EGCG Benefits: Side Effects, Dosage & How to Use
EGCG has long been recognized as a standout compound in green tea extract, offering multiple health-supporting effects. However, ongoing debates question whether prolonged use of EGCG might pose risks to liver or kidney function.
In this article, we’ll explore its key benefits, proper usage, recommended dosage, and important safety considerations surrounding this green tea-derived compound.
Before exploring further, please read the disclaimer located at the end of this webpage.
Key Takeaways
- EGCG is a powerful antioxidant and a major polyphenol in green tea.
- Common dietary sources include green and black tea. A standard 250ml cup of green tea typically contains approximately 50–100 mg of EGCG.
- EGCG itself is not caffeine, but consuming green tea provides both EGCG and caffeine naturally present in the leaves.
- Suggested dosage: 150–400 mg/day for healthy adults. Experts generally advise against exceeding ~800 mg/day.
What Is EGCG and What Does EGCG Do for the Body?
EGCG (Epigallocatechin Gallate) is a key polyphenolic compound primarily found in green tea leaves (Camellia sinensis), accounting for approximately 40–50% of the total polyphenol content.
It is considered one of the most biologically active compounds in tea, contributing significantly to its overall health benefits (Capasso, et al. 2025).
Compared to other catechins like EC (Epicatechin), EGC (Epigallocatechin), and ECG (Epicatechin Gallate), EGCG stands out as the most potent. The main differentiator lies in its gallate group attachment, which enhances its bioactivity and cellular protective properties (Guo, et al. 2005).
While this research demonstrates cellular-level effects of green tea polyphenols, its findings have not been clinically validated in human populations.
Functionally, EGCG acts as a robust antioxidant, helping neutralize free radicals and minimize cellular damage.
It also exhibits anti-inflammatory properties by blocking pathways that trigger inflammatory responses. Numerous studies show that EGCG supports lipid and glucose metabolism, contributes to lower cholesterol and blood fat levels, and promotes heart health while helping manage body weight (Capasso, et al. 2025).
Additionally, EGCG may benefit immune function and gut microbiota, supporting the body’s immune resilience and digestive health.
Due to its multifaceted benefits, EGCG is regarded as an essential bioactive for anyone focused on comprehensive wellness and proactive health maintenance (Capasso, et al. 2025).
Let’s now take a closer look at the most prominent health benefits associated with EGCG.
Key Health Benefits of EGCG
Antioxidants and Anti-Inflammation
EGCG is a powerful antioxidant known to neutralize free radicals and limit oxidative reactions in the body.
One study investigating EGCG found that it inhibits the accumulation of reactive oxygen species (ROS) and modulates cellular signaling pathways to reduce inflammatory responses. It lowers nitric oxide levels and oxidative stress overall (Guo, et al. 2005).
Further evidence shows EGCG actively suppresses ROS production, reduces nitric oxide concentrations, and interferes with inflammatory mediators. This results in cellular-level inflammation control and protects tissues and blood vessels from oxidative damage.
The anti-inflammatory effects of EGCG are also believed to reduce risks of chronic inflammatory conditions such as cardiovascular disease, type 2 diabetes (Singh R, et al. 2010).
This finding was observed in human-derived SH-SY5Y cells in a laboratory model of neurodegeneration and has not yet been confirmed in clinical trials.
Thanks to these actions, EGCG plays a meaningful role in reinforcing the body’s natural defenses against inflammation, oxidative aging, and related health concerns.
Supports Cardiovascular Health
EGCG supports cardiovascular wellness through multiple pathways. Flavonoids found in tea, including EGCG, help dilate blood vessels, improve endothelial function, and lower blood pressure.
They also contribute to reducing LDL (low-density lipoprotein) cholesterol levels—the “bad” cholesterol (Legeay, et al. 2015).
More specifically, studies have shown that people who drink green tea daily have a lower risk of cardiovascular disease than those who do not.
One laboratory study also found that catechin-rich green tea extract significantly reduced both systolic and diastolic blood pressure in overweight, hypertensive people (Syeda, et al. 2025).
