal of Allergy and Clinical Immunologystated that epigallocatechin gallate (EGCG) found in green tea can lead to the inhibition of HIV virus binding and may be used as a complementary therapy for HIV patients. [cite paper
last = C.L. Nance, M.P. Williamson, T.G. McCormick, S.M. Paulson, W.T. Shearer
title = Epigallocatechin Gallate, Green Tea Catechin, Binds to the T Cell Receptor, CD4
Journal of Allergy and Clinical Immunology
date = 2-1-2006
accessdate = 12-10-2007] [cite news
title = Green tea 'may keep HIV at bay
url = http://news.bbc.co.uk/2/hi/health/6502399.stm
EGCG does this by competing for
gp120binding sites with HIV, and also protects the brain, which modern anti-retroviralsmedicines cannot do, since they can't pass the blood brain barrierdubious. This is one reason why HIV cannot currently be eliminated as modern medicines cannot penetrate the testes, [cite news
title = Men's testicles HIV hiding spot
url = http://news.bbc.co.uk/2/hi/health/6323191.stm
BBC News] brain, and Kupffer cellsof the liver, [ [http://gateway.nlm.nih.gov/MeetingAbstracts/102198232.html Human Kupffer cells are target cells of HIV-1 in vivo] ] where HIV regroups.
Oxalates, including those found in all teas, help with HIV and general infections by mopping up free iron, leaving one less thing for the immune system to do.Fact|date=November 2007 Oxalates chelate zincas well, a crucial nutrient HIVuses to hijack a cell, as it has zinc fingers. However, oxalates are a mixed bag - see the problems below.
Effects on inflammatory bowel disease (IBD)
The polyphenols in green tea have been shown to reduce intestinal inflammation in mouse models of IBD. This effect seems to be related to tea’s ability to interupt the cascade of inflamitory reactions that are the cause of IBD. (Reference: Textbook of Gastroenterology, Volume one, 4th edition, 2003 Editor Tadataka Yamada, Lippincott Williams and Wilkins, pages 1141-1142).
Effects on bad breath
Researchers at the
University of Illinois at Chicagostated that polyphenols help inhibit the growth of bacteria that cause bad breath. [ [http://www.eurekalert.org/pub_releases/2003-05/uoia-tfb051403.php Tea fights bad breath ] ]
Iron overload disorders
Researchers in Germany have found that a daily cup of black tea can help stop excess iron damaging the bodies of people who suffer from
haemochromatosisdue to its high content of tannin, which limits iron absorption. [ [http://members.tripod.com/~hemochromatose/onderwerpen/teabbc BBC News | Health | Cuppa a day is a lifesaver ] ]
Effects associated with caffeine
A cup of green tea contains between 15 and 50 mg of caffeine. Certain cognitive benefits are associated with caffeine consumption, such as a reduction in the likelihood of
Parkinson's diseaseand a temporary increase in short term memory. Further, caffeine consumption has been linked with greater athletic performance, healthy weight loss, reduction in duration and severity of headaches and is effective in treating the symptoms of asthma. [ [http://men.webmd.com/features/coffee-new-health-food Health Benefits of Coffee - WebMD ] ]
Effects on obstructive sleep apnea-related brain deficits
University of Louisville researchers report that green tea polyphenols may stave off the cognitive deficits that occur with obstructive sleep apnea, in the second issue for May, 2008 of the American Thoracic Society’s "American Journal of Respiratory and Critical Care Medicine" [ [http://www.newswise.com/articles/view/540745/ Newswise: Green Tea Compounds Beat OSA-Related Brain Deficits] ] . Researchers examined the effects of green tea polyphenols administered through drinking water, on rats that were intermittently deprived of oxygen during 12-hour “night” cycles, mimicking the intermittent hypoxia that humans with OSA experience.
Effects on bacterial and fungal infections
A study at Pace University reported in
American Society For Microbiology(May 2008) found that white tea extracts effective at treating bacterial infections, such as Staphylococcus, Streptococcus, pneumoniaand dental caries[ [http://www.sciencedaily.com/releases/2004/05/040526070934.htm White Tea Beats Green Tea In Fighting Germs] ] . White tea was also found to be effective in treating fungal infections from Penicillium chrysogenumand Saccharomyces cerevisiae. Researchers also reported that white tea extracts showed a greater effect than green tea extracts.
Antivenin activity of melanin extracted from black tea (MEBT) was reported for the first time in 2004. [ [http://cat.inist.fr/?aModele=afficheN&cpsidt=15489455 Inhibitory effect and Anti-venin effect of MEBT ] ] Low toxicity of MEBT in combination with its antagonistic activity against different venoms may allow effective life-saving treatment against snakebites. Such application of MEBT is important when identification of the snake is impossible or if specific treatment is unavailable.
