Green Tea or EGCG - CancerChoices

Green tea and its extracts may provide substantial benefit for body terrain factors, especially body weight, high blood sugar and insulin resistance, inflammation, oxidative stress, each of which is linked to cancer development and growth.

Green tea or EGCG at a glance

Compared to other teas, green tea contains the highest amount of bioactive compounds that belong to the polyphenol group.1Mokbel K, Mokbel K. Chemoprevention of breast cancer with vitamins and micronutrients: a concise review. In Vivo. 2019 Jul-Aug;33(4):983-997; Dufresne CJ, Farnworth ER. A review of latest research findings on the health promotion properties of tea. Journal of Nutritional Biochemistry. 2001 Jul;12(7):404-421. The primary active constituent in green tea is epigallocatechin-3-gallate (EGCG), but other compounds are also active. Green tea is widely available as a beverage, and extracts, supplements, and topical formulations are also available from drug stores or pharmacies.

The best evidence of benefit from drinking green tea or taking green tea extracts relates to improving body terrain factors, especially body weight, high blood sugar and insulin resistancea condition in which cells in your muscles, fat, and liver don’t respond well to insulin and can’t efficiently take up glucose from your blood for energy, inflammation, and oxidative stressan imbalance between free radicals and antioxidants in your body in which antioxidant levels are lower than normal; this imbalance can cause harmful oxidation reactions in your body chemistry. Each of these factors has known connections to cancer development and growth. Related to this, green tea and its extracts are also linked to lower risk of many types of cancer. Green tea or extracts may also help manage side effects and symptoms including fatigue and gastrointestinal symptoms.

Some safety concerns are noted. Supervision by a medical professional is highly recommended when using green tea, especially during cancer treatment. 

CancerChoices ratings for green tea or EGCG

We rate green tea or EGCG on seven attributes, with 0 the lowest rating and 5 the highest. We rate the strength of the evidence supporting the use of green tea or EGCG for a medical benefit, such as improving treatment outcomes or managing side effects.

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Improving treatment outcomes

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Optimizing your body terrain

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Managing side effects and promoting wellness

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Reducing cancer risk

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Use by integrative oncology experts

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Affordability and access

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Keep reading about green tea or EGCG


Nancy Hepp, MS

Lead Researcher
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Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher and writer for CancerChoices and also served as the first program manager. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.

Nancy Hepp, MS Lead Researcher


Andrew Jackson, ND

Research Associate
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Andrew Jackson, ND, serves as a CancerChoices research associate. As a naturopathic physician practicing in Kirkland, Washington, he teaches critical evaluation of the medical literture at Bastyr University in Kenmore, Washington. His great appreciation of scientific inquiry and the scientific process has led him to view research with a critical eye.

Andrew Jackson, ND Research Associate

Last update: May 9, 2024

Last full literature review: January 2024

CancerChoices provides information about integrative in cancer care, a patient-centered approach combining the best of conventional care, self care and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies and self-care lifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.

Our staff have no financial conflicts of interest to declare. We receive no funds from any manufacturers or retailers gaining financial profit by promoting or discouraging therapies mentioned on this site.

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