In summary, due to its anti-inflammatory and antioxidant mechanisms, EGCG may support vascular function and circulatory health through its antioxidant and anti-inflammatory mechanisms, EGCG may support vascular and circulatory function.
Protects the Brain
Another noteworthy benefit of EGCG is its neuroprotective potential. This benefit primarily stems from EGCG’s strong antioxidant capacity and its influence on cellular signaling pathways in the brain.
Preliminary studies suggest that individuals who drink 2–3 cups of green tea daily over many years have a 30–40% lower risk of developing neurodegenerative diseases like Alzheimer’s and Parkinson’s compared to non-tea drinkers (Singh R, et al., 2010).
This effect is attributed to EGCG’s ability to reduce oxidative stress in neurons, enhance cerebral blood flow, and stimulate the regeneration of new brain cells.
These benefits may help preserve memory and cognitive functions as we age and potentially improve learning capacity. However, more comprehensive and large-scale human studies are needed to fully confirm these mechanisms and long-term effects of EGCG on brain health.
Supports Metabolism and Weight Loss
First, it’s important to understand that EGCG does not directly “burn fat” or cause immediate weight loss.
Rather, it works by promoting thermogenesis (the body’s calorie-burning process) and inhibiting lipid accumulation in the liver through anti-inflammatory actions and suppression of fat-metabolizing enzymes (Qian Yi, et al., 2018).
In the book Antioxidants in Sport Nutrition, the authors reference clinical trials indicating that prolonged EGCG supplementation, especially in combination with caffeine, may contribute to reductions in body weight and total body fat compared to placebo.
Another study also found that combining EGCG with caffeine had a greater impact on fat reduction.
Adults with excess body fat who took a combination of EGCG and caffeine over several months experienced a measurable decrease in fat mass compared to the control group (Vázquez Cisneros, et al., 2017).
That said, EGCG's weight loss effects are most noticeable when combined with a balanced diet and regular exercise. So don’t forget—adopting a healthy lifestyle remains key!
Supports Cellular health
EGCG has been the subject of scientific research exploring its potential role in supporting cellular health and maintaining normal cell growth.
Laboratory studies have observed that EGCG may influence processes such as cell signaling, oxidative stress, and angiogenesis, which are involved in abnormal cell proliferation.
In vitro experiments have demonstrated its ability to affect cancer cell lines, including those derived from breast, lung, and prostate tissues (Capasso et al., 2025).
These findings suggest possible mechanisms by which EGCG might help support DNA integrity and healthy cell function.
However, most of this research has been conducted in cell cultures or animal models. Clinical studies in humans are still limited, and more research is needed before any conclusions can be made about EGCG’s effects on human health.
How to Take EGCG: Natural Sources and Supplements
EGCG can be consumed via dietary intake or through concentrated supplements. The simplest way is by drinking green tea or black tea daily.
A standard 250ml cup of green tea typically contains around 50–100 mg of EGCG (Antioxidants in Sport Nutrition). It also contains caffeine and other beneficial phytonutrients.
Drinking green tea offers hydration along with EGCG intake. However, if you're not a fan of its taste or find it difficult to consume regularly, you can opt for green tea-based products like matcha, Japanese green tea powders, or even EGCG-specific supplements.
|
Criteria |
Natural Green Tea |
EGCG Supplements (Concentrated) |
|
Additional Components |
Caffeine (~30–40 mg/cup), theanine, other polyphenols |
Primarily EGCG; may or may not contain caffeine |
|
Advantages |
Natural source, provides hydration, nutrients; dosage can be adjusted via tea volume |
Precise dosage, easy to meet high-intake targets; convenient for consistent supplementation |
|
Disadvantages |
Requires multiple cups to meet high intake; contains caffeine (can disrupt sleep or overstimulate); contains oxalates (risk of kidney stones if overconsumed) |
Higher cost; may contain additives or impurities when purchasing poor quality goods |
In addition, pairing EGCG with caffeine may enhance its absorption and synergistic effects. Regardless of your preference, it’s important to evaluate your needs and choose the method that suits your lifestyle and health goals best.
