Can Green Tea Help Fight Off Viral and Bacterial Infections?

by Sugimoto Tea Company
Health, Wellness

While green tea isn’t a cure for viruses and bacterial infections, there are several studies that show it can help prevent certain illnesses. Here’s a breakdown of each study and what they have to say on green tea and its antiviral and antibacterial properties.

Guide Contents:

  • Viral vs Bacterial Infections
  • Can Green Tea Help Protect Against Viral and Bacterial Infections?
  • FACT CHECK: Green Tea and COVID-19
  • Green Tea Against Viruses

    Antiviral and Antibacterial Properties of Green Tea | 5 Ways Green Tea Can Help Fight Off Disease-Causing Viruses and Bacteria

    Viral vs Bacterial Infections

    One of the most basic distinctions is what causes the infection. Viral infections are caused by viruses, bacterial infections are caused by bacteria.

    According to Mayo Clinic, here are the other differences between the two:

    • Treatment — Antibiotics are usually effective for bacteria, but they can’t kill viruses.
    • Conditions Required for Survival — Bacteria can survive in different types of environments, with some able to withstand extreme temperatures. There are also certain types of bacteria that are beneficial to humans, such as those that live in the intestines and aid with digestion. Unlike bacteria, viruses require a living organism to stay alive- although COVID-19 findings are showing that viruses can live on surfaces for a number of hours.
    • Diseases They Cause
      • Some diseases caused by bacterial infections include Tuberculosis (caused by the Mycobacterium tuberculosis bacterium), Urinary Tract Infection (caused by certain gastrointestinal bacteria, such as Escherichia coli), and Strep throat (caused by the Streptococcus pyogenes bacteria).
      • On the other hand, diseases caused by viral infections include AIDS (caused by the human immunodeficiency virus or HIV), Common colds (typically caused by rhinoviruses), and Chickenpox (caused by the varicella-zoster virus).
      • Some ailments or disorders, like diarrhea, meningitis, and pneumonia, can be caused by either a virus or bacterium.

    Can Green Tea Help Protect Against Viral and Bacterial Infections?

    Several studies have confirmed that green tea has antiviral and antibacterial properties, which they’ve linked to *catechins, particularly Epigallocatechin-3-gallate (EGCG). EGCG is prevalent in green tea, making up approximately 59% of the catechins in green tea leaves. (Note: For Sugimoto teas, the highest amounts of EGCG can be found in our Organic Ceremonial Matcha, at 50%, and our Organic Culinary Matcha, at 40%.)

    *What are catechins? Catechins are a group of compounds present in different plants that have various health benefits, such as decreasing the risk of infection for certain diseases, improving blood circulation, and lowering blood sugar.

    FACT CHECK: Green Tea And COVID-19

    Green Tea as a Cure for COVID-19

    Amidst the COVID-19 crisis, a post circulated on Facebook about Chinese doctor Li Wenliang allegedly recommending methylxanthine, theobromine, and theophylline (which are typically found in green tea) as a cure for the coronavirus.

    However, according to AFP Fact Check, there’s no evidence to support this claim. According to their interview with Dr. Jayaruwan Bandara, director of the Sri Lanka Medical Research Institute, drinking tea isn’t recognized as a treatment or a way to protect oneself from COVID-19.

    While green tea isn’t a recognized cure for COVID-19, some researchers are looking into the possibility that one of its components, EGCG, can help fight off COVID-19. In one study, researchers tested how certain compounds that have shown antiviral properties will interact with COVID-19 proteins. Among the 18 compounds tested, EGCG showed the most potential as a drug treatment for the new coronavirus.

    Green Tea Against Viruses


    1. EGCG May Help Prevent Hepatitis-C Infection

    Several studies [1, 2, 3] have looked into how ECGC can potentiallyprevent someone from getting infected by Hepatitis-C by preventing the virus from attaching to target cells. With further research, this could open up a new way of looking at Hepatitis-C prevention for those who suffer from chronic Hepatitis-C and for preventing re-infection for patients who just went through a liver transplant.

