Studies have found that tea helps with the prevention cancer, heart disease, and diabetes; encourages weight loss; lower cholesterol; and bring about mental alertness. Tea also appears to have antimicrobial and immune system boosting qualities, hence maintaining overall wellbeing. We’ve tried to research all the numerous ways that tea does you good and enumerated the major points and studies, so please read up while you enjoy another cup of Rakura.
ANTIOXIDANTS IN TEA
Antioxidants are substances that scavenge free radicals — damaging compounds in the body that alter cells, tamper with DNA (genetic material), and even cause cell death. Antioxidants in tea help to reduce free radicals, which are known to damage cells and possibly lead to heart disease and cancer. Antioxidants have been proven to improve effects of aging as well as repair skin cells. This function can result in overall healthier skin. White, green and black teas have high concentration of antioxidants.
TEA BOOSTS MENTAL ALERTNESS
The amino acid L-theanine, found almost exclusively in the tea plant, affects the brain’s neurotransmitters and increases alpha brain-wave activity. The result is a calmer, yet more alert, state of mind.
TEA & IMMUNITY
The Polyphenols in tea have been shown to help increase the white blood cell count, which is responsible for fighting infection. The high vitamin C content found primarily in Green Tea also helps to strengthen the immune system.
TEA’S ROLE IN CARDIOVASCULAR HEALTH
According to Human population studies, people who regularly consume three or more cups of black Tea per day have a reduced risk of heart disease and stroke. Clinical studies suggest that the risk reduction associated with Tea consumption may be due to improvement in some risk factors for cardiovascular disease, including blood vessel function, platelet function and a reduction in oxidative damage.
While researchers are still examining the various mechanisms by which tea flavonoids function, some studies found multifunctional mechanisms, meaning that several mechanisms work in tandem to collectively improve signs for cardiovascular health. Important areas of tea and cardiovascular health research include blood vessel and endothelial function, or the ability of the blood vessels to dilate to allow for proper blood flow, serum cholesterol levels and Low Density Lipoprotein (LDL) cholesterol oxidation. Each of these factors impact the risk of myocardial infarctions (heart attacks), stroke and cardiovascular disease. Study findings in the area of tea and the reduction in cardiovascular disease risk include the following:
- A total of 3,430 men and women aged 30-70 years from the Saudi Coronary Artery Disease Study were examined and 6.3 per cent were found to have indications of coronary heart disease (CHD). The researchers found that those who drank more than six cups of tea per day (>480 mL) had significantly lower prevalence of CHD than non-tea drinkers, even after adjustment for risk factors like age and smoking. The researchers also found that drinking six or more cups of Black Tea per day was associated with decreased serum cholesterol and triglyceride concentrations.
- The Zutphen study, which assessed 805 male subjects over a period of five years, found that the incidence of fatal and nonfatal first myocardial infarction and mortality from stroke decreased significantly as intake of flavonoids, derived mainly from tea, increased in a dose-dependent manner. A follow-up to this study found that high intake of flavonoids significantly lowered the risk of stroke in study participants.
- A Harvard study examined 340 men and women who had suffered heart attacks and compared them to matched control subjects. They found that those who drank a cup or more of Black Tea daily had a 44 per cent reduction in the risk of heart attack compared to non-tea drinkers.
- Another recent Harvard study of 1,900 people found that those who consumed tea during the year prior to a heart attack were up to 44 per cent more likely to survive over the three to four years following the event. Those who consumed fewer than 14 cups of tea per week experienced a 28 per cent reduced death rate, and those who consumed more than 14 cups of tea per week were found to have a 44 per cent reduced death rate, as compared to non-tea drinkers.
TEA’S ROLE IN CHOLESTEROL REDUCTION
Tea can lower your LDL, or “bad,” cholesterol and increase your HDL, or “good,” cholesterol. Keeping your arteries smooth and Clog free, the same way a drain keeps your Bathroom pipes clear. Researchers believe that the polyphenols in green tea can block or slow the intestinal absorption of blood cholesterol, and even encourage your body to excrete excess cholesterol that can otherwise form clots in your arteries. The mechanism behind the blood cholesterol lowering effects of tea may be rooted in the effect of theaflavins, through interfering with the formation of dietary mixed micelles, which could result in Tea reduced intestinal cholesterol absorption.
- Studies at Vanderbilt University confirm this finding that green tea lowered LDL cholesterol by as much as 16 percent in 12 weeks. High cholesterol is one of the primary risk factors for heart disease.