How Much EGCG Per Day Should You Take? EGCG Safety
For healthy adults, the recommended daily intake of EGCG generally starts at 150 mg/day. Research shows that consuming between 150–2,500 mg of catechins per day from green tea or its extracts may lead to improved cholesterol levels and other health benefits (Zheng, et al., 2011).
While some studies have demonstrated benefits at higher doses, experts advise not exceeding 400–800 mg/day, especially when taken in supplement form, due to the increased risk of liver toxicity (EFSA).
In human clinical trials, high doses in the hundreds of milligrams did not always show clear toxicity, but liver-related side effects were more commonly reported at doses above 800 mg/day (EFSA).
Certain individuals should exercise additional caution: pregnant or breastfeeding women, people with liver or kidney disease, cardiovascular conditions, or diabetes should avoid high doses or consult healthcare providers before using EGCG, particularly in concentrated forms.
EGCG vs Other Green Tea Catechins: What’s the Difference?
Green tea contains several catechins, with EGCG being the most abundant and potent. Data shows that EGCG accounts for 40–69% of total catechins in green tea, while other key catechins include ECG (13–21%), EGC (12–23%), and EC (5–9%) (Syeda, et al., 2025).
The key differentiator: EGCG contains a gallic acid group, which significantly enhances its antioxidant activity.
|
Catechin |
Proportion in Green Tea (%) |
Contains Gallic Acid |
Antioxidant Power |
|
EGCG |
40–69 |
Yes |
Very strong (strongest) |
|
ECG |
13–21 |
Yes |
Strong |
|
EGC |
12–23 |
No |
Moderate |
|
EC |
5–9 |
No |
Weakest |
Thus, EGCG not only dominates in quantity but also outperforms other catechins in biological activity, making it the primary compound of interest in most green tea-related studies.
Should You Take EGCG Supplements?
For most people, daily green tea consumption (2–4 cups of quality tea) is sufficient to meet EGCG needs while also delivering additional nutrients like theanine, vitamins, and minerals. This is a safe and practical approach.
However, if you dislike the strong taste of tea or are targeting specific health goals, EGCG supplements can be a more controlled and efficient option.
When using supplements, choose reputable brands that clearly label EGCG content and origin. Start with a low dose (100–200 mg/day) and monitor how your body responds.
Keep in mind that higher doses come with higher risks, particularly for liver health. Always consult a healthcare provider before combining EGCG with prescription medications or using long-term.
Frequently Asked Questions
1. Does EGCG Have Caffeine?
No, EGCG itself is not caffeine and does not naturally contain caffeine. However, since it’s often consumed via green or black tea, which contains caffeine, the two compounds are commonly ingested together. If you want caffeine-free EGCG, opt for purified supplements that are explicitly labeled as decaffeinated.
2. Does EGCG Burn Belly Fat?
EGCG does not directly target belly fat. Instead, it aids overall fat metabolism by increasing thermogenesis and inhibiting lipid accumulation (Qian Yi, et al., 2018). For optimal fat loss, EGCG should be paired with a healthy diet and regular exercise. It acts as a supporting compound, not a standalone fat burner.
3. Is It Safe To Take EGCG Daily?
Yes, EGCG is generally safe for daily use when taken at moderate, controlled doses. Drinking 2–4 cups of green tea daily (providing 150–400 mg EGCG) is well-tolerated for most healthy adults (Zheng, et al., 2011). For high-concentration supplements, avoid exceeding 800 mg/day, which may increase the risk of liver toxicity (EFSA). If you experience unusual symptoms such as nausea or fatigue, discontinue use and consult a healthcare provider.
4. What Are The Side Effects Of Taking EGCG?
Common side effects, especially at high doses or in sensitive individuals include nausea, stomach upset, indigestion, and occasionally headaches (Capasso, et al., 2025). Prolonged use at excessive doses can lead to liver damage or worsen existing health conditions. Seek medical advice if you suspect adverse effects from EGCG.
5. Does EGCG Increase Estrogen?
No, EGCG does not increase estrogen levels. In fact, some studies suggest it may inhibit estrogen-mimicking compounds (Baker, et al., 2015). EGCG is not a phytoestrogen and does not significantly impact natural estrogen production in the body. This is important for those concerned about hormonal balance.
