Understanding Antioxidants: Does Green Tea Contain CGA?

October 23, 2025 •

4 min read

While coffee is famously rich in chlorogenic acid (CGA), green tea's claim to fame lies with a different family of potent antioxidants known as catechins. So, does green tea contain CGA? The answer is yes, but in significantly smaller amounts compared to its dominant polyphenols.

Quick Summary

Green tea does contain chlorogenic acid (CGA), though it's most renowned for its high catechin content, particularly EGCG. This article contrasts their antioxidant profiles and explains why green tea isn't a primary CGA source.

Key Points

CGA is Present, but Not Dominant: Green tea does contain chlorogenic acid (CGA), but it is a minor component compared to its main antioxidants.
EGCG is Green Tea's Star Antioxidant: The majority of green tea's health benefits are attributed to its high concentration of catechins, especially EGCG.
Coffee is the Primary CGA Source: Chlorogenic acid is most abundant in coffee beans, especially unroasted green coffee beans, where it is the most prominent polyphenol.
Processing Affects Antioxidants: The high-heat roasting of coffee significantly reduces CGA, while green tea's minimal processing preserves its catechins.
Different Antioxidants, Different Benefits: EGCG in green tea and CGA in coffee both offer health advantages, but they operate through different metabolic pathways.
Optimal Brewing Varies: For both beverages, proper brewing time and temperature are critical for maximizing the extraction and retention of their respective antioxidant compounds.

The Core Antioxidants in Green Tea

Green tea, derived from the Camellia sinensis plant, is celebrated worldwide for its potent antioxidant properties. The vast majority of its health benefits are attributed to its high concentration of polyphenols, which constitute 25–35% of the tea leaf's dry weight. The most significant subgroup of these polyphenols are the catechins, with epigallocatechin-3-gallate (EGCG) being the most abundant and studied. EGCG is a powerful antioxidant that helps combat oxidative stress and inflammation, contributing to green tea's health reputation.

The Presence of CGA in Green Tea

While catechins like EGCG are the primary focus of green tea research, the leaves also contain other phenolic compounds, including phenolic acids. Chlorogenic acid (CGA) belongs to this group of phenolic acids and is indeed found in green tea, albeit in much lower quantities than its famous cousin in coffee. Some studies have quantified the CGA content in certain tea cultivars, finding significant variations depending on the variety and processing. Therefore, while present, CGA is not the main driver of green tea's antioxidant activity or its purported health benefits.

Green Tea vs. Coffee: A Tale of Two Antioxidants

To understand the role of CGA in green tea, it's helpful to compare it to coffee, where CGA is the most abundant polyphenol. This comparison highlights the distinct antioxidant profiles of these two popular beverages.


Feature	Green Tea	Coffee
Primary Antioxidant	Catechins (especially EGCG)	Chlorogenic Acid (CGA)
Antioxidant Content	Contains about 90% polyphenols, mainly catechins.	High in antioxidants, particularly CGA.
Caffeine Content	Lower caffeine (approx. 29 mg per 8-oz cup).	Higher caffeine (approx. 96 mg per 8-oz cup).
Antioxidant Breakdown	EGCG and other catechins are relatively stable in hot water for typical brewing durations.	CGA is thermally unstable and degrades significantly during the roasting process.
Processing Impact	Green tea is minimally processed, preserving catechins.	Roasting significantly reduces CGA content; green (unroasted) coffee beans are much higher in CGA.
Metabolic Effects	EGCG is linked to improved metabolic function and fat oxidation.	CGA is associated with improved glucose tolerance and lower fat storage.

Factors Influencing Polyphenol Content

Several factors can influence the final concentration of polyphenols like CGA and EGCG in your brew. For green tea, the amount of catechins can be affected by the variety of the tea plant, its origin, and the growing conditions. For both green tea and coffee, the processing and preparation techniques play a crucial role:

Processing: The key difference lies in the level of processing. Green tea leaves are steamed or pan-fired shortly after harvesting to prevent oxidation, thus preserving high levels of catechins. Coffee beans, on the other hand, undergo a high-heat roasting process that can destroy much of the naturally occurring CGA, which is why green (unroasted) coffee bean extract is a popular source of concentrated CGA.
Brewing Temperature and Time: How you brew your tea matters. Higher temperatures and longer steeping times can increase the extraction of catechins from green tea leaves, but can also cause some degradation if conditions are too harsh. In the case of coffee, brewing methods and time also impact the extraction of remaining CGA, though the initial roasting is the most significant factor.