TEA’S ROLE IN CANCER RISK REDUCTION
Preliminary research suggests that the flavonoids in tea play a role in human cancer risk reduction possibly by combating free radical damage, inhibiting uncontrolled cell growth (cell proliferation), by promoting programmed cell death (apoptosis) and boosting the immune system to help fend off the development and promotion of cancer cells.
- An epidemiological study conducted by the University of North Carolina found consumption of the equivalent of 2.5 cups of tea per day or more was associated with a 60 per cent drop in rectal cancer risk among Russian women from Moscow, as compared to women who drank relatively less than 1.2 cups of tea per day. Those women who drank approximately 1.2 to 2.5 cups of tea per day had a 52 per cent reduction in the risk of rectal cancer.
- Based on data from the NHANES I Follow-Up study (NHEFS), researchers found that tea drinkers had about a 42 per cent reduced risk of colon cancer as compared to non-tea drinkers. Men who drank more than 1.5 cups of tea per day were found to have a 70 per cent lower colon cancer risk.
- Researchers who followed a group of over 34,000 postmenopausal healthy women between 55 – 69 years of age for 12 years found that those consuming high levels of catechins experienced up to a 45 percent decrease in the instances of rectal cancer. Catechins are a class of flavonoids found in tea, fruits and vegetables. Catechins derived from tea were most strongly linked to a decrease in rectal cancer.
- The Iowa Women’s Study, which followed post-menopausal women between the ages of 55 and 69 for eight years, found that participants who drank two or more cups of tea per day had a 32 and 60 percent reduced risk of developing digestive and urinary tract cancers, respectively.
- A study conducted with members of the Shanghai Cohort (18,244 men aged 45-64 years at recruitment with up to 12 years of follow-up) discovered a statistically significant inverse relationship between positive tea polyphenol levels (as measured in urine) and gastric cancer.
- A large population-based case-control study found an inverse relationship between Green Tea consumption and the risk of colon, rectal and pancreatic cancer. Male participants, who drank the equivalent of 4.5 servings of tea per day, had an 18 percent decrease in colon cancer risk and 28 percent decreased risk of rectal cancer. Female participants, who drank 3 servings of tea per day, were observed to have a decreased risk of colon and rectal cancer by 33 percent and 43 percent, respectively. Risk of pancreatic cancer was also reduced in both men and women by 37 percent and 47 percent, respectively.
- Researchers in Taiwan discovered a link between EGCG and cancer risk reduction. The researchers found that the Green Tea polyphenol inhibited proliferation of the cancer cells by inducing cell death and blocking cell cycle progression.
- Researchers at the University of Wisconsin, Madison reviewed the existing literature about tea as a preventative measure for prostate cancer among men. Based on epidemiological, in vitro and in vivo studies, the researchers suggest that tea—especially Green Tea—may be a good public health recommendation that may help prevent prostate cancer.
- According to a study conducted by the University of Arizona, participants who drank iced Black Tea and citrus peel had a 42 percent reduced risk of skin cancer.
- Hot Black Tea consumption is associated with a significantly lower risk of squamous cell carcinoma (SCC), a form of skin cancer; tea concentration (strength), brewing time and temperature all influence the potential protective effects of hot Black Tea on SCC.
- Green Tea polyphenols have cancer prevention potential, especially in the case of solar UV-induced cancer.
- Research suggests that compounds in Green Tea may protect skin from ultraviolet (UV) radiation-induced damage when applied topically.
- Researchers examined the effects of tea and curcumin, a spice and food-coloring agent, on oral cancer in hamsters. Hamsters were treated with a topical cancer-causing solution inside the cheek three times a week for six weeks. Two days after the last treatment of the solution, the hamsters were given Green Tea as drinking fluid or curcumin applied topically three times per week, the combination of Green Tea and curcumin treatment, or no treatment for 18 weeks. At the end of this period, the scientists observed that the combination of tea and curcumin significantly decreased the number of visible tumors and tumor volume. Furthermore, tea alone and in combination with curcumin increased cancer cell death (apoptosis)
- In a recent review of observational studies on tea consumption, flavonoid intake, and lung cancer risk, evidence suggests beneficial associations for green and black tea, especially among never-smokers. The review notes that studies reporting increased risk with high tea intake are older and later published data have not confirmed these concerns. Tea catechins were evaluated for their effects on cell proliferation, apoptosis and associated gene expression in highly metastatic human lung cancer cells. A significant reduction in cell proliferation after exposure to tea catechins was noted. It is suggested that tea compounds can influence genetic alteration to reduce the grown and survival of human lung cancer cells.
