Gaia Herbs | plant intelligence

Green Tea


Through archaeological carbon dating, it was discovered that Green Tea leaves were first boiled in water over 500,000 years ago. It has been cultivated in India, China, and Japan for hundreds of centuries and has been used for at least five thousand years to support digestion, promote a healthy cardiovascular system, promote healthy metabolism of sugars, provide support for clear thinking and encourage an energetic lifestyle. Its consumption worldwide is second only to water. Green tea comes from the unfermented leaves of the Camellia sinensis shrub, while oolong tea is partially fermented, and black tea is fully fermented and has the highest caffeine and lowest antioxidant activity. Green tea has been shown to have the some of the highest antioxidant activity of any plant known. It was shown to have more antioxidant capacity than both Vitamin C and Vitamin E in a study conducted in 1989.


The thermogenic properties of Green Tea and its role in encouraging the healthy metabolism of sugars make it an excellent choice for the support of a weight management protocol. The antioxidant activity of Green Tea is well documented and attributed to the polyphenols known collectively as catechins; epigallocatechin (EGC), epicatechin (EC), epigallocatechingallate (EGCG) and epicatecatechingallate (ECG). The chemical structure of these antioxidants not only impedes the action of free radicals as oxidative stressors but prevents their formation. Many integrative health protocols for the support of the immune system involve using natural health supplements high in antioxidants, including Green Tea which has substantial in vitro clinical validation of its supportive role in reducing the effects of oxidative stress.

Uses of Green Tea


This information in our Herbal Reference Guide is intended only as a general reference for further exploration, and is not a replacement for professional health advice. This content does not provide dosage information, format recommendations, toxicity levels, or possible interactions with prescription drugs. Accordingly, this information should be used only under the direct supervision of a qualified health practitioner such as a naturopathic physician.

Active Constituents

Green Tea contains hundreds of pharmacologically active chemicals. The most researched of these are the alkaloids (thoebromine, theophylline, and caffeine), tannins, and polyphenols known collectively as catechins; epigallocatechin (EGC), epicatechin (EC), epigallocatechingallate (EGCG) and epicatecatechingallate (ECG).

Parts Used

  • Leaves

Important precautions

Additional Resources

Zhao BL, et al. Cell Biophys. 1989 Apr; 14(2): 175-85 Scavenging effects of extracts of green tea and natural antioxidants on active oxygen radicals.

Coimbra, S et al. Clin. Nutr. 2006 May 12.

Yance DR Jr, Sagar SM. 2006 Mar; 5(1) 9-29.

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