EGCG / Green Tea
Also sold as: Epigallocatechin gallate · Green tea catechins · Camellia sinensis
EGCG is a green-tea catechin found in brewed tea and concentrated extracts. Small metabolic effects coexist with a distinct liver-injury concern for high-dose extract supplements.
Focus
Community
Not enough ratings yet: 0 of 10
Scores appear after 10 ratings, so that one or two reports can't dominate. Tried it? Your rating counts.
Research
- Focus: Human focus or Alzheimer efficacy is unestablished; the indexed neuroprotection review uses animal models, not human RCTs.
REALITY CHECK // A short fat-oxidation signal is not evidence that EGCG melts body fat, and Alzheimer-model studies do not establish human focus benefits. Brewed tea and concentrated extracts have different exposure patterns and liver-risk profiles. The 800 mg/day liver-enzyme signal is not a guarantee of safety below 800 mg.
Levels: how we grade evidence. Grey = evidence of no benefit; amber = evidence it makes this goal worse.
Ratings are self-reported by a self-selected group of users: how it felt, not proof that it works.
Check your bottle
Compare what your label says with what was used in trials. This is a trial range, not a personal prescription.
Enter the amount from your label to see the result.
How it was studied
UPPER LIMIT // EFSA did not establish a safe supplemental EGCG intake. At or above 800 mg/day, supplement trials showed increased ALT; 800 mg is a hazard signal, not a safe UL. Liver injury may occur below a threshold. Both numerical UL fields therefore remain null.
Summary
Green-tea catechin studies suggest small changes in fat oxidation, LDL, blood pressure and glucose, with no established major weight-loss or cancer-prevention effect. The cognitive claim is preclinical. Concentrated extracts can cause liver injury; higher absorption on an empty stomach is a safety disadvantage, not a reason to seek it.
Mechanism
Catechins affect redox signaling and metabolic pathways; caffeine can contribute to thermogenesis in mixed products. Antioxidant and animal neuroprotection mechanisms do not establish lifespan or cognitive benefits in humans.
Typical studied dose
The dossier describes usual brewed-tea exposure around 90-300 mg EGCG/day and extract labels commonly supplying 100-225 mg EGCG, but gives no universal efficacy-trial target. A high-dose trial used 843 mg/day; that is a liver-safety exposure, not a suggested dose.
Upper limit
EFSA did not establish a safe supplemental EGCG intake. At or above 800 mg/day, supplement trials showed increased ALT; 800 mg is a hazard signal, not a safe UL. Liver injury may occur below a threshold. Both numerical UL fields therefore remain null.
Popular stacks with EGCG / Green Tea
Not enough stack data yet. A combination with EGCG / Green Tea appears here once 5 people rate the same set.
Forms and label traps
| Form on label | Active content | Studied range / day | Absorption & GI tolerance | Verdict |
|---|---|---|---|---|
| Brewed green tea Best for: Ordinary beverage use. |
Unstandardized: active content unknown | no comparable trial range | Lower, variable catechin exposure spread across drinking occasions; ordinary infusion differs from concentrated bolus extracts. Generally tolerated at customary intake; caffeine sensitivity varies. |
Good option GOOD Brewing, leaf quantity and steeping change EGCG content. The dossier reports usual exposure 90-300 mg/day, not a validated grams-of-leaf conversion. |
| EGCG-standardized extract Best for: Label-based risk review, not routine escalation. |
Unstandardized: active content unknown | no comparable trial range | Fasting raises catechin exposure and can increase liver risk; formulation percentage is product-specific. High doses can cause GI symptoms and liver injury. |
Caution CAUTION Products vary widely in total catechins and EGCG; 45-98% catechins is not necessarily 45-98% EGCG. No universal efficacy range or fraction is inferred. |
| Decaffeinated green tea extract Best for: People needing to identify hidden caffeine. |
Unstandardized: active content unknown | no comparable trial range | Removing caffeine does not establish lower catechin-related liver risk. May reduce caffeine-related stimulation; extract risks persist. |
Caution CAUTION Confirm separate EGCG and caffeine quantities. This is not a distinct proven efficacy dose. |
| Liposomal EGCG Best for: Research and claim verification. |
Unstandardized: active content unknown | no comparable trial range | The claimed tenfold bioavailability advantage is unverified in the supplied dossier. Comparative human tolerance is unknown. |
Caution CAUTION A 52 mg label cannot be multiplied by ten to invent equivalence with a larger conventional dose. |
Common label traps
- TRAP_01 // 800 mg is a safe daily limit
It is a liver-enzyme hazard signal, and EFSA did not establish a safe supplemental level. Numerical UL must not be set to 800 mg. - TRAP_02 // Take it fasting for maximum absorption
Fasting raises catechin exposure and liver risk. Absorption enhancement is not automatically a clinical advantage. - TRAP_03 // Liposomal means ten times the benefit
The dossier cannot substantiate the tenfold claim or a clinical dose equivalence. - TRAP_04 // Antioxidant means longevity or cancer protection
Mechanisms and inconsistent observational cancer data cannot establish these outcomes. - TRAP_05 // EGCG needs 5-HTP to deliver neurotransmitters to the brain
No credible human protocol supporting this pairing is supplied; do not turn biochemical speculation into a stack instruction.
