EGCG
Evidence Fact Sheet
Epigallocatechin Gallate
EGCG (epigallocatechin gallate) is the major green-tea catechin, studied as an antioxidant and metabolic compound acting via NRF2/HO-1, AMPK and DNMT pathways. Human research doses run ~270-800 mg/day; EFSA sets an 800 mg/day safety ceiling due to hepatotoxicity. Evidence is modest, with honest null findings.
Also known as: EGCG · Epigallocatechin Gallate · Green Tea Extract (EGCG-standardized) · Teavigo
Overview
EGCG (epigallocatechin gallate) is the most abundant and most studied catechin in green tea (Camellia sinensis), sold as an isolated standardized extract (e.g. Teavigo) or as green-tea catechin blends. Mechanistic research centers on direct free-radical scavenging and metal-ion chelation, NRF2/HO-1 antioxidant-pathway activation, AMPK-related lipid-metabolism modulation, and in-vitro DNMT (epigenetic) effects, though low oral bioavailability makes human relevance of some pathways uncertain. Human studies commonly use 400-800 mg EGCG/day for 8-12 weeks (weight-management work uses ~270-800 mg/day, often with caffeine); EFSA 2018 set a hard safety ceiling of ≤800 mg EGCG/day above which hepatotoxicity risk rises. Regulatory status: green-tea catechins hold an FDA GRAS notice and EGCG is sold under DSHEA, but EFSA authorized no health claim and NIH LiverTox lists green-tea extract as a cause of liver injury; "liver-protective/hepatoprotective" framing is prohibited because EGCG itself is hepatotoxic.
Mechanism of Action
Direct free-radical scavenging and metal-ion chelation (research context: in vitro and human oxidative-stress markers such as MDA / lipid peroxidation) · NRF2 / HO-1 antioxidant-pathway activation (mechanistic research context) · AMPK pathway modulation and lipid-metabolism-related research (animal plus human metabolic endpoints) · DNMT (DNA methyltransferase) activity modulation, an epigenetic mechanism studied mainly in vitro (IC50 ~0.5-5 microM); oral bioavailability is low and whether effective human concentrations are reached is uncertain, so this stays at the mechanism/education level · OATP-transporter inhibition and related pharmacokinetic-interaction research
Body systems: DNA & Epigenetic · Cardiovascular · Cellular Renewal
Evidence-Based Benefits
Each benefit below is anchored to a specific PubMed-indexed study. Effect sizes, sample sizes, and p-values are reported as published; no values are inferred. Honest negatives and null results are kept alongside the positive findings, and disease-research populations are described as such — EGCG is not characterized as a treatment for any disease.
Glycemic Control (EGCG-Specific)
Meta-analysis supported- 41 RCTstrials pooled
- WMD −0.18%HbA1c · p=0.029
- WMD −0.50fasting insulin · p=0.313 (NS)
A meta-analysis of randomized trials pooling EGCG specifically (not just mixed green tea) found statistically significant but small reductions in fasting glucose, HbA1c and HOMA-IR, while the effect on fasting insulin was not significant. The authors explicitly conclude the evidence does not strongly support EGCG as a stand-alone glycemic intervention — an honest, modest-effect framing.
Reported effect: HbA1c WMD −0.18% (95% CI −0.35, −0.02; P=0.029); fasting insulin WMD −0.50 (95% CI −1.46, 0.47; P=0.313), not significant; 41 RCTs included
“EGCG supplementation led to statistically significant, but modest, reductions in fasting blood glucose (FBG), HbA1c, and HOMA-IR. ... the reduction in HbA1c (WMD: -0.18%, 95% CI: -0.35, -0.02; P = 0.029) was small and may not equate to clinically meaningful benefits ... the effect on fasting insulin was not statistically significant (WMD: -0.50; 95% CI: -1.46, 0.47; P = 0.313) ... current evidence does not strongly support the use of EGCG as a stand-alone intervention for glycemic control.”
Source: PMID 40885603 · Saadh 2025 · Clin Ther
Blood Lipids (Total & LDL Cholesterol)
Meta-analysis supported- 14 RCTstrials · 1136 subjects
- −7.20 mg/dLtotal cholesterol · p<0.001
- −2.19 mg/dLLDL-C · p<0.001
A meta-analysis of 14 randomized controlled trials (1136 subjects) found green tea intake significantly lowered fasting total and LDL cholesterol versus control. The absolute reductions are small, consistent with a modest lipid effect. Note these trials largely used green tea / mixed catechins rather than isolated EGCG.
Reported effect: Total cholesterol −7.20 mg/dL (95% CI −8.19, −6.21; P<0.001); LDL cholesterol −2.19 mg/dL (95% CI −3.16, −1.21; P<0.001); 14 RCTs, 1136 subjects
“Green tea consumption significantly lowered the TC concentration by 7.20 mg/dL (95% CI: -8.19, -6.21 mg/dL; P < 0.001) ... significantly lowered the LDL-cholesterol concentration by 2.19 mg/dL (95% CI: -3.16, -1.21 mg/dL; P < 0.001) ... Fourteen eligible randomized controlled trials with 1136 subjects were enrolled”
Source: PMID 21715508 · Zheng 2011 · Am J Clin Nutr
Blood Pressure
Meta-analysis supported- 13 RCTstrials pooled
- −2.08 mmHgsystolic BP
- −1.71 mmHgdiastolic BP
A systematic review and meta-analysis of 13 randomized controlled trials found green tea catechin consumption significantly reduced both systolic and diastolic blood pressure versus control. Effect sizes are small (about 2 mmHg systolic). As with the lipid data, included trials used green tea catechins rather than isolated EGCG.
