Bioavailability and Efficiency of Ten Catechins as an Antioxidant

  • Shi, John (Food Research Center, Agriculture and Agri-Food Canada, Guelph)
  • Published : 2002.09.01


Tea is a pleasant, popular and safe beverage in the world. During the past decade, epidemiological studies have shown that tea catechins intake is associated with lower risk of cardiovascular disease. Tea provides a dietary source of health-promoting components to help humans reduce a wide variety of cancer risks and chronic diseases. The antioxidative activity of tea-derived catchins has been extensively studied. The antioxidant effect is a synergistic action between catechins e.g. EGCG, EGC, ECG, EC, pheophytins a and b, and other components in tea leaves, which aye more bioavailable for human body. Green tea has a Higher content of catechins than other kinds of tea. Green tea extract with hot water has high potential and more efficiency to reduce cancer risk than any other tea products or pure EGCG. Protein, iyon, and other food components may interfere with the bioavailability of ten catechins. Interaction of catechins with drug affects the cancer-preventive activity of some cancer-fighting medication. Further studies are required to determine the bioavailability of tea catechins and cancer-preventive functionality.


  1. Bushman JL. 1998. Green tea and cancer in humans: a review of the literature. Nutr and Cancer 31: 151-159
  2. Mukhtar H, Katiya SK, Agarwal R. 1994. Green tea and skin- anticarcinogenic effect. J Invest Dermatol 102: 3-7
  3. Kuroda Y, Hara Y. 1999. Antimutagenic and anticarcinogenic activity of tea polyphenols. Mutat Res 436: 67-97
  4. Wiseman SA, Balentine DA, Frei B. 1997. Antioxidants in tea. Crit Rev Food Sci Nutri 37: 705-718
  5. Bell JRC, Donovan JL, Wong R, Waterhouse AL, German JB, Walzem RL, Kasim-Karakas SE. 2000. (+)-Catechin in human plasma after ingestion of a single serving of reconstituted red wine. Am J Clin Nutr 71: 103-108
  6. Chen L, Lee MJ, Li H, Yang CS. 1997. Absorption, distribution, and elimination of tea polyphenols in rats. Drug Metabolism and Disposition 25: 1045-1050
  7. Balentine DA, Wiseman SA, Bouwens LCM. 1997. The chemistry of tea flavonoids. Crit Rev Food Sci Nutr 37: 693-704
  8. Suganuma M, Okabe S, Kai Y, Sueoka N, Sueoka E, Fujiki H. 1999. Synergistic effect of (-)-epigallocatechin gallate with (-)-epicatechin, Sulindac or Tamoxifen on cancer-preventive activity in the human lung cancer cell line PC-9. Cancer Research 59: 44-47
  9. Chen ZP, Schell JB, Ho CT, Chen KY. 1998. Green tea epigallocatechin gallate shows a pronounced growth inhibitory effect on cancerous cells but not on their normal counterparts. Cancer Lett 129: 173-179
  10. Higashi-Okai K, Taniguchi M, Okai Y. 2000. Potent antioxidative activity of non-polyphenolic fraction of green tea (camellia sinensis) association with pheophytins a and b. J Sci Food Agric 80: 117-120<117::AID-JSFA499>3.0.CO;2-8
  11. Arets ICW, Hollman PCH, Feskens EJM, Bueno de Mesquita HB, Krombout D. 2001. Catechin intake and associated dietary and lifestyle factors in a representative sample of Dutch men and women. European J Clini Nutri 55: 76-81
  12. Pietta PG, Simonetti P. 1998. Dietary flavonoids and iteraction with endogenous antioxidant. Biochem Molec Biol Int 44: 1069-1074
  13. Bendich A, Shapiro S. 1986. Effect of $\beta$-carotene and canthaxanthin on the immune responses of the rats. J Nutr 116: 2254-2262
  14. Haslam E. 1996. Natural polyphenols and vegetable tanning as drugs: possible modes of action. J Nat Prod 59: 205-215
  15. Disler PB, Lynch SR, Torrance JD, Sayers MH, Bothwell TH, Charlton RW. 1975. The mechanism of the inhibition of iron absorption by tea. S Afr J Med Sci 40: 109-116
  16. Samman S, Sandstrom B, Toft M, Bukhave K, Jensen M, Sorensen S, Hansen M. 2001. Green tea or rosemary extract added to foods reduces nonheme-iron absorption. Am J Clin Nutri 73: 607-612
  17. South PK, William MS, House A. 1997. Tea consumption does not affect iron absorption in rats unless tea and iron are consumed together. Nutri Res 8: 1303-1310