Life Extension Mega Green Tea Extract (Decaffeinated): Is Life Extension Mega Green Tea Extract safe?

Yes, Life Extension Mega Green Tea Extract is safe when taken as directed with food. It provides 326mg EGCG per capsule, which is within the EFSA's recommended limit of 800mg EGCG daily. It is decaffeinated, making it safer for caffeine-sensitive individuals.

Life Extension Mega Green Tea Extract (Decaffeinated): Is this product decaffeinated?

Yes, Life Extension Mega Green Tea Extract is decaffeinated, with 95%+ of caffeine removed while preserving catechin content. This makes it suitable for caffeine-sensitive individuals, evening dosing, and those who consume caffeine from other sources.

Life Extension Mega Green Tea Extract (Decaffeinated): Can high-dose green tea extract affect the liver?

Very high doses of EGCG on an empty stomach have been linked to rare liver injury cases. Life Extension's 326mg EGCG per capsule is within safe limits when taken with food. Do not take on an empty stomach and do not exceed 2 capsules daily.

Life Extension Mega Green Tea Extract (Decaffeinated): Are there side effects from Mega Green Tea Extract?

The high polyphenol concentration (98%) may cause nausea or GI discomfort in sensitive individuals, especially on an empty stomach. Start with 1 capsule with food and assess tolerance before considering 2 capsules. Most people tolerate it well.

Life Extension Mega Green Tea Extract (Decaffeinated): Is Life Extension a trustworthy brand?

Yes, Life Extension is a research-focused brand with over 40 years in the industry. They fund independent research, publish in peer-reviewed journals, and third-party test all products. Their formulations are known for being science-driven and high-potency.

Life Extension Mega Green Tea Extract (Decaffeinated): What is the recommended dose?

The recommended serving is 1 capsule daily with food. Each capsule provides 725mg of extract with 326mg EGCG. One capsule delivers a near-clinical dose. Do not exceed 2 capsules daily (652mg EGCG) to stay within EFSA guidelines.

Life Extension Mega Green Tea Extract (Decaffeinated): Must I take this with food?

Yes, always take with food. The high concentration of polyphenols (98%) makes it especially important to have food in your stomach. Taking on an empty stomach significantly increases the risk of nausea and the very rare risk of liver stress.

Life Extension Mega Green Tea Extract (Decaffeinated): Can I take this in the evening?

Yes, the decaffeinated formula makes it suitable for evening use without disrupting sleep. This is a major advantage over caffeinated green tea extracts. Take with your dinner for convenient evening dosing.

Life Extension Mega Green Tea Extract (Decaffeinated): How many capsules are in a bottle?

Each bottle contains 100 vegetarian capsules, providing a 100-day supply at 1 capsule per day. At $0.22/serving, the large count offers good long-term value.

Life Extension Mega Green Tea Extract (Decaffeinated): How long until I notice benefits?

Antioxidant protection starts immediately. Metabolic benefits typically emerge over 8-12 weeks of consistent use. The high-potency formula may produce noticeable effects sooner than lower-dose products.

Life Extension Mega Green Tea Extract (Decaffeinated): What does 98% polyphenol standardization mean?

It means 98% of the extract weight consists of polyphenols (catechins and other phenolic compounds). This is the highest standardization available and indicates an extremely concentrated extract. The 45% EGCG within this provides 326mg per capsule.

Life Extension Mega Green Tea Extract (Decaffeinated): How is the caffeine removed?

The decaffeination process uses methods that remove 95%+ of caffeine while preserving catechins. This may slightly alter the catechin ratio compared to caffeinated extracts, but the EGCG content remains high at 45% standardization.

Life Extension Mega Green Tea Extract (Decaffeinated): Does this product have more EGCG than other brands?

Yes, at 326mg EGCG per capsule, this is one of the highest single-capsule EGCG doses available. NOW Foods provides 200mg per capsule, while Jarrow provides approximately 125mg. Life Extension's product delivers a near-clinical dose in one capsule.

Life Extension Mega Green Tea Extract (Decaffeinated): Is this product Non-GMO?