- A case-control study conducted in China, which employed 254 patients with histologically confirmed epithelial ovarian cancer and 652 control subjects, determined tea consumption based on a validated questionnaire and found that, after accounting for demographic, lifestyle and familial factors, ovarian cancer risk declined with increasing frequency and duration of overall tea consumption
- A population-based study involving over 61,000 Swedish women aged 40-76 found that drinking Black Tea was associated with a reduced risk of ovarian cancer. The study found that women who drank the most tea—green or black—were least likely to develop ovarian cancer over the 15-year study follow-up. Women who drank two or more cups of tea daily experienced a 46 percent reduction in risk compared to women who reported not drinking tea. Even small amounts of tea (less than one cup per day) reduced risk by 18 percent, while one cup per day reduced risk by 24 percent. Although previous studies evaluating the effects of tea consumption and ovarian cancer found inconsistent results, the researchers noted that the large size of this study and long-term follow-up provides compelling evidence that tea drinking may indeed offer protection against this type of cancer.
- Japanese researchers at Saitoma Cancer Centre Research Institute have found that in heavy consumers of green tea, cancer spread to lymph nodes was less frequent. Women with less aggressive breast cancer who drank more than 5 cups of green tea a day were 50% less likely to have a recurrence than women drinking less than 4 cups daily. Green tea appears to improve prognosis and survival by suppressing spread and growth of breast cancer.
TEA AND NEUROLOGICAL DECLINE
- Newly published research reports that tea polyphenols, particularly (–)-epigallocatechin-3-gallate, are bioavailable to the brain and can act via antioxidant, iron-chelation, signal transduction modulation, and other mechanisms to effect neuroprotective and/or neurorescue action, with potential implications for age-related dementia, Alzheimer’s and Parkinson’s diseases.
- A prospective cohort study of nearly 30,000 Finnish adults aged 25 to 74 years old, who were followed for 13 years, found that tea drinking was associated with a reduced risk of Parkinson’s disease. Among tea drinkers, those who reported drinking three or more cups of tea per day were 69% less likely to develop Parkinson’s disease compared to those who reported not drinking tea.
TEA AND METABOLISM, OBESITY AND BODY COMPOSITION
- Clinical trials conducted by the University of Geneva and the University of Birmingham indicate that green tea raises metabolic rates, speeds up fat oxidation and improves insulin sensitivity and glucose tolerance. In addition to caffeine, green tea contains catechin polyphenols that facilitate the burning of calories. Green Tea extract was found to significantly increase 24-hour energy expenditure and fat oxidation in healthy men. After three months of consumption of Green Tea extract by moderately obese patients, body weight decreased by 4.6 percent and waist circumference decreased by 4.48 percent.
- Japanese researchers found that in a 12-week, double-blind and placebo-controlled study, greet tea catechins led to a reduction in body fat, blood pressure and LDL cholesterol compared to the control group. The authors suggest that Green Tea catechins may help prevent obesity and reduce risk for cardiovascular disease.
TEA’S ROLE IN IMMUNE FUNCTION
The Polyphenols in tea have been shown to help increase the white blood cell count, which is responsible for fighting infection. The high vitamin C content found primarily in Green Tea also helps to strengthen the immune system.
- According to the researcher’s a substance in tea, L-theanine, which primes the immune system in fighting infection, bacteria, viruses and fungi. A subsequent human clinical trial showed that certain immune cells of participants who drank five cups of Black Tea a day for two to four weeks secreted up to four times more interferon, an important part of the body’s immune defense, than at baseline. Consumption of the same amount of coffee for the same duration had no effect on interferon levels. According to the authors, this study suggests that drinking Black Tea provides the body’s immune system with natural resistance to microbial infection.
TEA’S ROLE IN ORAL HEALTH
Tea also contributes to oral health. The flavonoids in tea may inhibit the plaque-forming ability of oral bacteria and the fluoride in tea may support healthy tooth enamel.
- A recent study conducted at the New York University Dental Centre examined the effects of Black Tea extract on dental caries formation in hamsters. Compared to those who were fed water with their food, hamsters, which were fed water with Black Tea, extract developed up to 63.7 percent fewer dental caries
TEA’S NUTRITIONAL VALUES
In addition to valuable antioxidant properties and contributing to our daily fluid intake target of 2.5 liters, tea contains many vitamins, minerals and amino acids that includes
- Vitamins: C, K, B12, B6 and E
- Minerals: Trace amounts of potassium, manganese, magnesium, calcium
- Amino Acids: Tea is a strong source of amino acids including L-theanine.