Other outcomes studied
Outside the five leaderboard goals. Same evidence levels as above.
- FAT_OXIDATION Limited · benefit
A human systematic review/meta-analysis suggests small, heterogeneous energy-expenditure and fat-oxidation changes, often with caffeine; durable clinically meaningful weight loss is not established.
PMID 27883924 - LDL_CHOLESTEROL Limited · benefit
A human systematic review suggests LDL lowering of only a few mg/dL; the dossier does not supply a robust universal magnitude.
PMID 27324590 - BLOOD_PRESSURE Moderate · benefit
RCT catechin syntheses suggest small blood-pressure changes of a few mmHg. The broader flavonoid review is not an isolated-EGCG trial and should not define its dose.
PMID 24861099 PMID 35955475 - GLYCEMIA Limited · benefit
Meta-analyses report small fasting-glucose/glycemic-index signals, while some HbA1c/insulin results are nonsignificant. Green-tea catechin mixtures and isolated EGCG are not identical interventions.
PMID 23426037 PMID 40885603 - CANCER_PREVENTION Limited · no benefit
Cochrane finds inconsistent/insufficient prevention evidence. Liver and breast cancer associations are largely observational and cannot establish causality or capsule benefits.
PMID 32118296 PMID 19588362 PMID 26412579 PMID 29876987 - NEUROPROTECTION No established evidence
The systematic review concerns Alzheimer animal models. Human cognitive or Alzheimer efficacy is unestablished; this is not a negative human RCT.
PMID 32942205 - LIVER_INJURY Moderate · makes it worse
EFSA safety review and USP hepatotoxicity review identify extract-related liver injury. High-dose trial work at 843 mg/day examines genetic susceptibility; the 800 mg/day signal must not be presented as a safe threshold.
PMID 32625874 PMID 32140423 PMID 36178169
Reader questions
How much EGCG is safe for the liver?
No universally safe supplemental dose was established by EFSA. The signal at or above 800 mg/day concerns harm, not permission to take 799 mg. Concentration, fasting and individual susceptibility matter.
Empty stomach or food?
Concentrated extracts should not be taken fasting: exposure rises and may increase hepatotoxicity risk. Stop and seek medical review for liver warning signs.
Does decaf or liposomal avoid the risk?
Decaf removes caffeine rather than catechin risk. A liposomal tenfold claim is unverified here and cannot justify dose multiplication or assumed safety.
Does tea block iron?
The dossier reports conflicting tea-polyphenol and isolated-EGCG results. With iron deficiency, separate tea/extract from iron-rich meals or supplements and follow clinical monitoring.
Can I combine it with a beta-blocker or chemotherapy?
Nadolol exposure can fall in human studies. Bortezomib antagonism is preclinical but consequential enough to require oncology review; do not create an unsupervised stack.
Stack interactions
- Caution Nadolol [CAUTION]
Human volunteer pharmacokinetic data support reduced nadolol absorption/exposure; rat studies explore transporter mechanisms. Review with the prescriber rather than assuming a timing interval solves it.
PMID 29480324 PMID 23920278 PMID 34303263 - Caution Bortezomib / oncology treatment [CAUTION]
Laboratory and animal studies show antagonism of boronic-acid proteasome inhibitors. Clinical event magnitude is unknown, but unsupervised concentrated EGCG should be avoided during treatment and discussed with oncology.
