Where Does EGCG Come From? Sources and Benefits

January 12, 2026 •

4 min read

Green tea leaves are the most abundant source of the powerful antioxidant epigallocatechin gallate, or EGCG, containing up to 50% of its total polyphenol content. This unique plant compound is a type of catechin and has been extensively studied for its potential health benefits, including reducing inflammation, aiding weight loss, and protecting against certain chronic diseases. While most people associate EGCG with green tea, it is also found in a variety of other foods and beverages.

Quick Summary

EGCG, a catechin polyphenol, originates primarily from the leaves of the Camellia sinensis plant, the source of green tea. It is also present in smaller quantities in various other plants, fruits, and nuts. This potent antioxidant is known for its wide-ranging biological effects and is available through diet and concentrated supplements.

Key Points

Rich Source: The Tea Plant: EGCG is most abundant in the leaves of Camellia sinensis, which is the source of all true teas, including green, black, and oolong.
Green Tea has Highest Concentration: Due to minimal processing and lack of fermentation, green tea retains the highest levels of EGCG among all tea types.
Other Food Sources Exist: Besides tea, smaller quantities of EGCG are found in foods like apples, pears, berries, nuts, and cocoa products.
Supplementation uses Advanced Extraction: High-dose EGCG for supplements is produced by extracting and purifying the compound from green tea leaves using methods like subcritical water extraction and chromatography.
Dosage Varies Significantly: The amount of EGCG in supplements is much higher than in brewed tea and can carry different risks, with very high doses linked to potential liver issues.
Bioavailability Factors: A person's absorption of EGCG can be influenced by diet, genetics, and even the combination with other compounds like Vitamin C.
Research Continues: The full scope of EGCG's health effects and its synergistic properties with other plant compounds are still under investigation.

The Primary Source of EGCG: The Tea Plant

EGCG (epigallocatechin gallate) is a compound most famously derived from the tea plant, Camellia sinensis. This single plant species is cultivated to produce different types of tea, but the processing methods are what determine the concentration of EGCG.

Green Tea: This is the richest and most common source of EGCG. The leaves are harvested and then steamed or pan-fired shortly after, preventing fermentation. This minimal processing is crucial for preserving the EGCG content, making green tea a superior source compared to other tea types.
White Tea: Processed from young tea leaves and buds, white tea is less processed than green tea. It also contains EGCG, though typically in amounts slightly less than green tea.
Oolong Tea: Oolong tea undergoes a partial fermentation process, which reduces some of the EGCG content compared to green tea.
Black Tea: This tea is fully fermented, a process that significantly lowers its EGCG concentration by converting catechins into other compounds like theaflavins and thearubigins.

Other Dietary Sources of EGCG

While tea is the most concentrated and well-known source, EGCG and other catechins are found in smaller amounts across a variety of other plant-based foods. Incorporating these items into your diet can help supplement your intake.

Fruits: A range of pome fruits, berries, and stone fruits contain EGCG. This includes apples, pears, peaches, plums, strawberries, raspberries, and cranberries.
Nuts: Certain nuts also provide EGCG. Some examples are hazelnuts, pecans, and pistachios.
Cocoa Products: The compound can be found in cocoa and its derivative products, such as dark chocolate.
Prune Juice: This beverage is another source of catechins, including EGCG.

The Extraction of EGCG for Supplements

For consumers seeking higher doses than what can be obtained from tea alone, EGCG is available in supplement form, typically as a green tea extract. The manufacturing process involves several steps to isolate and concentrate EGCG from raw tea leaves.

Initial Extraction: The process begins by creating a crude green tea extract, often using subcritical water extraction (SWE) or other solvents like ethanol. SWE is noted for being a "green" and efficient method.
Fractionation: The crude extract is then subjected to chromatography on a special macroporous polar resin.
Elution and Collection: A polar solvent is passed through the resin, which separates the different compounds. EGCG is eluted and collected in a specific fraction.
Concentration and Stabilization: The liquid containing the purified EGCG is concentrated. Stabilizers, like ascorbic acid (Vitamin C) or citric acid, may be added to prevent degradation.
Drying: The concentrated EGCG solution is then dried, often using methods like low-temperature spray drying, to produce a stable powder or microparticles. This retains the antioxidant activity and prepares the EGCG for encapsulation into supplements.