Although the benefits of tea are numerous, it is important to note that tea does contain minimal doses of caffeine (almost the same as a bar of plain chocolate) that can be beneficial to a regular tea drinker’s health, it is best to use caution and limit intake to less than 200mg (about 4 cups) a day for caffeine sensitive individuals and pregnant women. During pregnancy, caffeine may inhibit iron absorption and increase the load on the liver that is already busy processing various pregnancy hormones.
For Pregnant and caffeine sensitive individual, we recommend the Do-it-yourself Decaf
- Caffeine is the first substance released into the water during steeping (this occurs within the first 25 seconds). To decaffeinate your tea, steep the leaves or bag for 30 seconds, dump the water, then refill your cup with hot water and steep again. Most of the caffeine will be removed.
1) Song WO, Chun OK. Tea is the major source of flavan-3-ol and flavonol in the U.S. diet. J Nutr. 2008; 138:1543S–7S.
2) Henning SM, Choo JJ, Heber D. Nongallated compared with gallated flavan-3-ols in green and black tea are more bioavailable. J Nutr. 2008; 138:1529S–34S.
3) Auger C, Mullen W, Hara Y, Crozier A. Bioavailability of polyphenon E flavan-3-ols in humans with an ileostomy. J Nutr. 2008; 138:1535S–42S.
4) Bolling BW, Chen CY, Blumberg JB. Tea and health: Preventive and therapeutic usefulness in the elderly? Curr Opin Clin Nutr Metab Care. 2009 Jan; 12(1): 42-8.
5) Weisburger JH. Tea and health: the underlying mechanisms. Proc Soc Exp Biol Med 1999; 220:271-5.
6) Hertog MGL, Feskens EJM, Hollman PCH, et al. Dietary antioxidant flavonoids and risk of coronary disease: the Zutphen Elderly Study. Lancet 1993; 342:1007-11.
7) Keli SO, Hertog MGL, Feskens EJM, Kromhout D. Dietary flavonoids, antioxidant vitamins, and incidence of stroke. Arch Intern Med 1996; 156:637-42.
8) Duffy SJ, Keaney JF Jr, Holbrook M, Gokce N, Swerdloff PL, Frei B, Vita JA. Short- and long-term black tea consumption reverses endothelial dysfunction in patients with coronary artery disease. Circulation 2001; 104:151-6.
9) Isemura M, Saeki K, Kimura T, Hayakawa S, Minami T, Sazuka M. Tea catechins and related polyphenols as anti-cancer agents. Biofactors. 2000;13(1-4):81-5.
10) Mandel SA, Amit T, Kalfon L, Reznichenko L, Youdim MBH. Targeting multiple neurodegenerative diseases etiologies with multimodal-acting green tea catechins. J Nutr. 2008;138:1578S–83S.
11) Kelly SP, Gomez-Ramirez M, Montesi JL, Foxe JJ. L-Theanine and caffeine in combination affect human cognition as evidenced by oscillatory alpha-band activity and attention task performance. J Nutr. 2008; 138:1572S–7S.
12) Sarkar, S., Sett, P., Chowdhury, T., and Ganguly, D.K. Effect of black tea on teeth. J Indian Soc Pedod Prev Dent 2000; 18:139-140.
13) Hegarty VM, May HM, Khaw K-T. Tea drinking and bone mineral density in older women. Am J Clin Nutr 2000; 71:1003-7.
14) Kamath AB, Wang L, Das H, Li L, Reinhold VN, Bukowski JF. Antigens in tea-beverage prime human Vgamma 2Vdelta 2 T cells in vitro and in vivo for memory and nonmemory antibacterial cytokine responses. Proc Natl Acad Sci USA 2003 May 13;100(10):6009-14.
15) Popkin BM, Armstrong LE, Bray GM, Caballero B, Frei B, Willett WC. A new proposed guidance system for beverage consumption in the United States. Am J Clin Nutr. 2006 Mar; 83(3): 529-42.
16) Hakim IA, Alsaif MA, Alduwaihy M, Al-Rubeaan K, Al-Nuaim AR, Al-Attas OS. Tea consumption and the prevalence of coronary heart disease in Saudi adults: results from a Saudi national study. Prev Med 2003;36(1):64-70.