PMID 19190249 PMID 21400028 PMID 26471237 - Caution Fexofenadine [CAUTION]
A healthy-volunteer pharmacokinetic study found markedly reduced fexofenadine exposure, but not pseudoephedrine exposure.
PMID 35678032 - Caution Iron supplements / iron deficiency [CAUTION]
The dossier reports inhibition by tea polyphenols but a null isolated-EGCG absorption trial. These catalog entries have no titles, so source records are withheld; separation by roughly two hours is a precaution, not a proven universal interaction interval. - Caution Caffeine [CAUTION]
Check whether the extract is decaffeinated. Caffeine can contribute to thermogenesis and cause stimulation or sleep disruption; do not attribute the whole mixture effect to EGCG.
Red flags: interactions and who should avoid it
Interactions
Human pharmacokinetic studies show lower nadolol and fexofenadine exposure with green-tea constituents. Bortezomib antagonism is preclinical but warrants oncology review and avoiding unsupervised extracts. Tea polyphenol/iron effects conflict with an isolated-EGCG trial in the dossier; separate from iron when deficient as a precaution. Caffeine changes stimulation and sleep effects.
Avoid or ask a doctor first if
Avoid concentrated extracts with liver disease, raised liver enzymes, pregnancy/breastfeeding or unsupervised childhood use. Review nadolol and cancer therapy first. Do not take high-dose extracts fasting. Stop and seek urgent medical review for jaundice, dark urine, right-upper-abdominal pain or marked weakness.
Sources (PubMed, 21)
- Physiological effects of epigallocatechin-3-gallate (EGCG) on energy expenditure for prospective fat oxidation in humans: A systematic review and meta-analysis.
PMID 27883924 · 2017 · systematic review / meta-analysisA human systematic review/meta-analysis suggests small, heterogeneous energy-expenditure and fat-oxidation changes, often with caffeine; durable clinically meaningful weight loss is not established.
- Systematic review of green tea epigallocatechin gallate in reducing low-density lipoprotein cholesterol levels of humans.
PMID 27324590 · 2016 · systematic review / meta-analysisA human systematic review suggests LDL lowering of only a few mg/dL; the dossier does not supply a robust universal magnitude.
- Green tea catechins and blood pressure: a systematic review and meta-analysis of randomised controlled trials.
PMID 24861099 · 2014 · systematic review / meta-analysisRCT catechin syntheses suggest small blood-pressure changes of a few mmHg. The broader flavonoid review is not an isolated-EGCG trial and should not define its dose.
- Effects of the Treatment with Flavonoids on Metabolic Syndrome Components in Humans: A Systematic Review Focusing on Mechanisms of Action.
PMID 35955475 · 2022 · systematic review / meta-analysisRCT catechin syntheses suggest small blood-pressure changes of a few mmHg. The broader flavonoid review is not an isolated-EGCG trial and should not define its dose.
- Effects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials.
PMID 23426037 · 2013 · systematic review / meta-analysisMeta-analyses report small fasting-glucose/glycemic-index signals, while some HbA1c/insulin results are nonsignificant. Green-tea catechin mixtures and isolated EGCG are not identical interventions.
- Effect of Epigallocatechin Gallate on Glycemic Index: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
PMID 40885603 · 2025 · systematic review / meta-analysisMeta-analyses report small fasting-glucose/glycemic-index signals, while some HbA1c/insulin results are nonsignificant. Green-tea catechin mixtures and isolated EGCG are not identical interventions.
- Green tea (Camellia sinensis) for the prevention of cancer.
PMID 32118296 · 2020 · systematic review / meta-analysisCochrane finds inconsistent/insufficient prevention evidence. Liver and breast cancer associations are largely observational and cannot establish causality or capsule benefits.
- Green tea (Camellia sinensis) for the prevention of cancer.
PMID 19588362 · 2009 · systematic review / meta-analysisCochrane finds inconsistent/insufficient prevention evidence. Liver and breast cancer associations are largely observational and cannot establish causality or capsule benefits.
- Green tea and liver cancer risk: A meta-analysis of prospective cohort studies in Asian populations.
PMID 26412579 · 2016 · systematic review / meta-analysis of observational studiesCochrane finds inconsistent/insufficient prevention evidence. Liver and breast cancer associations are largely observational and cannot establish causality or capsule benefits.
