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Green Tea Extract (EGCG)

Concentrated green tea polyphenols providing powerful antioxidant protection, metabolic support, and anti-aging benefits

Scientific nameCamellia sinensis extract FormulaC22H18O11 (EGCG) Molecular weight458.37 g/mol CAS989-51-5
15 absorption score
8 safety / 10
25 USD per month
5 documented interactions

Check it against something

Evidence level A

Green Tea Extract (EGCG) with:

Compatibility score 82 out of 100
82 out of 100
Works better together Compatible. Timing differs, so follow each supplement's own window.

Check it against your whole stack →

What it does

mechanism and evidence for each claim

Powerful antioxidant protection

Provides potent antioxidant effects protecting cells from damage

EGCG and other catechins neutralize free radicals and reduce oxidative stress Evidence A-grade 2-6 weeks

Weight management and fat burning

Supports weight loss and increases fat oxidation

Increases thermogenesis and fat oxidation through EGCG Evidence A-grade 4-12 weeks

Cardiovascular health support

Improves heart health and reduces cardiovascular risk factors

Improves endothelial function and reduces inflammation Evidence A-grade 6-12 weeks

Brain health and cognitive protection

Supports brain function and may protect against cognitive decline

Crosses blood-brain barrier providing neuroprotective effects Evidence B-grade 8-16 weeks

Cancer prevention support

May help reduce risk of certain types of cancer

Antioxidant and anti-inflammatory effects protect DNA Evidence B-grade Long-term use

Others take these for the same thing

Same goal, different mechanism — check any of them against this one

Turmeric Anti-inflammatory & antioxidant 300-1000mg A 3% Ashwagandha Stress management & energy 300-600mg A 75% Vitamin B12 (Cyanocobalamin) Energy & nerve support 250-1000 mcg A 70% Coenzyme Q10 (CoQ10) Heart health & cellular energy 100-200mg A 10% Phosphorus Bone health & energy metabolism 700-1250mg A 80% Vitamin B3 (Niacinamide) Energy & skin health (no flush) 100-1000 mg A 88%

Every pair we checked

12 combinations scored by the engine
Green Tea Extract (EGCG) + Iron Sulfate Green tea tannins reduce iron absorption Needs attention 52
Green Tea Extract (EGCG) + Caffeine No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Creatine Monohydrate No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Calcium Carbonate No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Whey Protein No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Lactase No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Bovine Collagen No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + DHA No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Turmeric No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Fish Oil (EPA/DHA) No documented interaction either way No known interaction 70
Green Tea Extract (EGCG) + Quercetin Enhanced antioxidant and anti-inflammatory effects Works better together 78
Green Tea Extract (EGCG) + Vitamin D3 Enhanced antioxidant protection and EGCG stability Works better together 82

Dosage

Between meals
Daily200-500mg EGCG
Antioxidant support200-400mg EGCG daily
Weight management300-500mg EGCG daily
Cardiovascular health300-500mg EGCG daily
Maximum safe800mg EGCG daily (upper limit)

Before you take it

VeganYes

When to expect it

First Effects2-4 weeks for antioxidant and metabolic benefits
Peak Benefits8-16 weeks for sustained heart health and anti-aging benefits
Deficiency DevelopmentReturn to baseline antioxidant status
Toxicity OnsetRare, mainly with very high doses

How to measure it

$60-120
MarkerLiver enzymes (ALT, AST) if using high doses
OptimalNormal liver enzyme levels
Deficient belowNot applicable for supplement
FrequencyEvery 6 months if using high doses (>400mg EGCG daily)

What people actually reported to the FDA

CAERS, 67 reports naming it as the suspect

Most reported effects

Vomiting 11
Nausea 9
Dizziness 8
Atrial fibrillation 7
Headache 7
Named as the suspect 67 reports of 79 that mention it at all
Serious outcome 83% hospitalisation, emergency room or worse
Other Serious or Important Medical Event42
Hospitalization29
Visited a Health Care Provider15

Reports are voluntary and unverified — they record what someone experienced while taking something, not what the compound caused. Counts skew towards products people take a lot of, and a serious outcome is more likely to be reported than a mild one, so these are not rates. How we filter them →

What actually reaches you

The label counts the carrier, your body does not
Absorption Low 15 of 100 · poorly absorbed relative to other forms
Delivered daily 52.5 mg
Cost per 100 mg delivered $1.59 comparative — uses the absorption score, not a measured percentage

Works better with

3 documented
+
Vitamin C

Enhanced antioxidant protection and EGCG stability

Vitamin C helps stabilize EGCG and provides complementary antioxidant effects · level A
+
Quercetin

Enhanced antioxidant and anti-inflammatory effects

Both are polyphenols with synergistic antioxidant properties · level B
+
Exercise

Enhanced fat burning and weight loss effects

EGCG amplifies exercise-induced fat oxidation · level A

What not to take with Green Tea Extract (EGCG)

2 documented
!
Iron Supplements

Green tea tannins reduce iron absorption

Polyphenols bind iron reducing bioavailability · moderate significance
!
Milk Dairy