17) Sesso HD, Gaziano JM, Buring JE, Hennekens CH. Coffee and tea intake and the risk of myocardial infarction. Am J Epidemiol 1999; 149:162-7.
18) Mukamal KJ, Maclure M, Muller JE, Sherwood JB, Mittleman MA. Tea Consumption and Mortality After Acute Myocardial Infarction. Circulation 2002; 105:2476.
19) Geleijnse JM, Launer LJ, Van der Kuip DA, HofmanA, Witteman JC. Inverse association of tea and flavonoid intakes with incident myocardial infarction: the Rotterdam Study. Am J Clin Nutr. 2002 May; 75(5): 880-6.
20) Peters U, Poole C, Arab L. Does tea affect cardiovascular disease? A meta-analysis. Am J Epidemiol 2001; 154(6): 495-503.
21) Kuriyama S, Shimazu T, Ohmori K, Kikuchi N, Nakaya N, Nishino Y, Tsubono Y, Tsuji I. Green tea consumption and mortality due to cardiovascular disease, cancer, and all causes in Japan: the Ohsaki study. JAMA. 2006 Sep 13; 296(10): 1255-65.
22) Davies MJ, Judd JT, Baer DJ, Clevidence BA, Paul DR, Edwards AJ, Wiseman SA, Muesing RA, Chen SC. Black tea consumption reduces total and LDL cholesterol in mildly hypercholesterolemic adults. J Nutr. 2003 Oct; 133(10): 3298S-3302S.
23) Vermeer MA, Mulder TP, Molhuizen HO. Theaflavins from black tea, especially theaflavin-3-gallate, reduce the incorporation of cholesterol into mixed micelles. J Agric Food Chem. 2008 Dec 24; 56(24): 12031-6.
24) Geleijnse JM, Launer LJ, Hofman A, Pols HAP, Witteman JCM. Tea flavonoids may protect against atherosclerosis: the Rotterdam Study. Arch Intern Med 1999; 159:2170-4.
25) Duffy SJ, Keaney JF Jr, Holbrook M, Gokce N, Swerdloff PL, Frei B, Vita JA. Short- and long-term black tea consumption reverses endothelial dysfunction in patients with coronary artery disease. Circulation 2001; 104:151-6.
26) Hodgson JM, Puddey IB, Burke V, Watts GF, Beilin LJ. Regular ingestion of black tea improves brachial artery vasodilator function. Clin Sci 2002; 102(2):195-201.
27) Hofmann CS, Sonenshein GE, Green tea polyphenol epigallocatechin-3 gallate induces apoptosis of proliferating vascular smooth muscle cells via activation of p53. FASEB J. 2003 Apr; 17(6): 702-4. Epub 2003 Feb 05.
28) Ishikawa T, Suzukawa M, Ito T, Yoshida H, Ayaori M, Nishiwaki M, Yonemura A, Hara Y, Nakamura H. Effect of tea flavonoid supplementation on the susceptibility of low-density lipoprotein to oxidative modification. Am J Clin Nutr 1997; 66:261-6.
29) Vinson JA, Dabbagh YA, Serry MM, Jang J. Plant flavonoids, especially tea flavonols, are powerful antioxidants using an in vitro oxidation model for heart disease. J Agric Food Chem 1995; 43:2800-2.
30) Hirata K, Shimada K, Watanabe H, Otsuka R, Tokai K, Yoshiyama M, Homma S, Yoshikawa J. Black tea increases coronary flow velocity reserve in healthy male subjects. Am J Cardiol. 2004 Jun 1; 93(11): 1384-8, A6.
31) Vinson JA, Teufel K, Wu N. Green and black teas inhibit atherosclerosis by lipid, antioxidant, and fibrinolytic mechanisms. J Agric Food Chem. 2004 Jun 2; 52(11): 3661-5.
32) Yang YC, Lu FH, Wu JS, Wu CH, Chang CJ. The protective effect of habitual tea consumption on hypertension. Arch Intern Med. 2004 Jul 26; 164(14): 1534-40.
33) Hakim IA, Chow HHS, Harris RB. Green tea consumption is associated with decreased DNA damage among GSTM1 positive smokers regardless of their hOGG1 genotype. J Nutr. 2008; 138:1567S–71S.
34) Hakim IA, Harris RB, Brown S, Chow HH, Wiseman S, Agarwal S, Talbot W. Effect of increased tea consumption on oxidative DNA damage among smokers: a randomized controlled study. J Nutr. 2003 Oct; 133(10): 3303S-3309S.
