Tea Health

Health Benefits

According to legend, in the year 2737 B.C. Shen Nung was boiling some hot water while he rested under a wild tea tree. Some tea leaves dropped into his pot, and tea was discovered! Since then, tea has been enjoyed for it's flavor, aroma, and medicinal properties. Click on one of the following links to read some medical abstract summaries on the health benefits of tea!

(Please note that the medical information contained in this website is for educational purposes only. Consult your physician for treatment of any health problem.)

Drinking tea can help prevent cancer!

1. Green Tea (camellia sinensis) extract and its possible role in the prevention of cancer.
"The American Cancer Society estimates that in the 1980s more than 4.5 million Americans died of cancer. ... With cancer being the second most common cause of death in the United States population, the possibility that readily-available natural substances may be beneficial in the prevention of cancer warrants closer examination. A growing body of research has demonstrated green tea polyphenols to be powerful antioxidants with anticarcinogenic properties."
by Brown MD.

Sage Health Clinic, Bend, OR, USA.
Altern Med Rev 1999 Oct;4(5): 360-370

2. Green tea and cancer chemoprevention.
"Worldwide interest in green tea as a cancer preventive agent for humans has increased, because it is non-toxic and it is effective in a wide range of organs. ... All the results suggest that consumption of green tea is a practical and effective cancer preventive both before cancer onset and after cancer treatment."

by Suganuma M, Okabe S, Sueoka E, Satsuyama S, Imai K, Nakachi K, Fujiki H.
Saitama Cancer Center Research Institute, Saitama, Japan.
Mutat Res 1999 Jul 16;428(1-2):339-44.

3. Prostate cancer chemoprevention by green tea.
"Prostate Cancer (PCA) is one of the most invasive cancers and the second leading cause of cancer-related deaths among males in the United States. ... Many laboratory experiments conducted in cell culture systems and in animal models have shown the usefulness of green tea, and the polyphenols present therein, against PCA. The epidemiological basis for this possiblity is twofold. First, some epidemiological observations have suggested that people who consume tea regularly have a lower risk of PCA-related deaths. Second, the incidence of PCA in China, a population that consumes green tea on a regular basis, is lowest in the world."

by Gupta S, Ahmad N, Mukhtar H.
Dept of Dermatology, University Hospitals of Cleveland, Case Western Reserve University, OH, USA.
Semin Urol Oncol 1999 May;17(2):70-6

4. Influence of drinking tea on breast cancer malignancy among Japanese patients.
"Our results indicate that increased consumption of green tea prior to clinical cancer onset is significantly associated with improved prognosis of stage I and II breast cancer, and this association may be related to a modifying effect of green tea on the clinical characteristics of the cancer."

by Nakachi K, Suemasu K, Takeo T, Imai K, Higashi Y.
Saitama Cancer Center Research Institute.
Jpn J Cancer Res 1998 Mar:89(3):254-61

5. Chemopreventive effects of tea extracts and various components on human pancreatic and prostate tumor cells in vitro.
"Pancreatic and prostate cancers pose serious problems to human health. To determine the potential for chemopreventive intervention against pancreatic and prostate cancers, black and green tea extracts and components of these extracts were examined in vitro for their effect on tumor cell growth. ... This study suggests that components from black and green tea extracts can modulate the expression of genes known to play a role in the carcinogenesis process and, therefore, may be potential agents for chemoprevention against pancreatic cancer."

by Lyn-Cook BD, Rogers T, Yan Y, Blann EB, Kadlubarr FF, Hammons GJ
Div of Molecular Epidemiology, National Center for Toxicological Research, Jefferson, AR, USA
Nutr Cancer 1999;35(1):80-6

6. Protection by black tea and green tea against UVB and UVA + B induced skin cancer in hairless mice.
"The effects of green and black tea consumption on the early indices of UVB and UVA + B skin damage in hairless mice have been studied in the absence of any chemical tumour initiators or promoters. ... This study confirms earlier reports that tea consumption can reduce the incidence of skin cancer in hairless mice, and indicates that black tea may afford more protection against simulated solar irradiation than green tea."

by Record IR, Dreosti IE
CSIRO Div of Human Nutrition, Adelaide, South Australia, Australia
Mutat Res 1998 Nov 9;422(1):191-9

Drinking tea can help protect against heart disease!

1. Tea Flavonoids May Protect Against Atherosclerosis - The Rotterdam Study
"Epidemiological studies have reported a reduced risk of coronary heart disease in subjects with a high flavonoid intake. ... Tea is the major dietary source for flavonoids in the Western populations. ... We investigated the association of aortic atherosclerosis, a strong indicator of cardiovascular risk, with intake of tea in 3454 participants of the population based Rotterdam Study. ... Conclusion: This study indicates a protective effect of tea drinking against ischemic heart disease."

by Johanna M. Gelijnse, PhD; Lenore J. Launer, PhD; Albert Hofman, M.D.; Huibert A. P. Pols, M.D.; Jacqueline C. M. Witterman, PhD
Arch Intern Med. 1999;159:2170-2174

2. Flavonoid intake and coronary mortality in Finland: a cohort study.
"OBJECTIVE: To study the association between dietary intake of flavonoids and subsequent coronary mortality. ... SUBJECTS: 5133 Finnish men and women aged 30-69 years and free from heart disease at baseline. ... CONCLUSIONS: The results suggest that people with very low intakes of flavonoids have higher risks of coronary disease."

by Knekt P, Jarvinen R, Reunanen A, Maatela J
National Public Health Institute, Helsinki, Finland
BMJ 1996 Feb 24:312(7029):478-81

3. Inhibitory effect of Chinese green tea on endothelial cell-induced LDL oxidation.
"The results of this study demonstrated that Lung Chen (Long Jing) Tea and catechin-rich fractions significantly prevented endothelial cell induced LDL oxidation. The consumption of Lung Chen Tea may therefore lower the risk of coronary heart diseases."