Comparison of EGCG from Green Tea vs. Supplements

There are key differences between consuming EGCG through brewed tea versus taking it as a dietary supplement.


Feature	EGCG from Green Tea	EGCG from Supplements
Concentration	Lower. A single cup provides a moderate dose that varies with brewing time and temperature.	Higher and standardized. Designed for concentrated intake to achieve specific therapeutic levels.
Absorption	Can be affected by what is consumed with the tea. Pairing with meals may reduce bioavailability.	Formulated for enhanced absorption, sometimes including additives like Vitamin C to improve uptake.
Side Effects	Rare. Typical consumption is safe and well-tolerated.	Possible at high doses. Some reports link very high intake of concentrated EGCG to liver issues.
Other Compounds	Contains other beneficial polyphenols and some caffeine.	May be isolated EGCG or a green tea extract containing other catechins and caffeine.
Convenience	Requires regular brewing and consumption.	Offers a convenient way to get a specific, high dose.
Safety	Generally very safe for consumption at regular levels.	Requires caution due to potential toxicity at high concentrations; adherence to dosage is critical.

Beyond Green Tea: The Broader Context

While green tea is undeniably the champion of EGCG sources, the presence of this polyphenol in a variety of other foods underscores its prevalence in the plant kingdom. This broader context is important for understanding how a diverse diet contributes to overall health. For instance, the synergistic effects of EGCG when combined with other compounds found in tea and food are still under investigation and may play a role in its efficacy. Furthermore, factors like genetic variations can influence how EGCG is metabolized in the body, impacting its overall bioavailability and effectiveness for individuals.

The industrial extraction of EGCG enables specific, high-dose supplementation, which is distinct from the regular dietary intake from brewed tea. This distinction is critical for understanding the potential therapeutic effects and safety implications. As research continues to uncover the complex mechanisms through which EGCG influences human health, the distinction between food-based consumption and concentrated supplementation remains an important consideration for both consumers and health professionals.

Conclusion

EGCG comes primarily from the leaves of the Camellia sinensis plant, the source of green tea, and is most concentrated in less-processed varieties like green and white tea due to minimized fermentation. This powerful antioxidant can also be found in smaller amounts in various fruits, nuts, and cocoa products. For those seeking higher concentrations, EGCG is extracted from tea leaves using advanced techniques like chromatography and subcritical water extraction to create dietary supplements. While consuming EGCG through a daily cup of tea is generally considered safe and beneficial, supplements offer a much more concentrated dose that requires careful attention to avoid potential adverse effects, particularly concerning liver health at very high levels. Understanding these varied sources and concentrations is essential for making informed choices about incorporating this potent polyphenol into a healthy lifestyle.

Frequently Asked Questions

EGCG, or epigallocatechin gallate, is a type of catechin, which is a class of flavonoid polyphenols found in plants. It is a powerful antioxidant, meaning it helps protect the body's cells from damage caused by free radicals.

Green tea contains the highest concentration of EGCG because the leaves are minimally processed and not fermented, a process that breaks down catechins.

Yes, true teas (green, black, white, and oolong) all come from the same plant, Camellia sinensis. The difference in tea type and EGCG content is determined by the specific harvesting and processing methods used.

Yes, although in smaller amounts. EGCG is present in various fruits, including apples, pears, and berries, as well as nuts like hazelnuts and certain cocoa products.

EGCG supplements are generally considered safe when taken within recommended dosage limits. However, very high doses, particularly when consuming concentrated extracts, have been linked to potential liver toxicity in some studies.

EGCG is extracted from green tea leaves using techniques such as chromatography and subcritical water extraction. This process isolates and concentrates the EGCG, which is then dried into a powder for use in supplements.

The choice depends on your health goals. Drinking green tea provides a natural, moderate dose of EGCG along with other beneficial compounds and is very safe. Supplements offer a concentrated, higher dose but come with a higher risk of side effects if not taken as directed.