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Camellia sinensis (green & black tea)

Both green & black tea are derived from Camellia sinensis. Green tea is simply dried. Black tea is processed to achieve different properties. Adverse effects: - tea extracts containing large amounts of catechins may be hepatotoxic - hot or burning hot tea daily + smoking increases risk of esophageal cancer 56% [27] - hot or burning hot tea daily + > 1 alcoholic beverage/day increases risk of eosphageal cancer 2-fold - hot or burning hot tea daily + smoking & drinking increases risk of esophageal cancer 5 fold [27] Drug interactions: - catechins* inhibit organic anion transporting polypeptides - catechins in green tea increase levels of simvastatin & decrease levels of rosuvastatin [30] - green tea probably is best avoided in patients already taking statins [30] * constituent of green tea Mechanism of action: 1) constituents a) catechins (flavan-3-ols) (-)-epigallocatechin-3-gallate (EGCG) - much higher in green tea than black tea [21] b) polyphenols - polyphenon E c) caffeine: - black tea 25-48 mg/cup (8 oz); green tea 25-29 mg [28] 2) effects a) anticarcinogenic properties (experimental models) - skin, lung, oral, esophagus, stomach, colon, pancreas, breast [12] - green tea may provide prophylaxis for prostate cancer [16] - no benefit for prevention of colorectal carcinoma [19] - green tea without benefit for prevention of breast cancer [20] b) cardiovascular benefits 1] diminishes total cholesterol [9] 2] no effect on serum triglycerides or HDL cholesterol 3] antiplatelet activity [14] 4] diminishes mortality (see Ohsaki study) [17] 5] >= 1 cup of green or black tea/day reduces cardiovascular risk (RR=0.7) [24] 6] green tea, but not black tea may reduce risk for coronary artery disease [25] 7] regular tea drinking >= 1 cup/day is associated with slower progression of coronary artery calcium & a reduction in cardiovascular events [26] c) antioxidant effects 1] may attenuate oxidation of LDL [10] 2] may attenuate beta-amyloid-induced neurotoxicity [11] 3] inhibits MPTP induced dopaminergic neurodegeneration [15] d) increases 24 hour energy expenditure [7] e) antiviral properties [8] f) inhibits fatty acid synthase [13] g) may reduce incidence of dementia - 1-6 cups of tea/day may reduce risk of Alzheimer's disease 16-19% & reduce risk of vascular dementia 25-29% [29] h) both green & black tea (>= 2 cups/day) lower all-cause mortality [31] i) green tea may be protective against leukocyte telomere shortening [32]