Yes, Life Extension Mega Green Tea Extract is Non-GMO. Life Extension maintains high sourcing standards and third-party tests all products for identity, potency, and purity.

Life Extension Mega Green Tea Extract (Decaffeinated): What other polyphenols are included beyond EGCG?

The 98% polyphenol extract includes EGCG (primary), epicatechin gallate (ECG), epigallocatechin (EGC), epicatechin (EC), and other phenolic compounds. Together, these provide comprehensive antioxidant protection through multiple mechanisms.

Life Extension Mega Green Tea Extract (Decaffeinated): How effective is this high-dose green tea extract?

The 326mg EGCG per capsule provides one of the most potent single-dose green tea extract options. At this concentration, one capsule delivers approximately 65% of the optimal clinical dose (500mg EGCG). For maximum benefits, it is among the most effective single-capsule options.

Life Extension Mega Green Tea Extract (Decaffeinated): Is decaffeinated extract as effective as caffeinated?

Decaffeination may slightly alter the catechin profile, but the EGCG content remains high (45%). The primary benefits of green tea extract come from EGCG and other catechins, not caffeine. For antioxidant and anti-inflammatory purposes, decaf extracts are equally effective.

Life Extension Mega Green Tea Extract (Decaffeinated): Can this extract support metabolic health?

Yes, EGCG has been studied for metabolic effects including fat oxidation and thermogenesis. At 326mg per capsule, this product provides a potent metabolic dose. Effects are modest and work best alongside a healthy diet and exercise program.

Life Extension Mega Green Tea Extract (Decaffeinated): How does this compare to drinking green tea?

One capsule provides roughly the EGCG equivalent of 3-4 cups of high-quality brewed green tea. The 98% polyphenol standardization ensures much more concentrated and consistent catechin delivery than variable brewing methods.

Life Extension Mega Green Tea Extract (Decaffeinated): How big are the capsules?

The vegetarian capsules are slightly larger than standard due to the 725mg extract fill. They contain a concentrated greenish-brown powder. Most adults find them manageable, though people who struggle with larger pills should be aware.

Life Extension Mega Green Tea Extract (Decaffeinated): How should I store this product?

Store in a cool, dry place away from direct sunlight. The highly concentrated polyphenols can degrade with heat and light exposure. Keep the bottle tightly sealed. No refrigeration is needed.

Life Extension Mega Green Tea Extract (Decaffeinated): Does this product have a taste?

If the capsule is swallowed whole, there is no taste. If accidentally bitten, the highly concentrated extract has a very strong, astringent green tea taste. Swallow whole with a full glass of water.

Life Extension Mega Green Tea Extract (Decaffeinated): Is this product vegan?

Yes, Life Extension Mega Green Tea Extract uses a vegetarian capsule and contains no animal-derived ingredients. It is suitable for vegans and vegetarians.

Life Extension Mega Green Tea Extract (Decaffeinated): Is this product gluten-free?

Yes, this product is gluten-free and free from major allergens. It is suitable for people with celiac disease or gluten sensitivity.

Life Extension Mega Green Tea Extract (Decaffeinated): Can I take this if I avoid caffeine entirely?

While labeled as decaffeinated, trace amounts of caffeine may remain (less than 5% of original content). This is similar to decaf coffee. For most caffeine-sensitive individuals, this trace amount is insignificant, but those with extreme caffeine sensitivity should be aware.

NOW Foods EGCg Green Tea Extract 400mg: Is NOW Foods EGCg Green Tea Extract safe?

Yes, NOW Foods EGCg Green Tea Extract is safe when taken as directed with food. It is GMP-certified and third-party tested. The European Food Safety Authority recommends not exceeding 800mg EGCG daily from supplements. Always take with food to reduce the risk of liver stress.

NOW Foods EGCg Green Tea Extract 400mg: Can green tea extract harm the liver?

High-dose green tea extract on an empty stomach has been associated with rare liver injury cases. NOW's 200mg EGCG per capsule is within safe limits. Always take with food, start with 1 capsule, and stop use if you experience abdominal pain, dark urine, or yellowing of skin.