35) Roy M, Chakrabarty S, Sinha D, Bhattacharya RK, Siddiqi M. Anticlastogenic, antigenotoxic and apoptotic activity of epigallocatechin gallate: a green tea polyphenol. Mutat Res 2003; 523-524:33-41.
36) Bhattacharyya A, Mandal D, Lahiry L, Sa G, Das T. Black tea protects immunocytes from tumor-induced apoptosis by changing Bcl-2/Bax ratio. Cancer Lett. 2004 Jun 25; 209(2): 147-54.
37) Dora I, Arab L, Martinchik A, Sdvizhkov A, Urbanovich L, Weisgerber U. Black tea consumption and risk of rectal cancer in Moscow population. Ann Epidemiol. 2003 Jul; 13(6): 405-11.
38) Su LJ, Arab L. Tea consumption and the reduced risk of colon cancer — results from a national prospective cohort study. Public Health Nutr. 2002 Jun; 5(3): 419-25.
39) Arts IC, Jacobs DR Jr, Gross M, Harnack LJ, Folsom AR. Dietary catechins and cancer incidence among postmenopausal women: the Iowa Women’s Health Study (United States). Cancer Causes Control. 2002 May; 13(4): 373-82.
40) Zheng W, Doyle TJ, Kushi LH, et al. Tea consumption and cancer incidence in a prospective cohort study of postmenopausal women. Am J Epidemiol 1996; 144:175-81.
41) Sun CL, Yuan JM, Lee MJ, Yang CS, Gao YT, Ross RK, Yu MC. Urinary tea polyphenols in relation to gastric and esophageal cancers: a prospective study of men in Shanghai, China. Carcinogenesis 2002; 23(9): 1497-1503.
42) Ji BT, Chow WH, Hsing AW, McLaughlin JK, Dai Q, Gao YT, Blot WJ, Fraumeni JF Jr. \Green tea consumption and the risk of pancreatic and colorectal cancers. Int J Cancer. 1997 Jan 27; 70(3): 255-8.
43) Ohishi T, Kishimoto Y, Miura N, Shiota G, Kohri T, Hara Y, Hasegawa J, Isemura M. Synergistic effects of (-)-epigallocatechin gallate with sulindac against colon carcinogenesis of rats treated with azoxymethane. Cancer Lett. 2002 Mar 8; 177(1): 49-56.
44) Lodovici M, Casalini C, De Filippo C, Copeland E, Xu X, Clifford M, Dolara P. Inhibition of 1,2-dimethylhydrazine-induced oxidative DNA damage in rat colon mucosa by black tea complex polyphenols. Food Chem Toxicol. 2000 Dec; 38(12): 1085-8.
45) Isemura M, Saeki K, Kimura T, Hayakawa S, Minami T, Sazuka M. Tea catechins and related polyphenols as anti-cancer agents. Biofactors. 2000; 13(1-4): 81-5.
46) Kuo PL, Lin CC. Green Tea constituent (-)-epigallocatechin-3-gallate inhibits Hep G2 cell proliferation and induces apoptosis through p53-dependent and Fas-mediated pathways. J Biomed Sci 2003; 10(2): 219-27.
47) Issa AY, Volate SR, et al. Green tea selectively targets initial stages of intestinal carcinogenesis in the AOM-ApcMin mouse model. Carcinogenesis. 2007 Jul 17; [Epub ahead of print]
48) Siddiqui IA, Saleem M. et al. Tea beverage in chemoprevention and chemotherapy of prostate cancer. Acta Pharmacol Sin. 2007 Sep; 28(9): 1392-408.
49) Hakim IA, Harris RB. Joint effects of citrus peel use and black tea intake on the risk of squamous cell carcinoma of the skin. BMC Dermatol. 2001; 1(1): 3. Epub 2001 Aug 01.
50) Hakim IA, Harris RB, Weisgerber UM. Tea intake and squamous cell carcinoma of the skin: influence of type of tea beverages. Cancer Epidemiol Biomarkers Prev. 2000 Jul;9(7):727-31.
51) Lu YP, Lou YR, Lin Y, Shih WJ, Huang MT, Yang CS, Conney AH. Inhibitory effects of orally administered green tea, black tea, and caffeine on skin carcinogenesis in mice previously treated with ultraviolet B light (high-risk mice): relationship to decreased tissue fat. Cancer Res 2001 Jul 1; 61(13): 5002-9.