- The association between green tea consumption and breast cancer risk: A systematic review and meta-analysis.
PMID 29876987 · 2018 · systematic review / meta-analysisCochrane finds inconsistent/insufficient prevention evidence. Liver and breast cancer associations are largely observational and cannot establish causality or capsule benefits.
- The pharmacological activity of epigallocatechin-3-gallate (EGCG) on Alzheimer's disease animal model: A systematic review.
PMID 32942205 · 2020 · preclinical systematic review / experimental studyThe systematic review concerns Alzheimer animal models. Human cognitive or Alzheimer efficacy is unestablished; this is not a negative human RCT.
- Scientific opinion on the safety of green tea catechins.
PMID 32625874 · 2018 · narrative reviewEFSA safety review and USP hepatotoxicity review identify extract-related liver injury. High-dose trial work at 843 mg/day examines genetic susceptibility; the 800 mg/day signal must not be presented as a safe threshold.
- United States Pharmacopeia (USP) comprehensive review of the hepatotoxicity of green tea extracts.
PMID 32140423 · 2020 · systematic review / meta-analysisEFSA safety review and USP hepatotoxicity review identify extract-related liver injury. High-dose trial work at 843 mg/day examines genetic susceptibility; the 800 mg/day signal must not be presented as a safe threshold.
- Hepatotoxicity with High-Dose Green Tea Extract: Effect of Catechol-O-Methyltransferase and Uridine 5'-Diphospho-glucuronosyltransferase 1A4 Genotypes.
PMID 36178169 · 2023 · randomized controlled trialEFSA safety review and USP hepatotoxicity review identify extract-related liver injury. High-dose trial work at 843 mg/day examines genetic susceptibility; the 800 mg/day signal must not be presented as a safe threshold.
- Role of (-)-epigallocatechin gallate in the pharmacokinetic interaction between nadolol and green tea in healthy volunteers.
PMID 29480324 · 2018 · randomized controlled trialHuman volunteer pharmacokinetic data support reduced nadolol absorption/exposure; rat studies explore transporter mechanisms. Review with the prescriber rather than assuming a timing interval solves it.
- Effects of green tea extract and (-)-epigallocatechin-3-gallate on pharmacokinetics of nadolol in rats.
PMID 23920278 · 2013 · animal studyHuman volunteer pharmacokinetic data support reduced nadolol absorption/exposure; rat studies explore transporter mechanisms. Review with the prescriber rather than assuming a timing interval solves it.
- Oral epigallocatechin gallate reduces intestinal nadolol absorption via modulation of Oatp1a5 and Oct1 transcriptional levels in spontaneously hypertensive rats.
PMID 34303263 · 2021 · animal studyHuman volunteer pharmacokinetic data support reduced nadolol absorption/exposure; rat studies explore transporter mechanisms. Review with the prescriber rather than assuming a timing interval solves it.
- Green tea polyphenols block the anticancer effects of bortezomib and other boronic acid-based proteasome inhibitors.
PMID 19190249 · 2009 · animal studyLaboratory and animal studies show antagonism of boronic-acid proteasome inhibitors. Clinical event magnitude is unknown, but unsupervised concentrated EGCG should be avoided during treatment and discussed with oncology.
- Preclinical evaluation of the antitumor activity of bortezomib in combination with vitamin C or with epigallocatechin gallate, a component of green tea.
PMID 21400028 · 2011 · preclinical systematic review / experimental studyLaboratory and animal studies show antagonism of boronic-acid proteasome inhibitors. Clinical event magnitude is unknown, but unsupervised concentrated EGCG should be avoided during treatment and discussed with oncology.
- EGCG antagonizes Bortezomib cytotoxicity in prostate cancer cells by an autophagic mechanism.
PMID 26471237 · 2015 · in vitro studyLaboratory and animal studies show antagonism of boronic-acid proteasome inhibitors. Clinical event magnitude is unknown, but unsupervised concentrated EGCG should be avoided during treatment and discussed with oncology.
- Exposure of Fexofenadine, but Not Pseudoephedrine, Is Markedly Decreased by Green Tea Extract in Healthy Volunteers.
PMID 35678032 · 2022 · randomized controlled trialA healthy-volunteer pharmacokinetic study found markedly reduced fexofenadine exposure, but not pseudoephedrine exposure.
Community comments
No approved comments yet. Comments are held for moderation.