by Yang TT, Koo MW
Dept of Pharmacology, Faculty of Medicine, The University of Hong Kong, Hong Kong.
Atherosclerosis 2000 Jan;148(1):67-73

4. Dietary antioxidant flavonoids and risk of coronary heart disease: the Zutphen Elderly Study.
"Flavonoids are polyphenolic antioxidants naturally present in vegetables, fruits, and beverages such as tea and wine. ... We then assessed the flavonoid intake of 805 men aged 65-84 years in 1985 by a cross-check dietary history; the men were then followed up for 5 years. ... Flavonoids in regularly consumed foods may reduce the risk of death from coronary heart disease in elderly men."

by Hertog MG, Feskens EJ, Hollman PC, Katan MB, Kromhout D
National Institute of Public Health, Bilthoven, Netherlands
Lancet 1993 Oct 23;342(8878):1007-11

Drinking tea can help lower cholesterol!

1. Hypocholesterolemic (cholesterol lowering) effects of Chinese tea.
"Chinese teas with different degrees of fermentation were examined for their effect on diet-induced hypercholesterolemia in rats. The teas tested were Chinese Green tea, Jasmine, Iron Buddha, Oolong, and Pu-erh. ... Chinese Green tea and Jasmine tea, both with a minimum degree of fermentation, were found to have significant serum and liver cholesterol lowering effects."

by Yang TT, Koo MW
Dept of Pharmacology, Faculty of Medicine, University of Hong Kong, Hong Kong
Pharmacol Res 1997 Jun;35(6):505-12

2. Tea consumption. relationship to cholesterol, blood pressure, and coronary and total mortality.
"BACKGROUND AND METHODS. The relation of tea to cholesterol, systolic blood pressure, and mortality from coronary heart disease and all causes was studied in 9,856 men and 10,233 women without history of cardiovascular disease or diabetes. All men and women 35-49 years of age from the country of Oppland (Norway) were invited to participate; the attendance rate was 90%. RESULTS: Mean serum cholesterol decreased with increasing tea consumption."

by Stensvold I, Tverdal A, Solvoll K, Foss OP
National Health Screening Service, Oslo, Norway
Prev Med 1992 Jul;21(4):546-53

3. Effect of black tea polyphenols on plasma lipids in cholesterol-fed rats.
"The influence of black tea polyphenols on plasma lipid levels was investigated in rats fed a 15% lard and 1% cholesterol diet. The diet was supplemented with 1% black tea polyphenols extracted and condensed from black tea. ... The supplementation of black tea polyphenols in this lard-cholesterol diet decreased the lipid levels in the plasma and increased the fecal excretion of total lipids and cholesterol. ... These results suggest that a high dose of black tea polyphenols exerts a hypocholesterolemic (cholesterol lowering) effect in cholesterol-fed rats."

by Matsumoto N, Okushio K, Hara Y
Food Research Laboratories, Mitsui Norin Co., Shizuoka, Japan.
J Nutr Sci Vitaminol (Tokyo) 1998 Apr;44(2):337-42

Drinking tea can help boost energy and oxidize fat!

1. Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans.
"BACKGROUND: Current interest in the role of functional foods in weight control has focused on plant ingredients capable of interfering with the sympathoadrenal system. OBJECTIVE: We investigated whether a green tea extract...could increase 24-h energy expenditure (EE) and fat oxidation in humans. ... CONCLUSIONS: Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se. The green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation, or both."

by Dulloo AG, Duret C, Rohrer D, Girardier L, Mensi N, Fathi M, Chantre P, Vandermander J
Dept of Physiology, Faculty of Medicine, University of Geneva
Am J Clin Nurt 1999 Dec:70(6):1040-5

Drinking tea can help you lose weight!

1. Anti-obesity action of oolong tea
"OBJECTIVE: Oolong tea is traditionally reported to have anti-obesity and hypolipidaemic effects. The present study was performed to clarify whether oolong tea prevented obesity induced in mice by the oral administration of a high-fat diet for 10 weeks. ... CONCLUSION: The results suggest that oolong tea may be an effective crude drug for the treatment of obesity and fatty liver caused by a high-fat diet."

by Han LK, Takaku T, Li J, Kimura Y, Okuda H
2nd Dept of Medical Biochemistry, School of Medicine, Ehime University, Japan
Int J Obes Relat Metab Disord 1999 Jan;23(1):98-105

Drinking tea can help aid digestion!

Modulation of intestinal functions by food substances.
"The small intestinal epithelium plays a crucial role in the digestion/modification of food components, absorption of nutrients and recognition of food-derived signals. ... In this paper, the effects of various food substances on the intestinal functions, particularly the absorption functions, are discussed. ... Substances which could suppress the activity of intestinal glucose transporters, for example, can be expected to reduce the dietary glucose uptake in the intestinal epithelium and control the blood glucose level. Polyphenolic compounds from plants, including green tea, were found to have such activity."

by Shimizu M
University of Tokyo, Graduate School of Agricultural and Life Sciences, Dept of Applied Biological Chemistry, Japan
Nahrung 1999 Jun;43(3):154-8

Drinking tea can help reduce dental plaque!

1. Reduction of dental plaque deposition in humans by oolong tea extract.
"The inhibitory effect of oolong tea extract (OTE) containing polymerized polyphenols on plaque deposition was examined in 35 human volunteers. ... OTE was found to significantly inhibit plaque deposition in volunteers."

by Ooshima T, Minami T, Aono W, Tamura Y, Hamada S
Dept of Pedodontics, Osaka University, Faculty of Dentistry, Japan
Caries Res 1994;28(3):146-9