NOW Foods EGCg Green Tea Extract 400mg: Does NOW EGCg contain caffeine?

Yes, this product contains natural caffeine from green tea (estimated 20-30mg per capsule). Caffeine-sensitive individuals should be aware of this and may prefer a decaffeinated green tea extract. Avoid taking late in the day if caffeine affects your sleep.

NOW Foods EGCg Green Tea Extract 400mg: Can I take NOW EGCg with medications?

Green tea extract may interact with certain medications including blood thinners, stimulants, and some chemotherapy drugs. The caffeine content can also interact with some medications. Consult your pharmacist before combining with prescription drugs.

NOW Foods EGCg Green Tea Extract 400mg: Is NOW Foods a reliable brand for green tea extract?

Yes, NOW Foods has been in the supplement industry for over 50 years with GMP-certified manufacturing. Their EGCg extract is standardized to 50% EGCg and 80% total catechins — among the highest standardization available at this price point.

NOW Foods EGCg Green Tea Extract 400mg: What is the recommended dose of NOW EGCg?

The recommended serving is 1 capsule (200mg EGCg) daily with food. For the clinical trial dose of 400mg EGCg, take 2 capsules. Do not exceed 4 capsules daily (800mg EGCg) per EFSA guidelines.

NOW Foods EGCg Green Tea Extract 400mg: Should I take NOW EGCg with food?

Yes, always take green tea extract with food. Taking concentrated catechins on an empty stomach increases the risk of GI discomfort and has been linked to rare liver injury cases. A meal provides a protective buffer.

NOW Foods EGCg Green Tea Extract 400mg: How many capsules are in a bottle?

Each bottle contains 90 vegetarian capsules. At 1 capsule per day, it lasts 90 days (3 months). At 2 capsules per day, it lasts 45 days. At $0.10/serving, it offers exceptional value.

NOW Foods EGCg Green Tea Extract 400mg: Can I take this with other supplements?

Yes, green tea extract pairs well with most supplements. It may enhance the effects of other antioxidants like vitamin C. However, be mindful of total caffeine intake if you also take caffeine-containing supplements or drink coffee.

NOW Foods EGCg Green Tea Extract 400mg: How long until I see benefits from NOW EGCg?

Antioxidant protection begins immediately. Metabolic and weight management benefits typically require 8-12 weeks of consistent daily use. Anti-inflammatory effects build progressively with daily supplementation.

NOW Foods EGCg Green Tea Extract 400mg: What does 50% EGCg standardization mean?

It means 50% of the extract weight is EGCG (epigallocatechin gallate), the most potent and studied catechin in green tea. In a 400mg extract, this delivers 200mg of pure EGCG. This is one of the highest EGCg standardizations available.

NOW Foods EGCg Green Tea Extract 400mg: What is the total catechin content?

NOW EGCg is standardized to 80% total catechins and 50% EGCg specifically. This means 320mg of total catechins per 400mg capsule, including EGCG, EGC, ECG, and EC. The high catechin content indicates a quality extraction process.

NOW Foods EGCg Green Tea Extract 400mg: Is this product made from whole tea leaves?

This is a concentrated extract of green tea (Camellia sinensis) leaves, standardized for catechin content. It is not a whole food product but rather a pharmaceutical-grade extraction that concentrates the active polyphenols.

NOW Foods EGCg Green Tea Extract 400mg: Does this product contain any artificial ingredients?

No, NOW Foods EGCg uses a clean formula with green tea extract and minimal excipients in a vegetarian capsule. No artificial colors, flavors, or preservatives are added.

NOW Foods EGCg Green Tea Extract 400mg: How much caffeine is in each capsule?

The exact caffeine content is not specified on the label, but is estimated at 20-30mg per capsule based on standard green tea extraction. This is roughly equivalent to a quarter cup of brewed green tea.

NOW Foods EGCg Green Tea Extract 400mg: How effective is NOW EGCg for antioxidant protection?

