Research reveals a fascinating story with an amazing dichotomy.
Dr. SiegelTea, the beverage made from the leaves of the plant Camellia sinensis, is consumed by 158 million Americans every day.2 Green tea is made by taking freshly picked C. sinensis leaves and rapidly heating them to avoid wilting and oxidation. Some combination of wilting, oxidizing and fermenting can lead to white, oolong, black and post-fermented tea variations.3 In all preparations, the exact method of growing (terroir plays a role) is what leads to the great abundance of tea varieties we all love, hot or cold.
But what about its effects on the skin? This a fascinating story, with an amazing dichotomy. Let us begin on the drug side. Drug, you say? Caffeine is what you might be thinking, and that’s certainly a component of tea. However, caffeine is not the compound that brought a FDA-approved green tea sludge product to market. That drug, Sinecatechins Ointment, (Veregen, Fougera), is novel. Unlike virtually every other drug FDA approves that is a single molecule or an enantiomer, this product is an ointment containing 15% sinecatechins, a brown-green aqueous extract of C. sinensis that is used to treat genital warts.
Sinecatechins extract is not a single active chemical; rather, it is a soup with many potential beneficial ingredients. Sinecatechins extract is composed mostly of catechins, a great part of which is epigallocatechin gallate.4 There has been some serious research on epigallocatechin gallate and its utility in treating HPV-related disease.5,6 The manufacturer of Sinecatechins Ointment shows data from their trials claiming complete clearance of external genital and perianal warts in most patients (53.6% vs. 35.3% for vehicle), with a high rate (93.2%) of sustained clearance at 12 weeks for patients who achieve complete clearance (vs. 94.2% for vehicle).7 Sinecatechins ointment is another tool in our armamentarium. Unfortunately, a 30g tube8 sells more than $1,000, which could lead the creative physician to wonder if you could do as well, for a lot less money, with a tea concentrate made for drinking!9
Next: Hype versus evidence
More from Irregular Border:
On the other hand, we are seeing lots of green tea extracts in a variety of cosmetics and cosmeceuticals. Are they doing anything? Unequivocally, maybe. A study at SUNY Downstate Medical Center showed that in vitro suppression of IgE production by green tea extract was not mediated by apoptosis.10 The authors also demonstrated that a green tea extract has immunoregulatory effects on human IgE responses in vitro. Further work by the same group demonstrated that antioxidants green tea polyphenols (GTPs) and caffeine, alone and in combination, modulate hydrogen peroxide-induced upregulation of reactive oxygen species free radicals and lipid peroxidation byproducts, including 4-hydroxy-2-nonenal (HNE) in normal human skin fibroblast WS-1 cells in vitro. GTPs and caffeine were selected for evaluation because these compounds demonstrated antioxidative properties in various skin models. Using a flow cytometry-based assay, the authors demonstrated that, at 0.001% concentration, green tea polyphenols alone, and in combination with 0.1 mM caffeine, inhibited the upregulation of H2O2-generated free radicals and HNE in human skin fibroblasts in vitro while caffeine alone demonstrated limited anti-oxidant properties.11
Further efforts supported these observations12 and, building on this serious bench work, the translation to clinical utility was demonstrated in rosacea, where a unique combination of antioxidants including resveratrol, green tea polyphenols, and caffeine was found to reduce facial redness.
In that study, facial redness was evaluated by trained dermatologists and dermatology residents looking at clinical photographs and spectrally enhanced images of the subjects. All 16 of 16 clinical images showed improvement and 13 of 16 spectrally enhanced images were improved by 6 weeks. Adverse effects were not observed in any subject.
The benefits on intact, non-damaged skin are still being elucidated and there is a lot of hype. There is soft literature on green tea in acne13 and other disease, but much of the work is still preliminary. Googling “green tea cream” brings up approximately 23 million hits. Following those to look at products shows that, while some products have high concentrations of green tea extracts,14 others appear to use “angel dusting,”15 where the active agent concentration is low on the ingredient list and may have little or no biological effect.
Commercially available tea bags, green or black, have long been used to treat a puffy eye appearance or tired-looking eyes, despite a lack of peer reviewed data, where it competes in this space with cucumber and potato slices.16 Of course, green tea, like many plants, can be a source of tannins, which can be used as a soak or poultice, just like grandma showed you. And if you brew up some tea and don’t care to drink it, you can always use it as a mouthwash to treat your dental plaque and gingivitis.17
Enjoy that cuppa!
Disclosures: Dr. Siegel reports no relevant disclosures.
4. Scheinfeld, Noah. (2013). Update on the treatment of genital warts. Dermatology Online Journal, 19(6). doj_18559. Retrieved from: http://escholarship.org/uc/item/42v5g88n
5. Drug Discov Today. 2016 Feb;21(2):333-41. doi: 10.1016/j.drudis.2015.10.019. Epub 2015 Nov 4. Natural polyphenols: potential in the prevention of sexually transmitted viral infections. Date AA(1), Destache CJ(2). PMID: 26546859 [PubMed - in process]
6. Garcia FA, Cornelison T, Nuño T, et al. Results of a phase II randomized, double-blind, placebo-controlled trial of Polyphenon E in women with persistent high-risk HPV infection and low-grade cervical intraepithelial neoplasia. Gynecol Oncol. 2014;132(2):377-82.
9. http://www.groundgreentea.com/content/decaffeinated-green-tea-powder and http://www.amazon.com/Hard-Rhino-Green-Extract-Powder/dp/B006M0HNMK
10. Hassanain E, Silverberg JI, Norowitz KB, Chice S, Bluth MH, Brody N, Joks R, Durkin HG, Smith-Norowitz TA. Green tea (Camelia sinensis) suppresses B cell production of IgE without inducing apoptosis. Ann Clin Lab Sci. 2010 Spring;40(2):135-43. PubMed PMID: 20421624 available as full text online at http://www.annclinlabsci.org/content/40/2/135.long
11. Jagdeo J, Brody N. Complementary antioxidant function of caffeine and green tea polyphenols in normal human skin fibroblasts. J Drugs Dermatol. 2011 Jul;10(7):753-61. PubMed PMID: 21720657. Online at http://jddonline.com/articles/dermatology/S1545961611P0753X/1
12. Silverberg JI, Jagdeo J, Patel M, Siegel D, Brody N. Green tea extract protects human skin fibroblasts from reactive oxygen species induced necrosis. J Drugs Dermatol. 2011 Oct;10(10):1096-101. PubMed PMID: 21968658. Online at http://jddonline.com/articles/dermatology/S1545961611P1096X/2
13. Li Z, Summanen PH, Downes J, Corbett K, Komoriya T, Henning SM, Kim J, Finegold SM. Antimicrobial Activity of Pomegranate and Green Tea Extract on Propionibacterium Acnes, Propionibacterium Granulosum, Staphylococcus Aureus and Staphylococcus Epidermidis. J Drugs Dermatol. 2015 Jun;14(6):574-8. PubMed PMID: 26091382. Online at http://jddonline.com/articles/dermatology/S1545961615P0574X
14. http://topixpharm.com/product/power-of-three-cream-w-resveratrol/ checked 4/8/16.
17. Radafshar G, Ghotbizadeh M, Saadat F, Mirfarhadi N. Effects of green tea (Camellia sinensis) mouthwash containing 1% tannin on dental plaque and chronic gingivitis: a double-blinded, randomized, controlled trial. J Investig Clin Dent. 2015 Aug 14. doi: 10.1111/jicd.12184. [Epub ahead of print] PubMed PMID: 26272266.