6. Is EGCG Hard On The Liver?
Using EGCG at doses exceeding 800 mg/day may place a significant burden on the liver. Excessive intake can delay absorption and elimination, leading to increased liver enzymes and potential liver cell damage. Therefore, controlling dosage is essential when incorporating EGCG into your routine.
7. Can EGCG Raise Blood Pressure?
No. In fact, EGCG tends to support blood pressure regulation. Clinical trials have shown that supplementing with green tea extracts rich in EGCG resulted in significant reductions in both systolic and diastolic blood pressure among individuals with hypertension compared to placebo (Syeda, et al. 2025). Thus, EGCG, especially when combined with caffeine, does not raise blood pressure.
8. Is It Better To Drink Green Tea Or Take Green Tea Extract?
Both are safe options, but they serve different purposes. Drinking pure green tea is ideal for those seeking a natural, gradual, and long-term approach with added hydration and polyphenols. On the other hand, green tea extract provides a more concentrated and convenient dose, which may be suitable for those with targeted health goals, but it also carries greater risk if misused, especially at high doses.
9. Does EGCG Block Iron Absorption?
Yes. EGCG, along with other green tea polyphenols, can interfere with the absorption of non-heme iron (from plant sources) in the intestines. Consuming EGCG or green tea alongside iron-rich meals can reduce the amount of iron absorbed (Capasso, et al. 2025). If you’re addressing iron deficiency or using iron supplements, it’s best to separate EGCG or tea intake by 1–2 hours from iron-rich foods.
10. Does EGCG Lower Testosterone?
Currently, there is no clear or direct evidence in humans showing that EGCG lowers testosterone levels. One rodent study using extremely high injected doses of EGCG reported a reduction in testosterone by approximately 75%. However, this does not reflect normal dietary intake levels from tea or supplements in humans.
11. Does Green Tea Interact With Estrogen?
EGCG in green tea may interact with estrogen receptors (ER), but its effect is primarily in modulating or inhibiting the activity of certain exogenous estrogens. Drinking green tea regularly does not significantly alter endogenous estrogen levels in humans.
12. Is EGCG Stimulating?
No. EGCG is not a stimulant like caffeine. It does not cause nervous system excitation or heightened alertness. Any “wakefulness” effect you feel from green tea is due to its caffeine content, not EGCG.
13. What Does EGCG Do To Skin?
EGCG may benefit the skin through its antioxidant and anti-inflammatory actions. Research suggests EGCG supports wound healing and reduces inflammation and scar formation (Mazlan, et al. 2021). Additionally, it can help protect skin from UV-induced oxidative stress by neutralizing free radicals.
14. Is EGCG Hard On The Kidneys?
For healthy individuals, EGCG at normal dietary levels is not considered harmful to the kidneys. However, people with pre-existing kidney issues should be cautious with high doses and avoid concentrated EGCG extracts.
15. What Is The Best Time Of Day To Take EGCG?
Research suggests that EGCG is best absorbed on an empty stomach, such as in the morning before eating. However, if EGCG causes gastric discomfort, you can take it with a small snack. Since green tea contains caffeine, avoid tea intake after 2 PM if you’re sensitive.
Conclusion
In summary, EGCG is a versatile compound with potential benefits across multiple health areas and is generally easy to incorporate into daily life.
For most people, adding green tea to the diet or using a well-dosed extract can be a safe and practical option. However, be mindful of daily intake limits to avoid unwanted effects. When used appropriately, EGCG may positively support your overall wellness.
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*The testimonials presented on this website are provided by individuals based on their personal experiences with our products. These testimonials represent individual opinions and experiences, which may not be typical or applicable to all users of our products. Results may vary depending on a variety of factors, including individual health, lifestyle, and adherence to product usage instructions.References
- [1] Capasso, Lucia, et al. “Epigallocatechin Gallate (EGCG): Pharmacological Properties, Biological Activities and Therapeutic Potential.” Molecules, vol. 30, no. 3, Multidisciplinary Digital Publishing Institute, Feb. 2025, pp. 654–54, https://doi.org/10.3390/molecules30030654.