EGCG is one of the most potent natural antioxidants, with strong free radical scavenging activity. At 200mg per capsule with 80% total catechins, this provides substantial antioxidant protection. Two capsules deliver a clinical-trial-level dose.

NOW Foods EGCg Green Tea Extract 400mg: Can NOW EGCg help with weight management?

Green tea extract has been studied for metabolic effects including modest fat oxidation and thermogenesis. A meta-analysis showed small but significant effects on weight and waist circumference. Effects are modest and work best alongside diet and exercise.

NOW Foods EGCg Green Tea Extract 400mg: How does this compare to drinking green tea?

One capsule provides roughly the EGCG equivalent of 2-3 cups of high-quality brewed green tea, without the liquid volume, tannin taste, or variable catechin content. Standardized extracts provide more consistent and concentrated catechin delivery.

NOW Foods EGCg Green Tea Extract 400mg: Does EGCG have anti-inflammatory properties?

Yes, EGCG has well-documented anti-inflammatory effects through NF-kB modulation and cytokine regulation. It also has antioxidant activity that reduces oxidative stress-driven inflammation. These effects contribute to its cardiovascular and metabolic benefits.

NOW Foods EGCg Green Tea Extract 400mg: How big are the capsules?

The vegetarian capsules are standard size, containing 400mg of green tea extract. They are easy for most adults to swallow. The capsule contains a greenish-brown powder.

NOW Foods EGCg Green Tea Extract 400mg: How should I store NOW EGCg?

Store in a cool, dry place away from direct sunlight and moisture. Green tea catechins can degrade with heat and light exposure. Keep the bottle tightly sealed. No refrigeration is needed.

NOW Foods EGCg Green Tea Extract 400mg: What does the extract look like?

The extract is a greenish-brown fine powder inside a clear vegetarian capsule. The color reflects the natural polyphenol and catechin content. This is normal for high-quality green tea extract.

NOW Foods EGCg Green Tea Extract 400mg: Is NOW EGCg vegan?

Yes, NOW Foods EGCg Green Tea Extract uses a vegan cellulose capsule and contains no animal-derived ingredients. It is also Non-GMO and gluten-free.

Best Green Tea Extract Supplements (2026)

· Updated April 2026

Lab Tested, Evidence Ranked

Supplement Science Editorial Team·Evidence-Based Supplement Research

Published Mar 11, 2026·Reviewed Apr 22, 2026

2,500+Clinical Studies Cited

3Green Tea Extract products evaluated

This content is for informational purposes only and does not constitute medical advice. Statements about dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary — consult your healthcare provider before starting any supplement. Full disclaimer

Our Verdict

The best green tea extract supplement provides 400-500mg EGCG per serving from a standardized extract, ideally decaffeinated, with third-party testing for catechin content and heavy metals.

Best By Category

#1Best Overall / Best High-Dose

Life Extension Mega Green Tea Extract (Decaffeinated)

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#3Best Decaffeinated

Jarrow Formulas Green Tea 500mg

Buy Nowon Amazon

The best green tea extract supplement provides 400-500mg of EGCG (the primary bioactive catechin) per serving from a...

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We evaluated 20+ green tea extract supplements across EGCG content, standardization percentage, caffeine status, third-party testing, and value. Our picks prioritize high-EGCG extracts with verified catechin content and options for caffeine-sensitive individuals.

As an Amazon Associate, we earn from qualifying purchases. Some links below are affiliate links — this doesn't affect our editorial independence or product ratings. How we evaluate products

How We Chose These Products

Products are ranked using our published scoring methodology — evidence strength, dose adequacy, ingredient form, third-party testing signals, value, and clean-label factors are weighted across the 5 criteria below. Commercial relationships do not determine our editorial rankings.

EGCG Content

30%

EGCG (epigallocatechin gallate) is the most potent catechin in green tea and the focus of most clinical research. Products should provide at least 200mg EGCG per serving, with optimal doses at 400-500mg for antioxidant and metabolic benefits.

Standardization

25%

Standardized extracts guarantee consistent catechin content batch to batch. Look for products standardized to at least 45-60% total polyphenols or 50%+ EGCG. Unstandardized products may vary dramatically in potency.