Interactions

drug interactions

Related

Ohsaki National Health Insurance Cohort study

General

pharmaceutical herb; medicinal herb; herbal supplement; botanical beverage

References

  1. Wang E et al Biochem, Biophys Res Commun 297:412, 2002
  2. Gupta SK et al, Ophthalmic Res 34:258 2002
  3. Chen PC et al, Inflammation 26:233, 2002
  4. Kinjo J et al, Biol Pharm Bull 25:1238, 2002
  5. Gupta et al, Mutation Res 512:37, 2002
  6. Skizydlewska E et al, Phytomedicine 9:232, 2002
  7. Bell SJ & Goodrick GK, Crit Rev Food Sci Nutr 42:163, 2002
  8. Fassina B et al, AIDS 16:939, 2002
  9. Tokunaga S et al, Ann Epidemiol 12:157, 2002
  10. Kasaoka S et al, J Nutr Biochem 13:96, 2002
  11. Choi YT et al Lif Sci 70:603, 2002
  12. Yang CS et al, Annu Rev Pharmacol Toxicol 42:25, 2002
  13. Wang X & Tian W, Biochem Biophys Res Commun 288:1200, 2001
  14. Kang WS et al, J Cardiovac Pharmacol 38:875, 2001
  15. Levites Y et al, J Neurochem 78:1072, 2001
  16. Prescriber's Letter 13(11): 2006 Health Benefits of Drinking Green Tea Detail-Document#: 221109 (subscription needed) http://www.prescribersletter.com
  17. Medline Plus Green tea prevents prostate cancer http://www.nlm.nih.gov/medlineplus/news/fullstory_24219.html
  18. Kuriyama S et al, Green tea consumption and mortality due to cardiovascular disease, cancer and all causes in Japan. The Ohsaka Study. JAMA 2006, 296:1255 PMID: 16968850
  19. Sun CL et al Green tea, black tea and colorectal cancer risk: a meta-analysis of epidemiologic studies. Carcinogenesis. 2006 Jul;27(7):1310-5. Epub 2005 Nov 25. PMID: 16311246
  20. Michels KB et al Diet and breast cancer: a review of the prospective observational studies. Cancer. 2007 Jun 15;109(12 Suppl):2712-49. Review. PMID: 17503428
  21. Physician's First Watch, Dec 23, 2013 David G. Fairchild, MD, MPH, Editor-in-Chief Massachusetts Medical Society http://www.jwatch.org - O'Connor A Spike in Harm to Liver Is Tied to Dietary Aids. New York Times. Dec 21, 2013 http://www.nytimes.com/2013/12/22/us/spike-in-harm-to-liver-is-tied-to-dietary-aids.html?_r=0
  22. Prescriber's Letter 21(3): 2014 (subscription needed) http://www.prescribersletter.com
  23. Clement Y. Can green tea do that? A literature review of the clinical evidence. Prev Med. 2009 Aug-Sep;49(2-3):83-7. Review. PMID: 19465043
  24. Hand L Moderate Tea Drinking Tea May Slow CAC Progression, Cut CV Event Risk: MESA. Medscape. Sep 23, 2016 http://www.medscape.com/viewarticle/869038
  25. Barclay L Green, but not black, tea may reduce risk for CAD. Medscape. Jan 28, 2011 http://www.medscape.com/viewarticle/790815
  26. Miller PE, Zhao D, Frazier-Wood AC et al. Associations of coffee, tea, and caffeine intake with coronary artery calcification and cardiovascular events. Am J Med 2017 Feb; 130:188 PMID: 27640739 http://www.amjmed.com/article/S0002-9343(16)30925-1/abstract
  27. Yu C, Tang H, Guo Y et al Effect of Hot Tea Consumption and Its Interactions With Alcohol and Tobacco Use on the Risk for Esophageal Cancer: A Population-Based Cohort Study. Ann Intern Med. 2018. Feb 6. PMID: 29404576 http://annals.org/aim/article-abstract/2671921/effect-hot-tea-consumption-its-interactions-alcohol-tobacco-use-risk - Kamangar F, Freedman ND Hot Tea and Esophageal Cancer. Ann Intern Med. 2018. Feb 6. PMID: 29404600 http://annals.org/aim/article-abstract/2671922/hot-tea-esophageal-cancer
  28. Mayo Clinic Caffeine content for coffee, tea, soda and more https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/caffeine/art-20049372
  29. Hu HY, Wu BS, Ou YN et al Tea consumption and risk of incident dementia: A prospective cohort study of 377,392 UK Biobank participants. Transl Psychiatry, 2022, 12, 171 PMID: 35474192 PMCID: PMC9042826 Free PMC article
  30. Geriatric Review Syllabus, 11th edition (GRS11) Harper GM, Lyons WL, Potter JF (eds) American Geriatrics Society, 2022
  31. Worcester S Drinking Tea Linked to Health Benefits, Lower Risk of Dying. Medscape August 29, 2022 https://www.medscape.com/viewarticle/979925 - Inoue-Choi M, Ramirez Y, Cornelis MC et al Tea Consumption and All-Cause and Cause-Specific Mortality in the UK Biobank. A Prospective Cohort Study. Annals of Internal Medicine. 2022. August 30 PMID: 36037472 https://www.acpjournals.org/doi/10.7326/M22-0041
  32. Sohn I, Shin C, Baik I Associations of green tea, coffee, and soft drink consumption with longitudinal changes in leukocyte telomere length. Scientific Reports. 2023. 13:492 PMID: 36627320 PMCID: PMC9832020 Free PMC article https://www.nature.com/articles/s41598-022-26186-y

Component-of

camellia sinensis/eucalyptus oil

Components

caffeine (NoDoz, Vivarin) kunecatechins (Veregen)