Unlike most antiviral drugs, green tea appears to work by boosting the immune system to combat diseases such as genital warts (caused by HPV) and the flu (caused by the influenza virus).
Benefits of Green Tea for Boosting Antiviral Immune Function
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
“The belief of green tea as a ‘wonder weapon’ against diseases dates back thousands of years.” I’ve talked about it in relation to chronic disease, but what about infectious disease? Interest in the antimicrobial activity of tea dates back to a military medical journal in 1906, suggesting that servicemen fill their canteens with tea to kill off the bugs that caused typhoid fever. However, this effect of tea was not studied further until the late 1980s, when tea compounds were pitted against viruses and bacteria in test tubes and petri dishes.
But, what we care about is do they work in people? I had dismissed this entire field of inquiry as clinically irrelevant—until genital warts. “External genital warts,” caused by human wart viruses, “are one of the most common and fastest-spreading venereal diseases worldwide.”
“Patients with [external genital warts] present with one or several cauliflower-like growths on the genitals and/or anal regions,” considerably impairing people’s “emotional and sexual well-being.” But, rub some green tea ointment on, and you can achieve “complete clearance of all warts” in more than 50% of cases.
Wow. If it works so well for wart viruses, what about flu viruses? Works great in a petri dish, but what about in people? Tea-drinking schoolchildren do seem to be protected. But, you don’t know until it’s put to the test. If you give healthcare workers green tea compounds, they come down with the flu about three times less often than those given placebo. In fact, just gargling with green tea may help. While a similar effect was not found in high school students, gargling with green tea may drop the risk of influenza infection seven- or eight-fold, compared to gargling with water, in elderly nursing home residents, where flu can get really serious.
Unlike antiviral drugs, green tea appears to help by boosting the immune system, enhancing the proliferation and activity of gamma delta T cells, a type of immune cell that acts as “a first-line defense against infection.” “Subjects who drank six cups of tea per day had up to a 15-fold increase in [infection-fighting] interferon…production in as little as one week”—but why?
There’s actually a molecular pattern shared by cancer cells and pathogens with “edible plant products, such as tea, apples, mushrooms, and wine.” And so, eating healthy foods may help maintain our immune cells on ready alert, effectively priming our gamma delta T cells “that then can provide natural resistance to microbial infections, and perhaps tumors.”
I guess I shouldn’t have been so surprised—tea, after all, is “a vegetable infusion.” You’re basically drinking a hot water extraction of a dark green leafy vegetable.
Please consider volunteering to help out on the site.
- Gupta AK, Daigle D. Sinecatechins 10% ointment: a green tea extract for the treatment of external genital warts. Skin Therapy Lett. 2015 Jan-Feb;20(1):6-8.
- Reygaert WC. The antimicrobial possibilities of green tea. Front Microbiol. 2014 Aug 20;5:434.
- Yiannakopoulou ECh. Recent patents on antibacterial, antifungal and antiviral properties of tea. Recent Pat Antiinfect Drug Discov. 2012 Apr;7(1):60-5.
- McNaught JG, Maj. On the Action of Cold or Lukewarm Tea on Bacillus Typhosus. Royal Army Medical Corps.
- Steinmann J, Buer J, Pietschmann T, Steinmann E. Anti-infective properties of epigallocatechin-3-gallate (EGCG), a component of green tea. Br J Pharmacol. 2013 Mar;168(5):1059-73.
- Ide K, Yamada H, Matsushita K, Ito M, Nojiri K, Toyoizumi K, Matsumoto K, Sameshima Y. Effects of green tea gargling on the prevention of influenza infection in high school students: a randomized controlled study. PLoS One. 2014 May 16;9(5):e96373.
- Yamada H, Takuma N, Daimon T, Hara Y. Gargling with tea catechin extracts for the prevention of influenza infection in elderly nursing home residents: a prospective clinical study. J Altern Complement Med. 2006 Sep;12(7):669-72.
- Zink A, Traidl-Hoffmann C. Green tea in dermatology--myths and facts. J Dtsch Dermatol Ges. 2015 Aug;13(8):768-75.
- Matsumoto K, Yamada H, Takuma N, Niino H, Sagesaka YM. Effects of green tea catechins and theanine on preventing influenza infection among healthcare workers: a randomized controlled trial. BMC Complement Altern Med. 2011 Feb 21;11:15.
- Park M, Yamada H, Matsushita K, Kaji S, Goto T, Okada Y, Kosuge K, Kitagawa T. Green tea consumption is inversely associated with the incidence of influenza infection among schoolchildren in a tea plantation area of Japan. J Nutr. 2011 Oct;141(10):1862-70.
- Song JM, Lee KH, Seong BL. Antiviral effect of catechins in green tea on influenza virus. Antiviral Res. 2005 Nov;68(2):66-74.
- Rowe CA, Nantz MP, Bukowski JF, Percival SS. Specific formulation of Camellia sinensis prevents cold and flu symptoms and enhances gamma,delta T cell function: a randomized, double-blind, placebo-controlled study. J Am Coll Nutr. 2007 Oct;26(5):445-52.
- 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.
Image credit: gadost0 via pixabay. Image has been modified.
Video credit: Tyler McReynolds, Teetotalin LLC.
Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.
“The belief of green tea as a ‘wonder weapon’ against diseases dates back thousands of years.” I’ve talked about it in relation to chronic disease, but what about infectious disease? Interest in the antimicrobial activity of tea dates back to a military medical journal in 1906, suggesting that servicemen fill their canteens with tea to kill off the bugs that caused typhoid fever. However, this effect of tea was not studied further until the late 1980s, when tea compounds were pitted against viruses and bacteria in test tubes and petri dishes.