Effects of fluoride
All tea leaves contain
fluoride; however, mature leaves contain as much as 10 to 20 times the fluoride levels of young leaves from the same plant. [cite journal
title = Aluminium and fluoride contents of tea, with emphasis on brick tea and their health implications
author = M. H. Wong, K. F. Fung and H. P. Carr
journal = Toxicology Letters
volume = 137
issue = 12
pages = 111–120
year = 2003
doi = 10.1016/S0378-4274(02)00385-5 ] [cite journal
title = Fluoride Content in Tea and Its Relationship with Tea Quality
author = Yi Lu, Wen-Fei Guo, and Xian-Qiang Yang
journal = J. Agric. Food Chem.
volume = 52
issue = 14
pages = 4472–4476
year = 2004
doi = 10.1021/jf0308354 S0021-8561(03)00835-5 ] [cite journal
title = Fluoride contents in tea and soil from tea plantations and the release of fluoride into tea liquor during infusion
author = K. F. Fung, Z. Q. Zhang1, J. W. C. Wong and M. H. Wong
journal = Environmental Pollution
volume = 104
issue = 2
pages = 197–205
year = 1999
doi = 10.1016/S0269-7491(98)00187-0 ] cite journal |author=Lung SC, Cheng HW, Fu CB |title=Potential exposure and risk of fluoride intakes from tea drinks produced in Taiwan |journal=J Expo Sci Environ Epidemiol |volume=18 |issue=2 |pages=158–66 |year=2008 |pmid=17410113 |doi=10.1038/sj.jes.7500574] cite journal |author=Malinowska E, Inkielewicz I, Czarnowski W, Szefer P |title=Assessment of fluoride concentration and daily intake by human from tea and herbal infusions |journal=Food Chem. Toxicol. |volume=46 |issue=3 |pages=1055–61 |year=2008 |pmid=18078704 |doi=10.1016/j.fct.2007.10.039] [ [http://www.foodnavigator-usa.com/news/ng.asp?id=58604-calls-for-fda Calls for FDA to introduce tea fluoride safety standard ] ] In general, the level of fluoride in tea is inversely related to the EGCG contents: the more EGCG, the less fluoride.
White teacontains less fluoride than green teaand black tea, because it is made of buds and young leaves only.
The fluoride content of tea depends directly on soil and air pollution; tea plants absorbs this element at a greater rate than other plants. Care in the choice of the location where the plant is grown may reduce the risk. [cite journal
title = Accumulation of Fluoride and Aluminium Related to Different Varieties of Tea Plant
author = Jianyun Ruan and Ming H. Wong
journal = Environmental Geochemistry and Health
volume = 23
issue = 1
pages = 53–63
year = 2001
doi = 10.1023/A:1011082608631 ]
According to Andreas Schuld of the Canadian Parents of Fluoride Poisoned Children, tea is very high in fluoride content, much higher than the
Maximum Contaminant Level(MCL) set for fluoride in drinking water. [http://www.bruha.com/pfpc/html/green_tea___.html Green Tea ] ] Decaffeinated teas have an even higher fluoride content, which is thought to be due to high fluoride levels in the water used in decaffeination. According to Schuld, fluoride could reduce the anti-cancer properties of tea, or even possibly cause cancer at continued toxic levels of the mineral. For instance, Schuld references a 1998 study which found positive correlation between colon cancer and tea intake. The high fluoride content could also cause neurologicaland renaldamage, especially in the presence of aluminum. Additionally, the high fluoride content could cause osteoporosis, arthritis, skeletal fluorosiscite journal |author=Whyte MP, Totty WG, Lim VT, Whitford GM |title=Skeletal Fluorosis From Instant Tea |journal=J Bone Miner Res |volume= 23|issue= |pages=759|year=2008 |pmid=18179362 |doi=10.1359/jbmr.080101] and other bone disorders.