Caffeine Management

20%

Standard green tea extract contains caffeine (typically 30-50mg per capsule). Decaffeinated extracts retain catechins while removing 95%+ of caffeine — important for evening dosing or caffeine-sensitive individuals.

Third-Party Testing

15%

Verification ensures accurate EGCG content and screens for heavy metals, pesticides, and solvent residues from the extraction process.

Value

10%

Cost per milligram of EGCG, adjusted for standardization quality and caffeine status.

#1 Top Pick

Staff Pick

Mega Green Tea Extract (Decaffeinated)

Life Extension

1,657 Amazon reviews

9.2/10

4.4

Delivers a potent 326mg EGCG per capsule from a 98% polyphenol standardized extract — one of the highest concentrations available. Decaffeinated, making it suitable for caffeine-sensitive individuals and evening dosing. Life Extension is a research-driven brand with rigorous quality standards. Single capsule provides a near-clinical dose.

IngredientDecaffeinated Green Tea Extract (standardized to 98% Polyphenols, 45% EGCg)

Dose725mg green tea extract (326mg EGCg) per capsule

FormCapsule

TestingThird-Party Tested

725mg green tea extract (326mg EGCg) per capsuleClinical range: 250-500mg EGCG daily (from 400-800mg GTE)

Clinical dose

$0.23/serving$22.50 · 100 Capsules

Pros

326mg EGCg per capsule (highest per-cap dose)
98% polyphenol standardization
Decaffeinated (caffeine-free)

Cons

Higher price ($0.22/serving)
May cause GI discomfort on empty stomach

Buy Nowon Amazon

Read full review →

Quick Comparison

#1Life Extension Mega Green Tea Extract (Decaffeinated)

9.2/10

Life Extension

#1 Top Pick

1,657 Amazon reviews

Best for: high-dose decaffeinated green tea extract

Decaffeinated Green Tea Extract (standardized to 98% Polyphenols, 45% EGCg) · 725mg green tea extract (326mg EGCg) per capsule

Capsule · Third-Party Tested

$22.50

$0.23/serving

Buy Nowon Amazon

#2NOW Foods EGCg Green Tea Extract 400mg

9/10

NOW Foods

5,555 Amazon reviews

Best for: overall green tea extract

Green Tea Extract (standardized to 80% Total Catechins, 50% EGCg) · 400mg green tea extract (200mg EGCg) per capsule

Capsule · GMP Certified, Third-Party Tested

$11.00

$0.12/serving

Buy Nowon Amazon

#3Jarrow Formulas Green Tea 500mg

8.6/10

Jarrow Formulas

1,882 Amazon reviews

Best for: affordable decaffeinated green tea extract

Green Tea Extract (standardized to 50% Polyphenols) · 500mg green tea extract (250mg polyphenols) per capsule

Capsule · Third-Party Tested

$17.14

$0.17/serving

Buy Nowon Amazon

#	Product	Best For	Ingredient & Dose	Form & Testing	Price	Rating
1	Life Extension Mega Green Tea Extract (Decaffeinated) #1 Top Pick 1,657 Amazon reviews	high-dose decaffeinated green tea extract	Decaffeinated Green Tea Extract (standardized to 98% Polyphenols, 45% EGCg) 725mg green tea extract (326mg EGCg) per capsule	Capsule 100 Capsules Third-Party Tested	$22.50 $0.23/serving	9.2/10	Buy Nowon Amazon
2	NOW Foods EGCg Green Tea Extract 400mg 5,555 Amazon reviews	overall green tea extract	Green Tea Extract (standardized to 80% Total Catechins, 50% EGCg) 400mg green tea extract (200mg EGCg) per capsule	Capsule GMP Certified, Third-Party Tested	$11.00 $0.12/serving	9/10	Buy Nowon Amazon
3	Jarrow Formulas Green Tea 500mg 1,882 Amazon reviews	affordable decaffeinated green tea extract	Green Tea Extract (standardized to 50% Polyphenols) 500mg green tea extract (250mg polyphenols) per capsule	Capsule 100 Capsules Third-Party Tested	$17.14 $0.17/serving	8.6/10	Buy Nowon Amazon

