Diet & Nutrition

Put a Kettle On: Research Shows Green Tea Is Great for Your Gut

Put A Kettle On: Research Shows Green Tea Is Great For Your Gut

There’s nothing like a steamy cup of green tea to help you feel both relaxed and rejuvenated. And almost everyone knows that green tea is great for your overall health. But recent research goes a step further, revealing that some of the remarkable benefits of green tea actually impact us on a microbial level!

So put a kettle on—it’s time to discover all the wonderful things green tea can do for you and your gut.

Why Drink Green Tea?

In addition to tasting absolutely lovely, green tea naturally contains a nice variety of health promoting chemical compounds including saponins, chlorophyll, fluorine, GABA, polyphenols (such as catechins, theaflavins, tannins, and flavonoids), as well as the amino acid theanine, and numerous vitamins, minerals, and antioxidants. So it’s not surprising that drinking green tea is associated with wellness in many ways, including:

• Cardiovascular health: Green tea consumption has been shown to help support healthy cholesterol levels and blood flow.1,2

• Positive mood: That cup of green tea can produce a feeling of calm relaxation and happiness, and may help lift you out of the blues.3,4,5

• Healthy cognitive function: The compounds in green tea encourage alertness, concentration, and good memory function—while helping you retain brain power as you get older.5,6,7

• Sun protection: Although not a substitute for taking sensible sun precautions such as using sunscreen and covering up, green tea consumption my help your body better handle the UV exposure it receives.8

• Strong bones: Drinking green tea regularly has a protective effect on aging bones.9

• Cellular health: Research shows green tea and its compounds can help keep the body healthy all the way down to its cells.10,11,12

• Optimum blood sugar levels: Enjoying green tea encourages blood sugar levels to stay in a healthier range.13

• Healthy weight: The catechins in green tea may make it easier to avoid excess pounds.14,15

• Comfy digestion: Catechins may help soothe temporary inflammation and other tummy troubles.16

Green tea may even be an effective way to keep the grim reaper at bay! A large study following 40,000 people between the ages of 40 and 79 for 11 years found that those who drank five or more cups of green tea daily had a significantly lower risk of dying from any cause than those who drank less than one cup daily.17

Antimicrobial Properties of Green Tea

When used topically, green tea seems to be surprisingly effective at zeroing in and going after the types of bacteria, fungi, yeast, and other microbes we don’t want in our bodies. Studies show external use of green tea can be effective in clearing up many microbially-induced skin breakouts, irritations, and flare ups on the face, body, genitals, and feet.18,19,20,21,22,23

If you’ve been struggling with less than perfect dental checkups, it turns out green tea also works well as a cleansing mouth rinse. Even a solution as weak as 2% supports oral health by keeping biofilm in check.24,25 And drinking green tea further benefits your mouth by boosting the antibacterial properties of saliva.26

The antimicrobial characteristics of green tea even seem to have the potential to support urinary wellness, and as little as a single cup daily may be able to clear the urinary tract of unfriendly bacteria.27,28

If Green Tea Is Antimicrobial, Won’t It Harm My Microbiome?

Hang on a sec—maintaining a healthy microbiome that contains lots of friendly probiotics is absolutely essential for good health! So at this moment you’re probably wondering how green tea could possibly be good for you if it acts antimicrobially in and on your body. Wouldn’t it stand to reason that drinking and rinsing with green tea, soaking your feet in it, or applying it to your skin would wreak havoc with your gut, skin, and oral microbial environments?

Actually, one of the most exciting things about green tea is that its antimicrobial activities appear to be highly selective—so it goes after undesirable organisms, while leaving beneficial flora unscathed! A number of studies have been undertaken to determine how green tea affects the gut, and the results either showed no harmful change, or that microbial composition was significantly improved with increased numbers of desirable species, including Bifidobacteria and Lactobacillus.29,30,31

One important reason green tea may help boost probiotic numbers (in addition to antimicrobial selectivity) is that it turns out to be an effective prebiotic—providing the perfect nutrition for your good bacteria to thrive.30,31 The bottom line? Green tea lets you enjoy the best of both worlds—supporting the good guys in your microbial community, while giving unwanted party crashers the boot.

Which Green Tea Is Best?

If you’re a green tea novice, relax, because this habit can be simple, soothing, and delicious. Just look for any organic variety with a brand name that you trust, and try a few different options to see which you like best. You may also want to explore fermented teas (such as kombucha) to introduce your gut to lots of new probiotic friends. If you prefer bagged tea to loose leaf, just make sure the bags are made from natural materials that haven’t been treated or bleached with dangerous chemicals. Green tea retains its healthy properties regardless of temperature, so feel free to serve it hot or iced.

If you’re up for a little more adventure, try replacing your morning coffee with a homemade almond milk matcha latte (make sure it’s ceremonial grade). Once you get a taste for this delicacy and the sustained energy it gives you, you’ll be a connoisseur in the making.