52) Ahmad N, Mukhtar H. Cutaneous photochemoprotection by green tea: a brief review. Skin Pharmacol Appl Skin Physiol. 2001 Mar-Apr; 14(2): 69-76.
53) Katiyar SK, Bergamo BM, Vyalil PK, Elmets CA. Green tea polyphenols: DNA photodamage and photoimmunology. J Photochem Photobiol B. 2001 Dec 31; 65(2-3): 109-14.
54) Katiyar SK, Perez A, Mukhtar H. Green tea polyphenol treatment to human skin prevents formation of ultraviolet light B-induced pyrimidine dimers in DNA. Clin Cancer Res. 2000 Oct; 6(10): 3864-9.Tea and Health Research Overview/p.12
55) Conney AH, Lu Y-P, Lou Y-R, Xie J-G, Huang M-T. Inhibitory effect of green and black tea on tumor growth. Proc Soc Exp Biol Med 1999; 220:229-33.
56) Li N, Zheng S, Han C, Chen J. The Chemoprotective Effects of Tea on Human Oral Precancerous Mucosa Lesions. Proc Soc Exp Biol Med 1999; 220:218-24.
57) Li N, Chen X, Liao J, Yang G, Wang S, Josephson Y, Han C, Chen J, Huang MT, Yang CS. Inhibition of 7,12-dimethylbenz [a]anthracene (DMBA)-induced oral carcinogenesis in hamsters by tea and curcumin. Carcinogenesis 2002; 23(8): 1307-13.
58) Arts ICW. A review of the epidemiological evidence on tea, flavonoids, and lung cancer. J Nutr. 2008; 138:1561S–6S.
59) Yang G, Liu Z, Seril DN, et al. Black tea constituents, theaflavins, inhibit 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK0-induced lung tumorigenesis in A/J mice. Carcinogenesis 1997; 18:2361-5.
60) Yang G, Wang Z-Y, Kim S, et al. Characterization of early pulmonary hyperproliferation and tumor progression and their inhibition by black tea in a 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced lung tumorigenesis model with A/J mice. Cancer Res 1997; 57:1889-94.
61) Ganguly C, Saha P, Panda CK, Das S. Inhibition of Growth, Induction of Apoptosis and Alteration of Gene Expression by Tea Polyphenols in the Highly Metastatic Human Lung Cancer Cell Line NCI-H460. Asian Pac J Cancer Prev. 2005 Jul-Sep; 6(3): 326-31.
62) Zhang M, Binns CW, Lee AH. Tea consumption and ovarian cancer risk: a case-control study in China. Cancer Epidemiol Biomarkers Prev 2002; 11(8): 713-8.
63) Larsson SC, Wolk A. Tea consumption and ovarian cancer risk in a population-based cohort. Arch Intern Med. 2005 Dec 12-26; 165(22): 2683-6.
64) Kumar N, Titus-Ernstoff L, Newcomb PA, Trentham-Dietz A, Anic G, Egan KM. Tea consumption and risk of breast cancer. Cancer Epidemiolog Biomarkers Prev. 2009 Jan; 18(1): 341-5.
65) Kelly SP, Gomez-Ramirez M, Montesi JL, Foxe JJ. L-Theanine and caffeine in combination affect human cognition as evidenced by oscillatory alpha-band activity and attention task performance. J Nutr. 2008; 138:1572S–7S.
66) Egashira N, Ishigami N, et al. Theanine prevents memory impairment induced by repeated cerebral ischemia in rates. Phytother Res. 2007 Aug 17; [Epub ahead of print]
67) Mandel SA, Amit T, Kalfon L, Reznichenko L, Youdim MBH. Targeting multiple neurodegenerative diseases etiologies with multimodal-acting green tea catechins. J Nutr. 2008; 138:1578S–83S.
68) Rezai-Zadeh K, Shytle D, Sun N, Mori T, Hou H, Jeanniton D, Ehrhart J, Townsend K, Zeng J, Morgan D, Hardy J, Town T, Tan J. Green tea epigallocatechin-3-gallate (EGCG) modulates amyloid precursor protein cleavage and reduces cerebral amyloidosis in Alzheimer transgenic mice. J Neurosci. 2005 Sep 21; 25(38): 8807-14.
69) Hu G, Bidel S, et al. Coffee and tea consumption and the risk of Parkinson’s disease. Mov Disord. 2007 Aug 21: [Epub ahead of print]
70) Dulloo AG, Duret C, Rohrer D, Girardier L, Mensi N, Fathi M, Chantre P, Vandermander J. 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.