Effects associated with caffeine
Caffeineis an addictive substance and overuse of tea can result in harmful side effects, such as an increased likelihood of certain sleep disorders. Decaffeination reduces total catechins in both black and green dry teas by about 15 times and 3 times respectively. [ Bhagwat, T "et al.", [http://www.nal.usda.gov/fnic/foodcomp/Data/Other/IFT2003_TeaFlav.pdf "Flavonoid composition of tea: Comparison of black and green teas"] , USDA Agricultural Research Service]
oxalate, overconsumption of which can cause kidneydamage, as well as soak up free calciumin the body; other minerals could be soaked up as well. The bioavailability of oxalate from tea is low and because of this a negative effect requires large amounts of tea. [cite journal
title = Low oxalate bioavailability from black tea
author = Michael Liebman and Shawnna Murphy
journal = Nutrition Research
volume = 27
issue = 5
pages = 273–278
year = 2007
doi = 10.1016/j.nutres.2007.04.004 ]
It has been suggested that the chemical known as
tanninmay increase the risk of nasal and esophogeal cancer. [http://findarticles.com/p/articles/mi_m0876/is_n56/ai_9164614] However, some studies have found tea drinking might be negatively associated with risk of esophageal cancer.cite journal |author=Hung HC, Huang MC, Lee JM, Wu DC, Hsu HK, Wu MT |title=Association between diet and esophageal cancer in Taiwan |journal=J. Gastroenterol. Hepatol. |volume=19 |issue=6 |pages=632–7 |year=2004 |pmid=15151616 |doi=10.1111/j.1440-1746.2004.03346.x] cite journal |author=Wang JM, Xu B, Rao JY, Shen HB, Xue HC, Jiang QW |title=Diet habits, alcohol drinking, tobacco smoking, green tea drinking, and the risk of esophageal squamous cell carcinoma in the Chinese population |journal=Eur J Gastroenterol Hepatol |volume=19 |issue=2 |pages=171–6 |year=2007 |pmid=17273005 |doi=10.1097/MEG.0b013e32800ff77a]
United States FDA
In a July 2005 review of claims made about the health benefits of green tea, the U.S.
Food and Drug Administrationconcluded that it was highly unlikely that green tea reduces the risk of breastand prostate cancer. The FDA believes that the evidence does not support qualified health claims for green tea consumption and a reduced risk of cancer. [ [http://www.fda.gov/bbs/topics/NEWS/2005/NEW01197.html FDA Issues Information for Consumers about Claims for Green Tea and Certain Cancers] ]
Effect of milk on tea
A studycite journal
title = Addition of milk prevents vascular protective effects of tea
author = Mario Lorenz, Nicoline Jochmann, Amélie von Krosigk, Peter Martus, Gert Baumann, Karl Stangl and Verena Stangl
journal = European Heart Journal
volume = 28
issue = 2
pages = 219–223
year = 2007
doi = 10.1093/eurheartj/ehl442
pmid = 17213230 ] at the Charité Hospital of the Berlin Universities showed that adding
milkto tea will block the normal, healthful effects that tea has in protecting against cardiovascular disease. This occurs because caseinfrom the milk binds to the molecules in tea that cause the arteries to relax, especially EGCG. Milk may also block tea's effect on other things, such as cancer. [ [http://www.newscientist.com/article/dn10913 Milk wrecks the health benefits of tea, New Scientist, 9 January 2007] ] Other studies have found little to no effect from milk on the observed increase in total plasma antioxidant activity. [Vijayakumar C. Reddy, G.V. Vidya Sagar, D. Sreeramulu, L. Venu, M. Raghunath, "Addition of Milk Does Not Alter the Antioxidant Activity of Black Tea", Annals of Nutrition and Metabolism 2005;49:189-195 PMID 16020939 [http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowPDF&ProduktNr=223977&Ausgabe=231143&ArtikelNr=87071&filename=87071.pdf] ] Teas with high EGCG content, such as green tea, are not typically consumed with milk. Previous studies have observed a beneficial effect from black tea which was not attributable to the catechin content. [Widlansky ME, Duffy SJ, Hamburg NM, Gokce N, Warden BA, Wiseman S, Keaney JF Jr, Frei B, Vita JA. "Effects of black tea consumption on plasma catechins and markers of oxidative stress and inflammation in patients with coronary artery disease." Free Radic Biol Med. 2005 February 15;38(4):499-506. PMID 15649652] Plant-based "milks", such as soy milk, do not contain casein and are not known to have similar effects on tea.
Milk also binds the
tanninin the tea, rendering it harmless. [ [http://findarticles.com/p/articles/mi_m0876/is_n56/ai_9164614 "Some tea and wine may cause cancer - tannin, found in tea and red wine, linked to esophageal cancer"] " Nutrition Health Review", Fall, 1990 ]
* [http://www.eurekalert.org/pub_releases/2005-01/aps-gte012705.php Some evidence for the benefits of green tea for endurance in exercise]
* [http://www.cancer.gov/newscenter/pressreleases/tea Tea and Cancer Prevention] - National Cancer Institute press release
* [http://www.webmd.com/content/article/112/110306.htm Antioxidant in Green Tea May Fight Alzheimer's, (EGCG)]
* [http://news.bbc.co.uk/2/hi/health/5281046.stm "Tea 'healthier' drink than water"] -
BBCarticle, 24 August 2006
* [http://www.cbsnews.com/stories/2006/12/04/earlyshow/contributors/emilysenay/main2224186.shtml Green tea might prolong life and help skin damaged from radiation therapy]
* [http://www.whfoods.com/genpage.php?tname=foodspice&dbid=146 The World's Healthiest Foods - Green tea]
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