Detailed Reviews

#1 Top Pick

Life Extension Decaffeinated Mega Green Tea Extract – Polyphenol-Rich, Cell Health, Heart Health, Brain Health, Antioxidant Protection – Non-GMO, Gluten-Free, Vegetarian – 100 Capsules

Life Extension

1,657 Amazon reviews

9.2/10

(1,657)

IngredientDecaffeinated Green Tea Extract (standardized to 98% Polyphenols, 45% EGCg)

Dose725mg green tea extract (326mg EGCg) per capsule

FormCapsule

TestingThird-Party Tested

725mg green tea extract (326mg EGCg) per capsuleClinical range: 250-500mg EGCG daily (from 400-800mg GTE)

Clinical dose

$0.23/serving$22.50 · 100 Capsules

Ideal for: high-dose decaffeinated green tea extract

Not ideal for: Those wanting a lower dose or a caffeinated version for energy.

Pros

326mg EGCg per capsule (highest per-cap dose)
98% polyphenol standardization
Decaffeinated (caffeine-free)
Research-driven brand

Cons

Higher price ($0.22/serving)
May cause GI discomfort on empty stomach
High concentration — start with one capsule
Decaf process may alter catechin ratio

Buy Nowon Amazon

Read full Decaffeinated Green Tea Extract (standardized to 98% Polyphenols, 45% EGCg)guide →

NOW Foods Supplements, EGCg Green Tea Extract 400 mg, Free Radical Scavenger*, 90 Veg Capsules

NOW Foods

5,555 Amazon reviews

9/10

(5,555)

Delivers 200mg EGCG per capsule from an extract standardized to 50% EGCg and 80% total catechins — among the highest standardization on the market. At $0.10/serving, it offers exceptional value. GMP-certified with third-party testing. Two capsules provide the optimal 400mg EGCG dose used in many clinical trials.

IngredientGreen Tea Extract (standardized to 80% Total Catechins, 50% EGCg)

Dose400mg green tea extract (200mg EGCg) per capsule

FormCapsule

TestingGMP Certified, Third-Party Tested

400mg green tea extract (200mg EGCg) per capsuleClinical range: 250-500mg EGCG daily (from 400-800mg GTE)

Therapeutic dose

$0.12/serving

Ideal for: overall green tea extract

Not ideal for: Caffeine-sensitive individuals who need a decaf option.

Pros

50% EGCg standardization
Best value at $0.10/serving
GMP-certified, third-party tested
80% total catechin content

Cons

Contains caffeine
May need 2 capsules for full clinical dose
No enteric coating
Caffeine amount not specified on label

Buy Nowon Amazon

Read full Green Tea Extract (standardized to 80% Total Catechins, 50% EGCg)guide →

Jarrow Formulas® Green Tea Herbal Antioxidant 500 mg, Dietary Supplement, Cardiovascular and Immune Health, 100 Capsules, 100 Day Supply

Jarrow Formulas

1,882 Amazon reviews

8.6/10

(1,882)

Provides 500mg of water-extracted green tea with 50% polyphenol standardization at an excellent price point. Jarrow Formulas uses a water-based extraction method that avoids harsh chemical solvents. Good balance of potency and value for daily antioxidant support. Available in both caffeinated and decaf versions.

IngredientGreen Tea Extract (standardized to 50% Polyphenols)

Dose500mg green tea extract (250mg polyphenols) per capsule

FormCapsule

TestingThird-Party Tested

500mg green tea extract (250mg polyphenols) per capsuleClinical range: 250-500mg EGCG daily (from 400-800mg GTE)

Therapeutic dose

$0.17/serving$17.14 · 100 Capsules

Ideal for: affordable decaffeinated green tea extract

Not ideal for: Those wanting the highest EGCG concentration per capsule.