Milk proteins may reduce EGCG absorption

Proteins bind polyphenols reducing absorption · minor significance

Medication interactions

Discuss these with a pharmacist before combining
blood-thinners Moderate

May enhance anticoagulant effects

What to do: Monitor bleeding parameters

stimulant-medications Minor

May enhance stimulant effects due to caffeine

What to do: Monitor for overstimulation

iron-supplements Moderate

May reduce iron absorption

What to do: Separate dosing by 2-3 hours

Available forms

bioavailability compared
Green Tea Extract (50% EGCG) 60
Decaffeinated Green Tea Extract 65

Green Tea Extract (50% EGCG): Proven benefits, Weight support, Heart health, Affordable

Decaffeinated Green Tea Extract: No caffeine, Better tolerance, Same EGCG benefits, Sleep-friendly

Food sources

before you supplement
Green tea (brewed) 50-100mg EGCG per cup · 50
Matcha powder 130-200mg EGCG per serving · 60
White tea 25-50mg EGCG per cup · 45
Green tea extract supplements 100-500mg EGCG per capsule · 60-70

Too little

deficiency signs
  • Increased oxidative stress and cellular damage
  • Poor metabolic function and weight gain
  • Increased cardiovascular risk factors
  • Accelerated aging and inflammation
  • Poor antioxidant protection
  • Increased cancer risk
  • Reduced longevity potential

Too much

toxicity signs
  • Generally safe but potential concerns:
  • Liver enzyme elevation with very high doses (>800mg EGCG)
  • Iron deficiency with excessive use
  • Caffeine-related side effects (jitters, insomnia)
  • Rare allergic reactions

Who benefits most

weight-management-fat-loss

Excellent for supporting weight loss and fat burning

300-500mg EGCG daily
antioxidant-anti-aging

Powerful antioxidant protection against aging and disease

200-400mg EGCG daily
cardiovascular-heart-health

Supports heart health and reduces cardiovascular risk

300-500mg EGCG daily
brain-cognitive-protection

May protect brain health and cognitive function

200-400mg EGCG daily
cancer-prevention

May help reduce cancer risk through antioxidant effects

300-600mg EGCG daily

Where to buy it

compare forms first

Look for Green Tea Extract (EGCG) at 200-500mg EGCG per serving. The form that matters here is Green Tea Extract (50% EGCG).

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What else affects it

Beyond other supplements
+
Exercise

Enhanced fat burning and weight loss effects

EGCG amplifies exercise-induced fat oxidation
!
Milk dairy

Milk proteins may reduce EGCG absorption

Proteins bind polyphenols reducing absorption

How it works

  • EGCG provides potent antioxidant protection against free radicals
  • Increases thermogenesis and fat oxidation for weight management
  • Improves endothelial function and cardiovascular health
  • Anti-inflammatory effects reduce chronic inflammation
  • May inhibit certain enzymes involved in cancer development
  • Supports healthy cholesterol and blood sugar levels

Key findings

what the evidence supports
  • Strong evidence for antioxidant protection and weight management
  • Excellent cardiovascular and metabolic health benefits
  • Generally safe but monitor liver function with very high doses
  • Synergistic with exercise for enhanced fat burning

Sources: NIH Examine.com · data reviewed 2026-08-02

Compiled by Denis, who maintains this database and holds no medical qualification — every figure here is sourced or derived, never asserted. How we calculate it →

Common questions

What are the benefits of Green Tea Extract (EGCG)?

Documented effects: Powerful antioxidant protection; Weight management and fat burning; Cardiovascular health support; Brain health and cognitive protection. Provides potent antioxidant effects protecting cells from damage

How much Green Tea Extract (EGCG) should you take per day?

The common daily range is 200-500mg EGCG. By goal — antioxidant support: 200-400mg EGCG daily; weight management: 300-500mg EGCG daily; cardiovascular health: 300-500mg EGCG daily; maximum safe: 800mg EGCG daily (upper limit).

When is the best time to take Green Tea Extract (EGCG)?

Between meals. First effects are typically reported within 2-4 weeks for antioxidant and metabolic benefits.

What are the side effects of Green Tea Extract (EGCG)?

At excessive doses: Generally safe but potential concerns:, Liver enzyme elevation with very high doses (>800mg EGCG), Iron deficiency with excessive use, Caffeine-related side effects (jitters, insomnia), Rare allergic reactions. Safety rating at normal doses is 8 out of 10.

What should you not take with Green Tea Extract (EGCG)?

Separate it from Iron Supplements, Milk Dairy by two to four hours. Green tea tannins reduce iron absorption

Does Green Tea Extract (EGCG) interact with medications?

Documented interactions with blood-thinners, stimulant-medications, iron-supplements. Discuss these with a pharmacist before combining.

How do you know if you need Green Tea Extract (EGCG)?

The marker is Liver enzymes (ALT, AST) if using high doses, optimal range Normal liver enzyme levels. Common deficiency signs: Increased oxidative stress and cellular damage, Poor metabolic function and weight gain, Increased cardiovascular risk factors, Accelerated aging and inflammation.

Taken for

62 Energy & Metabolism

Vitamin B12 (Methylcobalamin) · Ashwagandha · Vitamin B12 (Cyanocobalamin)

 49 Liver & Detox

Turmeric · Vitamin C (Ascorbic Acid) · D-Mannose