- [2] Guo, Shuhong, et al. “Protective Effect of Green Tea Polyphenols on the SH-SY5Y Cells against 6-OHDA Induced Apoptosis through ROS–NO Pathway.” Free Radical Biology and Medicine, vol. 39, no. 5, Elsevier BV, May 2005, pp. 682–95, https://doi.org/10.1016/j.freeradbiomed.2005.04.022.
- [3] Singh R, Akhtar N, Haqqi TM. Green tea polyphenol epigallocatechin-3-gallate: inflammation and arthritis. Life Sci. Elsevier Inc.; 2010;86(25-26):907–18. Available from: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=3146294
- [4] Legeay, Samuel, et al. “Epigallocatechin Gallate: A Review of Its Beneficial Properties to Prevent Metabolic Syndrome.” Nutrients, vol. 7, no. 7, Multidisciplinary Digital Publishing Institute, July 2015, pp. 5443–68, https://doi.org/10.3390/nu7075230.
- [5] Syeda Tajammal, et al. “Green Tea Polyphenols in Wound Healing: Therapeutic Mechanisms, Potential Applications and Challenges in Commercial Use for Diabetic Wound Healing.” Processes, vol. 13, no. 3, Multidisciplinary Digital Publishing Institute, Feb. 2025, pp. 653–53, https://doi.org/10.3390/pr13030653.
- [6] Eng, Qian Yi, et al. “Molecular Understanding of Epigallocatechin Gallate (EGCG) in Cardiovascular and Metabolic Diseases.” Journal of Ethnopharmacology, vol. 210, Elsevier BV, Jan. 2018, pp. 296–310, https://doi.org/10.1016/j.jep.2017.08.035.
- [7] Jówko, Ewa. “Green Tea Catechins and Sport Performance.” Nih.gov, CRC Press/Taylor & Francis, 2015, www.ncbi.nlm.nih.gov/books/NBK299060/.
- [8] Vázquez Cisneros, Lucía Cristina, et al. “Efectos Del Té Verde Y Su Contenido de Galato de Epigalocatequina (EGCG) Sobre El Peso Corporal Y La Masa Grasa En Humanos. Una Revisión Sistemática.” Nutrición Hospitalaria, vol. 34, no. 3, ARAN Ediciones, June 2017, p. 731, https://doi.org/10.20960/nh.753.
- [9] Zheng, Xin-Xin, et al. “Green Tea Intake Lowers Fasting Serum Total and LDL Cholesterol in Adults: A Meta-Analysis of 14 Randomized Controlled Trials.” American Journal of Clinical Nutrition, vol. 94, no. 2, Elsevier BV, June 2011, pp. 601–10, https://doi.org/10.3945/ajcn.110.010926.
- [10] “EFSA Assesses Safety of Green Tea Catechins.” European Food Safety Authority, 18 Apr. 2018, www.efsa.europa.eu/en/press/news/180418.
- [11] “Scientific Opinion on the Safety of Green Tea Catechins.” European Food Safety Authority, 18 Apr. 2018, www.efsa.europa.eu/en/efsajournal/pub/5239.
- [12] Baker, Kimberly Mantzke, and Angela C. Bauer. “Green Tea Catechin, EGCG, Suppresses PCB 102-Induced Proliferation in Estrogen-Sensitive Breast Cancer Cells.” International Journal of Breast Cancer, vol. 2015, Hindawi Publishing Corporation, Jan. 2015, pp. 1–7, https://doi.org/10.1155/2015/163591.
- [13] The Medicinal Action of Androgens and Green Tea Epigallocatechin Gallate. www.hkmj.org/system/files/hkm0112p369.pdf.
- [14] Mazlan Zawani, and Mh Fauzi. “Epigallocatechin Gallate: The Emerging Wound Healing Potential of Multifunctional Biomaterials for Future Precision Medicine Treatment Strategies.” Polymers, vol. 13, no. 21, Multidisciplinary Digital Publishing Institute, Oct. 2021, pp. 3656–56, https://doi.org/10.3390/polym13213656.
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