Pros

Water-extracted (no harsh solvents)
Good value at $0.12/serving
500mg per capsule
Decaf option available

Cons

Lower standardization (50% polyphenols)
EGCG content not separately specified
May need 2 capsules for full effect
Less concentrated than competitors

Buy Nowon Amazon

Read full Green Tea Extract (standardized to 50% Polyphenols)guide →

Pairs Well With

Frequently taken together based on complementary benefits

Quercetin

Sunergetic Quercetin Bromelain 1000mg

1,000mg quercetin per 2-capsule serving; 30 servings per bottle

(806)$0.60/serving

Buy Nowon Amazon

Turmeric / Curcumin

Integrative Therapeutics Curcumax Pro

2 capsules twice daily

(218)$0.82/serving

Buy Nowon Amazon

Browse all supplement comparisons →

How to Choose

Understanding EGCG Standardization

Green tea extracts are standardized to various compounds: total polyphenols, total catechins, or specifically EGCG. The most useful metric is EGCG content per serving, as EGCG is the catechin with the strongest clinical evidence. Look for products that list EGCG separately on the Supplement Facts panel. A good benchmark is 200-400mg EGCG per serving.

Caffeinated vs Decaffeinated Extracts

Standard green tea extract retains natural caffeine (typically 20-50mg per capsule). Decaffeinated versions remove 95%+ of caffeine while preserving catechins. Choose decaf if you take green tea extract in the afternoon/evening, are caffeine-sensitive, or already consume caffeine from other sources. Both forms deliver equivalent EGCG benefits.

Liver Safety Considerations

High-dose green tea extract (especially on an empty stomach) has been associated with rare cases of liver injury. The European Food Safety Authority recommends not exceeding 800mg EGCG daily from supplements. Always take with food, start with a lower dose, and discontinue if you experience symptoms like abdominal pain, dark urine, or jaundice.

Ready to Buy?

Life Extension Mega Green Tea Extract (Decaffeinated)

9.2/10$0.23/servingBest for: high-dose decaffeinated green tea extract

The best green tea extract supplement provides 400-500mg EGCG per serving from a standardized extract, ideally decaffeinated, with third-party testing for catechin content and heavy metals.

Evidence:Meta-analysis (2009) · 11 RCTs · high confidence[#1]

Buy Nowon Amazon

Read Our Full Green Tea Extract Research Guide

Evidence level, dosage, side effects, and more →

Already taking supplements?

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Related Conditions

Inflammation Blood Sugar Management Weight Loss

Learn More

Do Weight Loss Supplements Work?

Frequently Asked Questions

What is the best green tea extract supplement?

NOW Foods EGCg Green Tea Extract 400mg is our top pick for value and standardization, delivering 200mg EGCG at $0.10/serving. For a higher dose and decaf option, Life Extension Mega Green Tea Extract provides 326mg EGCG per capsule. Both are third-party tested.

How much green tea extract should I take daily?

Clinical studies use 200-500mg of EGCG daily for antioxidant and metabolic benefits. The European Food Safety Authority recommends not exceeding 800mg EGCG daily from supplements. Start with one capsule (200-300mg EGCG) and increase if well tolerated. Always take with food.

Evidence:Meta-analysis (2009) · 11 RCTs · high confidence[#1]

Is green tea extract safe for the liver?

At recommended doses (200-500mg EGCG daily) taken with food, green tea extract is safe for most people ^[2]. Rare liver injury cases have been reported, typically at very high doses or on an empty stomach. The European Food Safety Authority set a tolerable upper intake of 800mg EGCG/day from supplements ^[2]. Take with food, stay within recommended doses, and stop use if you experience abdominal pain, dark urine, or yellowing of skin/eyes.

Evidence:Review (2018) · high confidence[#2]

Continue Reading

Supplement Guide

References

Meta-analysisHursel R, Viechtbauer W, Westerterp-Plantenga MS (2009). The effects of green tea on weight loss and weight maintenance: a meta-analysis. International Journal of Obesity. DOI PubMed
ReviewEFSA Panel on Food Additives and Nutrient Sources (2018). Scientific opinion on the safety of green tea catechins. EFSA Journal. DOI