But, what we care about is do they work in people? I had dismissed this entire field of inquiry as clinically irrelevant—until genital warts. “External genital warts,” caused by human wart viruses, “are one of the most common and fastest-spreading venereal diseases worldwide.”
“Patients with [external genital warts] present with one or several cauliflower-like growths on the genitals and/or anal regions,” considerably impairing people’s “emotional and sexual well-being.” But, rub some green tea ointment on, and you can achieve “complete clearance of all warts” in more than 50% of cases.
Wow. If it works so well for wart viruses, what about flu viruses? Works great in a petri dish, but what about in people? Tea-drinking schoolchildren do seem to be protected. But, you don’t know until it’s put to the test. If you give healthcare workers green tea compounds, they come down with the flu about three times less often than those given placebo. In fact, just gargling with green tea may help. While a similar effect was not found in high school students, gargling with green tea may drop the risk of influenza infection seven- or eight-fold, compared to gargling with water, in elderly nursing home residents, where flu can get really serious.
Unlike antiviral drugs, green tea appears to help by boosting the immune system, enhancing the proliferation and activity of gamma delta T cells, a type of immune cell that acts as “a first-line defense against infection.” “Subjects who drank six cups of tea per day had up to a 15-fold increase in [infection-fighting] interferon…production in as little as one week”—but why?
There’s actually a molecular pattern shared by cancer cells and pathogens with “edible plant products, such as tea, apples, mushrooms, and wine.” And so, eating healthy foods may help maintain our immune cells on ready alert, effectively priming our gamma delta T cells “that then can provide natural resistance to microbial infections, and perhaps tumors.”
I guess I shouldn’t have been so surprised—tea, after all, is “a vegetable infusion.” You’re basically drinking a hot water extraction of a dark green leafy vegetable.
Please consider volunteering to help out on the site.
- Gupta AK, Daigle D. Sinecatechins 10% ointment: a green tea extract for the treatment of external genital warts. Skin Therapy Lett. 2015 Jan-Feb;20(1):6-8.
- Reygaert WC. The antimicrobial possibilities of green tea. Front Microbiol. 2014 Aug 20;5:434.
- Yiannakopoulou ECh. Recent patents on antibacterial, antifungal and antiviral properties of tea. Recent Pat Antiinfect Drug Discov. 2012 Apr;7(1):60-5.
- McNaught JG, Maj. On the Action of Cold or Lukewarm Tea on Bacillus Typhosus. Royal Army Medical Corps.
- Steinmann J, Buer J, Pietschmann T, Steinmann E. Anti-infective properties of epigallocatechin-3-gallate (EGCG), a component of green tea. Br J Pharmacol. 2013 Mar;168(5):1059-73.
- Ide K, Yamada H, Matsushita K, Ito M, Nojiri K, Toyoizumi K, Matsumoto K, Sameshima Y. Effects of green tea gargling on the prevention of influenza infection in high school students: a randomized controlled study. PLoS One. 2014 May 16;9(5):e96373.
- Yamada H, Takuma N, Daimon T, Hara Y. Gargling with tea catechin extracts for the prevention of influenza infection in elderly nursing home residents: a prospective clinical study. J Altern Complement Med. 2006 Sep;12(7):669-72.
- Zink A, Traidl-Hoffmann C. Green tea in dermatology--myths and facts. J Dtsch Dermatol Ges. 2015 Aug;13(8):768-75.
- Matsumoto K, Yamada H, Takuma N, Niino H, Sagesaka YM. Effects of green tea catechins and theanine on preventing influenza infection among healthcare workers: a randomized controlled trial. BMC Complement Altern Med. 2011 Feb 21;11:15.
- Park M, Yamada H, Matsushita K, Kaji S, Goto T, Okada Y, Kosuge K, Kitagawa T. Green tea consumption is inversely associated with the incidence of influenza infection among schoolchildren in a tea plantation area of Japan. J Nutr. 2011 Oct;141(10):1862-70.
- Song JM, Lee KH, Seong BL. Antiviral effect of catechins in green tea on influenza virus. Antiviral Res. 2005 Nov;68(2):66-74.
- Rowe CA, Nantz MP, Bukowski JF, Percival SS. Specific formulation of Camellia sinensis prevents cold and flu symptoms and enhances gamma,delta T cell function: a randomized, double-blind, placebo-controlled study. J Am Coll Nutr. 2007 Oct;26(5):445-52.
- 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.
Image credit: gadost0 via pixabay. Image has been modified.
Video credit: Tyler McReynolds, Teetotalin LLC.
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Benefits of Green Tea for Boosting Antiviral Immune Function
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Content URLDoctor's Note
For more on what green tea can (and cannot) do, check out videos such as:
- Tea and Artery Function
- Preventing Prostate Cancer with Green Tea
- Treating Prostate Cancer with Green Tea
- Can Green Tea Help Prevent Cancer?
- Can Green Tea Help Treat Cancer?
- Natural Treatment for Acne and Fungal Infections
For all our videos on the latest research on green tea, visit our Green Tea topic page.
How else can we improve our immune function? See, for example:
- Using the Produce Aisle to Boost Immune Function
- Preserving Athlete Immunity with Chlorella
- Preserving Immune Function in Athletes with Nutritional Yeast
- Kiwifruit for the Common Cold
- How to Boost Your Immune System with Wakame Seaweed
- Best Food to Prevent Common Childhood Infections
- Best Food to Counter Stress-Induced Immune Suppression
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