    2. ECGC Disrupts Certain Processes in the Life Cycle of HIV-1

    Several studies have shown that EGCG prevents certain processes in the HIV-1 life cycle. For instance, EGCG may inhibit the ligand gp120 [4, 5]. This prevents the virus from attaching to the CD4 T cells, which is a crucial process in HIV infection.

    However, the researchers acknowledge that further studies are needed to confirm the potential that EGCG can be used for antiretroviral therapy.

    3. Clinical Trials Show That EGCG May Help Protect Against Influenza

    Studies also show that EGCG can help protect against Influenza (flu):

  • Several *in-vitro studies [6, 7, 8] have been done to discover the possibility of EGCG inhibiting Influenza viruses, which can prevent infection.
  • Similarly, in one *in-vivo study [9] wherein participants were asked to consume tea catechins, results showed that catechins have a “statistically significant preventive effect” against Influenza.
  • One study showed that tea catechins can help reverse the methicillin-resistant properties of MRSA [10].
  • EGCG has also been shown to increase the effectiveness of antibiotics like methicillin and benzylpenicillin against MRSA [11].
  • In one study, researchers discovered that EGCG can boost the antibacterial effects of the antibiotic amoxicillin against *H. pylori [12].
  • Another study discovered that at certain concentrations, EGCG can prevent the growth of **E. coli [13].
  • *What is in-vivo? In-vivo refers to medical tests, studies, or research done within a living organism. This is the opposite of in-vitro, which is done outside of the living organism (e.g. in a test tube or petri dish)

    Green Tea Against Bacteria

    4. Green Tea Catechins Have Antibacterial Properties That Help Combat Methicillin-resistant Staphylococcus aureus (MRSA)

    Staphylococcusaureus (S. aureus) is a bacteria that can be found on the skin or nose. It can cause a variety of ailments and disorders, such as skin infections, including boils (from contact with an infected person or objects), and even food poisoning (from consuming contaminated food).

    The link between Japanese green tea and its bacterial properties have been the subject of studies for decades. One study showed that catechins can helpstop the growth of S. aureus [14] and other diarrhea-causing bacteria like E. coli.

    Meanwhile, newer studies also looked at the effect of catechins onMethicillin-resistant Staphylococcus aureus (MRSA). MRSA is a strain of staph that’s resistant to several antibiotics. It can cause lung infections like pneumonia and when left untreated, sepsis.

    5. EGCG May Help Prevent the Growth of Foodborne Bacteria

    Several studies have been done to discover the potential antibacterial effects of green tea catechins on foodborne bacteria like *Helicobacter pylori (H. pylori) and **Escherichia coli (E.coli).

    *What is Helicobacter pylori (H. pylori)?H. pylori is a bacteria that can cause peptic ulcers, gastritis, and is also considered a risk factor for some stomach cancers. While the exact cause of H. pylori infection is still unknown, a person can get infected through direct contact with an infected person’s vomit, saliva, or fecal matter or by consuming contaminated food or water

    **What is Escherichia coli (E. coli)? E. coli is a bacteria that can be acquired from contaminated food or water and direct contact with an infected person. It can cause life-threatening kidney failure in at-risk groups, like older adults or younger children.

    While drinking green tea in itself may not be a preventive measure or cure for diseases, research still shows that it provides certain health benefits. The studies presented in this post show that green tea has antiviral and antibacterial properties that can help fight infection and, with more research and testing, can even provide a new way of approaching treatment for certain diseases.

    Want to experience the health benefits of Japanese green tea for yourself? Check out our wide range of green teas in our online shop. Likewise, if you want to learn more about our products, please feel free to contact us.

    Disclaimer: Please note that this post is intended to provide information and shouldn’t be taken as medical advice. Additionally, any information in this post and any linked posts shouldn’t be used to replace professional medical advice or treatment.

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