To further support your health—and your amazing microbiome—you may also want to supplement with a high quality, time-released probiotic such as PRO-15, and take the prebiotic properties of your green tea up a notch by stirring in some organic prebiotic powder.

Green tea is a delicious way to enhance your physical, emotional, and mental well-being. So whichever way you enjoy it, when you pour yourself a big mug or glass, you’re literally drinking to your health!


1. Zheng, X., Xu, Y., Li, S., Liu, X., Hui, R., & Huang, X. (2011). Green tea intake lowers fasting serum total and LDL cholesterol in adults: a meta-analysis of 14 randomized controlled trials. American Journal of Clinical Nutrition, 94(2), 601-610. doi:10.3945/ajcn.110.010926

2. Kokubo, Y., Iso, H., Saito, I., Yamagishi, K., Yatsuya, H., Ishihara, J., … Tsugane, S. (2013). The Impact of Green Tea and Coffee Consumption on the Reduced Risk of Stroke Incidence in Japanese Population: The Japan Public Health Center-Based Study Cohort. Stroke, 44(5), 1369-1374. doi:10.1161/strokeaha.111.677500

3. Lardner, A. L. (2013). Neurobiological effects of the green tea constituent theanine and its potential role in the treatment of psychiatric and neurodegenerative disorders. Nutritional Neuroscience, 17(4), 145-155. doi:10.1179/1476830513y.0000000079

4.Juneja, L. (1999). L-theanine—a unique amino acid of green tea and its relaxation effect in humans. Trends in Food Science & Technology, 10(6-7), 199-204. doi:10.1016/s0924-2244(99)00044-8

5. C Dietz et al. (2017). Effect of Green Tea Phytochemicals on Mood and Cognition - Journals - NCBI. Retrieved from

6. Kuriyama S, Hozawa A, Ohmori K, et al. (2006). Green tea consumption and cognitive function: a cross-sectional study from the Tsurugaya Project 1. Am J Clin Nutr, 83(2):355-61.

7. Schmidt, A., Hammann, F., Wölnerhanssen, B., Meyer-Gerspach, A. C., Drewe, J., Beglinger, C., & Borgwardt, S. (2014). Green tea extract enhances parieto-frontal connectivity during working memory processing. Psychopharmacology, 231(19), 3879-3888. doi:10.1007/s00213-014-3526-1

8. Record, I. R., & Dreosti, I. E. (1998). Protection by black tea and green tea against UVB and UVA+B induced skin cancer in hairless mice. Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, 422(1), 191-199. doi:10.1016/s0027-5107(98)00192-4

9. Shen, C., Yeh, J. K., Cao, J. J., & Wang, J. (2009). Green tea and bone metabolism. Nutrition Research, 29(7), 437-456. doi:10.1016/j.nutres.2009.06.008

10. Choan, E., Segal, R., Jonker, D., Malone, S., Reaume, N., Eapen, L., & Gallant, V. (2005). A prospective clinical trial of green tea for hormone refractory prostate cancer: An evaluation of the complementary/alternative therapy approach. Urologic Oncology: Seminars and Original Investigations, 23(2), 108-113. doi:10.1016/j.urolonc.2004.10.008

11. Gao, Y. T., McLaughlin, J. K., Blot, W. J., Ji, B. T., Dai, Q., & Fraumeni, J. F. (1994). Reduced Risk of Esophageal Cancer Associated With Green Tea Consumption. JNCI Journal of the National Cancer Institute, 86(11), 855-858. doi:10.1093/jnci/86.11.855

12. Imai, K., Suga, K., & Nakachi, K. (1997). Cancer-Preventive Effects of Drinking Green Tea among a Japanese Population. Preventive Medicine, 26(6), 769-775. doi:10.1006/pmed.1997.0242

13. Iso, H., Date, C., Wakai, K., Fukui, M., & Tamakoshi, A. (2006). The Relationship between Green Tea and Total Caffeine Intake and Risk for Self-Reported Type 2 Diabetes among Japanese Adults. Annals of Internal Medicine, 144(8), 554. doi:10.7326/0003-4819-144-8-200604180-00005

14. Seo, D., Jeong, H. W., Cho, D., Lee, B. J., Lee, J. H., Choi, J. Y., … Lee, S. (2015). Fermented Green Tea Extract Alleviates Obesity and Related Complications and Alters Gut Microbiota Composition in Diet-Induced Obese Mice. Journal of Medicinal Food, 18(5), 549-556. doi:10.1089/jmf.2014.3265

15. Wang, L., Zeng, B., Zhang, X., Liao, Z., Gu, L., Liu, Z., … Fang, X. (2016). The effect of green tea polyphenols on gut microbial diversity and fat deposition in C57BL/6J HFA mice. Food Funct, 7(12), 4956-4966. doi:10.1039/c6fo01150k

16. Fan, F., Sang, L., & Jiang, M. (2017). Catechins and Their Therapeutic Benefits to Inflammatory Bowel Disease. Molecules, 22(3), 484. doi:10.3390/molecules22030484