71) Chantre P, Lairon D. Recent findings of green tea extract AR25 (Exolise) and its activity for the treatment of obesity. Phytomedicine 2002; 9(1): 3-8.
72) Venables MC, Hulston CJ, Cox HR, and Jeukendrup AE. Green tea extract ingestion, fat oxidation, and glucose tolerance in healthy humans. Am J Clin Nutr 2008; 87(3): 778-84.
73) Nagao T, Hase T and Tokimitsu I. A green tea extract high in catechins reduces body fat and cardiovascular risk in humans. Obesity. 2007 Jun; 15:1473-83.
74) Nagao T, Komine Y, Soga S, Meguro S, Hase T, Tanaka Y, Yokimitsu I. Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men. Am J Clin Nutr. 2005 Jan; 81(1): 122-9.
75) Murase T, Nagasawa A, Suzuki J, Hase T, Tokimitsu I. Beneficial effects of tea catechins on diet-induced obesity: stimulation of lipid catabolism in the liver. Int J Obes Relat Metab Disord 2002;26(11):1459-64.
76) Murase T, Haramizu S, Shimotoyodome A, Tokimitsu I. Reduction of diet-induced obesity by a combination of tea-catechin intake and regular swimming. Int J Obesity 2005 Oct:1-8.
77) Shimotoyodome A, Haramizu S, Inaba M, Murase T, Tokimitsu I. Exercise and green tea extract stimulate fat oxidation and prevent obesity in mice. Med Sci Sports Exerc. 2005 Nov; 37(11): 1884-92.
78) 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. Renumber to 61
79) Stote KS, Baer DJ. Tea consumption may improve biomarkers of insulin sensitivity and risk factors for diabetes. J Nutr. 2008; 138:1584S–8S.
80) Anderson RA, Polansky MM. Tea enhances insulin activity. J Agric Food Chem 2002; 50(24): 7182-6.
81) Kamath AB, Wang L, Das H, Li L, Reinhold VN, Bukowski JF. Antigens in tea-beverage prime human Vgamma 2Vdelta 2 T cells in vitro and in vivo for memory and nonmemory antibacterial cytokine responses. Proc Natl Acad Sci U S A. 2003 May 13; 100(10): 6009-14. Epub 2003 Apr 28.
82) Sarkar, S., Sett, P., Chowdhury, T., and Ganguly, D.K. Effect of black tea on teeth. J Indian Soc Pedod Prev Dent 2000; 18:139-140.
83) Yu, H., Oho, T., Xu, L. X. Effects of several tea components on acid resistance of human tooth enamel. J Dent 1995; 13:101-105.
84) Linke HA, LeGeros RZ. Black tea extract and dental caries formation in hamsters. Int J Food Sci Nutr 2003; 54(1): 89-95.
85) Bassiouny MA, Kuroda S, Yang J. 2008. Topographic and radiographic profile assessment of dental erosion. Part III: Effect of green and black tea on human dentition. General Dentistry. Jul-Aug; 56(5): 451-61.
86) Kushiyama M, Shimazaki Y, Murakami M, Yamashita Y. 2009. Relationship between intake of green tea and periodontal disease. J Periodontol. Mar; 80(3): 372-7.
87) Curhan GC, Willett WC, Speizer FE, Stampfer MJ. Beverage use and risk of kidney stones in women. Ann Intern Med 1998; 128:534-40.
88) Curhan GC, Willett WC, Rimm EB, Spiegelman D, Stampfer MJ. Prospective study of beverage use and the risk of kidney stones. Am J Epidemiol 1996; 143:240-7.
89) Hegarty VM, May HM, Khaw K-T. Tea drinking and bone mineral density in older women. Am J Clin Nutr 2000; 71:1003-7.
90) Wu CH, Yang YC, Yao WJ, Lu FH, Wu JS, Chang CJ. Epidemiological evidence of increased bone mineral density in habitual tea drinkers. Arch Intern Med. 2002 May 13; 162(9): 1001-6.
91) Devine A, Hodgson JM, Dick IM, Prince RL. Tea drinking is associated with benefits on bone density in older women. Am J Clin Nutr. 2007; 86(4) 1243-7.Tea and Health Research Overview/p.14
92) Lloyd T, Rollings NJ, Kieselhorst K, Eggli DF, Mauger E. Dietary caffeine in DC. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000; 19:256-61