The Respective Health Benefits of EGCG and CGA

Despite being found in different concentrations in green tea and coffee, both EGCG and CGA are powerful polyphenols with overlapping and distinct health benefits.

Benefits primarily associated with EGCG in green tea:

Cognitive Function: Studies suggest that the compounds in green tea, including EGCG and L-theanine, may improve cognitive function, mood, and brain health.
Cardiovascular Health: Research points to the anti-inflammatory properties of green tea catechins, which help protect heart health by targeting free radicals.
Anticancer Effects: EGCG has shown potential in hindering tumor growth and spreading in animal and cell studies, though more human research is needed.
Weight Management: EGCG, combined with caffeine, may synergistically promote fat oxidation and weight loss.
Skin Protection: Topical application and consumption of green tea extracts have demonstrated anti-inflammatory effects that may protect the skin.

Benefits primarily associated with CGA in green coffee:

Metabolic Health: CGA helps regulate glucose levels, improves insulin sensitivity, and can reduce fat storage, which benefits metabolic syndrome and type 2 diabetes.
Weight Management: Green coffee bean extract rich in CGA has been shown in some human studies to aid in weight loss and reduce fat accumulation.
Cardiovascular Health: CGA may lower blood pressure and protect against heart disease.
Liver Health: Research suggests that CGA has hepatoprotective effects and can aid in managing metabolic dysfunction-associated steatotic liver disease (MASLD).

Conclusion

In conclusion, while green tea is not a primary source of chlorogenic acid (CGA), it does contain trace amounts of this phenolic compound. The bulk of green tea's antioxidant power, however, comes from its exceptionally high concentration of catechins, with EGCG leading the charge. CGA, in contrast, is the dominant antioxidant found in coffee, particularly in unroasted green coffee beans. Both EGCG and CGA offer a wide array of research-backed health benefits, but they act through different mechanisms and are best obtained from their respective primary sources. For those seeking the specific benefits of CGA, green coffee bean extract is a far more concentrated source than green tea. Appreciating the distinct profiles of these powerful beverages allows for more informed dietary choices.

The Difference in Antioxidant Strength

It is important to remember that the health impact of green tea is not diminished by its lower CGA content. Its potent catechin profile provides a unique set of benefits, making it an excellent addition to a healthy diet. The same can be said for coffee, whose strong CGA content and other compounds offer their own advantages. The key takeaway is to recognize that different plants offer different phytochemicals, and a varied diet rich in both can maximize your intake of beneficial antioxidants.

To learn more about the science behind polyphenols, explore this article on the National Library of Medicine website.(https://pmc.ncbi.nlm.nih.gov/articles/PMC11205996/)

Frequently Asked Questions

Yes, black tea, like green tea, is derived from the Camellia sinensis plant and contains some chlorogenic acid (CGA). However, the fermentation process used to produce black tea alters its polyphenol profile, and like green tea, its primary antioxidants are not CGA.

Both are excellent sources of antioxidants, but they contain different types. Green tea is superior for catechins like EGCG, while unroasted green coffee is a far richer source of chlorogenic acid (CGA).

While green tea contributes a small amount of CGA, it is not considered a significant source. If your goal is to increase CGA intake, sources like green coffee bean extract or certain fruits and vegetables would be more effective.

The CGA content of green tea is affected by extraction methods. Some studies have shown that different processing techniques and brewing conditions can influence the final levels of phenolic compounds.

CGA and EGCG are both powerful antioxidant polyphenols, but they belong to different chemical classes. CGA is a phenolic acid and is the main antioxidant in coffee, while EGCG is a catechin and is the primary antioxidant in green tea.

Yes, some studies suggest that combining green tea catechins and coffee's CGA can have synergistic effects on metabolism and glucose control. One study found that combining green tea and coffee extracts improved metabolic parameters in rats.

Chlorogenic acid is thermally unstable, and much of it is broken down into caffeic and quinic acids during the high-heat roasting process of coffee beans. This is why green (unroasted) coffee beans are a much higher source of CGA.