17. Kuriyama, S., Shimazu, T., Ohmori, K., Kikuchi, N., Nakaya, N., Nishino, Y., … Tsuji, I. (2006). Green Tea Consumption and Mortality Due to Cardiovascular Disease, Cancer, and All Causes in Japan. JAMA, 296(10), 1255. doi:10.1001/jama.296.10.1255

18. Tuong, W., Walker, L., & Sivamani, R. K. (2014). Polyphenols as novel treatment options for dermatological diseases: A systematic review of clinical trials. Journal of Dermatological Treatment, 26(4), 381-388. doi:10.3109/09546634.2014.991675

19. Isaacs, C. E., Wen, G. Y., Xu, W., Jia, J. H., Rohan, L., Corbo, C., … Hillier, S. (2008). Epigallocatechin Gallate Inactivates Clinical Isolates of Herpes Simplex Virus. Antimicrobial Agents and Chemotherapy, 52(3), 962-970. doi:10.1128/aac.00825-07

20. Hsu, S., Dickinson, D., Borke, J., Walsh, D. S., Wood, J., Qin, H., … Bollag, W. B. (2007). Green tea polyphenol induces caspase 14 in epidermal keratinocytes via MAPK pathways and reduces psoriasiform lesions in the flaky skin mouse model. Experimental Dermatology, 16(8), 678-684. doi:10.1111/j.1600-0625.2007.00585.x

21. Ikeda, S., Kanoya, Y., & Nagata, S. (2013). Effects of a foot bath containing green tea polyphenols on interdigital tinea pedis. The Foot, 23(2-3), 58-62. doi:10.1016/j.foot.2013.01.001

22. Elsaie ML, Abdelhamid MF, Elsaaiee LT, Emam HM. (2009). The efficacy of topical 2% green tea lotion in mild-to-moderate acne vulgaris. J Drugs Dermatol, 8(4):358-64.

23. Sharquie, K. E., AL-Turfi, I. A., & AL-Salloum, S. M. (2000). The Antibacterial Activity of TeaIn vitroandIn vivo(In Patients with Impetigo Contagiosa). The Journal of Dermatology, 27(11), 706-710. doi:10.1111/j.1346-8138.2000.tb02263.x

24. Sarin S, Marya C, Nagpal R, Oberoi SS, Rekhi A. (2015). Preliminary Clinical Evidence of the Antiplaque, Antigingivitis Efficacy of a Mouthwash Containing 2% Green Tea - A Randomised Clinical Trial. Oral Health Prev Dent, 13(3):197-203.

25. Antunes, D. P., Salvia, A. C., De Araújo, R. M., Di Nicoló, R., Koga Ito, C. Y., & De Araujo, M. A. (2014). Effect of green tea extract and mouthwash without alcohol on Candida albicansbiofilm on acrylic resin. Gerodontology, 32(4), 291-295. doi:10.1111/ger.12132

26. Lin, S., Li, C., Suzuki, K., Chang, C., Chou, K., & Fang, S. (2014). Green Tea Consumption after Intense Taekwondo Training Enhances Salivary Defense Factors and Antibacterial Capacity. PLoS ONE, 9(1), e87580. doi:10.1371/journal.pone.0087580

27. Noormandi, A., & Dabaghzadeh, F. (2015). Effects of green tea on Escherichia coli as a uropathogen. Journal of Traditional and Complementary Medicine, 5(1), 15-20. doi:10.1016/j.jtcme.2014.10.005

28. Reygaert, W., & Jusufi, I. (2013). Green tea as an effective antimicrobial for urinary tract infections caused by Escherichia coli. Frontiers in Microbiology, 4. doi:10.3389/fmicb.2013.00162

29. Cardona, F., Andrés-Lacueva, C., Tulipani, S., Tinahones, F. J., & Queipo-Ortuño, M. I. (2013). Benefits of polyphenols on gut microbiota and implications in human health. The Journal of Nutritional Biochemistry, 24(8), 1415-1422. doi:10.1016/j.jnutbio.2013.05.001 Benefits of polyphenols on gut microbiota and implications in human health

30. Lee, H. C., Jenner, A. M., Low, C. S., & Lee, Y. K. (2006). Effect of tea phenolics and their aromatic fecal bacterial metabolites on intestinal microbiota. Research in Microbiology, 157(9), 876-884. doi:10.1016/j.resmic.2006.07.004

31. Jin, J., Touyama, M., Hisada, T., & Benno, Y. (2012). Effects of green tea consumption on human fecal microbiota with special reference to Bifidobacterium species. Microbiology and Immunology, 56(11), 729-739. doi:10.1111/j.1348-0421.2012.00502.x


Roberta Pescow is a writer at Hyperbiotics and proud mom of two amazing and unique young men. Natural wellness is a subject she’s passionate about, so she loves sharing information that helps others discover all the ways probiotics support glowing health and well-being. To learn more about how a healthy microbiome can enrich your life, subscribe to our newsletter.