Reported effect: Systolic BP −2.08 mmHg (95% CI −3.06, −1.05); diastolic BP −1.71 mmHg (95% CI −2.86, −0.56); 13 RCTs
“Green tea consumption significantly changed systolic blood pressure, by -2.08 mm Hg (95% CI -3.06, -1.05), and diastolic blood pressure, by -1.71 mm Hg (95% CI -2.86, -0.56)”
Source: PMID 24861099 · Khalesi 2014 · Eur J Nutr
Weight Management / Body Weight
Meta-analysis supported- 11 articlesstudies pooled
- −1.31 kgbody weight · p<0.001
- p=0.04ethnicity × caffeine interaction
A meta-analysis pooling catechin trials reported a small but significant decrease in body weight and help maintaining weight after weight loss. High habitual caffeine intake appeared to blunt the effect but did not reach significance, and the interaction of ethnicity and caffeine was a significant moderator. The authors frame this as a small positive effect, not a stand-alone weight-loss solution.
Reported effect: Body weight −1.31 kg (P<0.001); 11 articles included; ethnicity × caffeine interaction a significant moderator (P=0.04); high caffeine inhibition not significant (P=0.09)
“Catechins significantly decreased body weight and significantly maintained body weight after a period of WL (=-1.31 kg; P<0.001). ... Inhibition of this effect by high habitual caffeine intake (>300 mg per day) failed to reach significance (=-0.27 kg for high and =-1.60 kg for low habitual caffeine intake; P=0.09). ... Interaction of ethnicity and caffeine intake was a significant moderator (P=0.04).”
Source: PMID 19597519 · Hursel 2009 · Int J Obes
Cognitive Decline (APOE-E4, PENSA RCT)
Null / no benefit RCT supported- 129 participants12-month RCT
- 5-6 mg/kgEGCG dose
- p=0.061PACC-exe · not significant
In the PENSA double-blind RCT, 129 APOE-e4 carriers with subjective cognitive decline received a 12-month multimodal lifestyle intervention plus EGCG (5-6 mg/kg) or placebo. On the primary cognitive composite (PACC-exe), EGCG added no statistically significant benefit over the lifestyle intervention alone (p=0.061) — an honest negative on the primary endpoint, though some secondary and post-washout signals appeared.
Reported effect: Primary outcome PACC-exe adjusted mean difference 0.12 (95% CI −0.01, 0.24; p=0.061), not significant; n=129; EGCG 5-6 mg/kg for 12 months
“After 12 months, no statistically significant difference was observed between MLI+EGCG and MLI+placebo in the PACC-exe (adjusted mean difference [AMD]: 0.12; 95%CI: -0.01, 0.24; p=0.061).”
Source: PMID 40664536 · Forcano 2025 · J Prev Alzheimers Dis
Dosage (research context · not a recommendation)
Antioxidant/anti-inflammatory, lipid and glycemic human studies commonly use 400-800 mg EGCG/day for 8-12 weeks; weight-management studies use 270-800 mg EGCG/day (often combined with 80-300 mg caffeine); skin UV-protection studies use ~540 mg EGCG/day (1080 mg green-tea catechins) for 12 weeks; acute cognition studies use 300-400 mg EGCG. The hard safety ceiling is <=800 mg EGCG/day (EFSA 2018); above this dose hepatotoxicity risk rises significantly. Educational reference, not a dosing recommendation.
Regulatory Status · 4 Markets
- US · FDA
- Green tea catechins hold an FDA GRAS notice (GRN 259, catechins from green tea extract); EGCG is sold as a DSHEA dietary supplement with structure/function claims permitted (30-day notification + disclaimer). Safety caveat: NIH LiverTox lists green tea extract / EGCG as a known cause of liver injury and USP places it in Class B. 'Liver-protective / hepatoprotective' framing and disease/anti-cancer claims are prohibited.
- EU · EFSA
- Permitted supplement ingredient (Directive 2002/46/EC) but with no authorized health claim (all 2010-2011 applications rejected); safety upper limit <=800 mg EGCG/day (EFSA 2018, EFSA Journal 2018;16(4):5239); several countries (e.g. France's ANSES) recommend labeling hepatotoxicity risk and a high-dose-on-empty-stomach warning. China SAMR: tea polyphenols are a health-food raw material with approved 'antioxidant' and 'assists in lowering blood lipids' claims.
- CN · China
- China SAMR: tea polyphenols / green tea extract are common-food + registered health-food raw materials; multiple health foods carry registered antioxidant and assist-lowering-blood-lipids functions. No statutory EGCG dose limit (EFSA 800 mg/day used as internal benchmark).
- BR · ANVISA
- Food supplement (RDC 243/2018 + IN 28/2018 positive list); antioxidant-related claims permitted; must carry an adverse-effect warning and a take-with-food instruction.
Safety
Hepatotoxicity is the first hard red line: EFSA 2018 set a <=800 mg EGCG/day ceiling, above which hepatocellular-injury cases (ALT/AST rising 10-100 fold, latency 1-6 months) increase significantly; USP lists it as Class B, NIH LiverTox includes it, and rare liver-transplant/death cases exist. Any description must co-present the dose ceiling plus 'take with food' (high doses on an empty stomach worsen the risk). EGCG also strongly chelates non-heme iron (reducing iron absorption 30-70%, so anemia/pregnancy warrant caution); it has a pharmacokinetic interaction with OATP substrates such as nadolol; and supplement safety data in pregnancy/lactation are insufficient, so it is not recommended. A critical safety boundary: 'liver-protective / hepatoprotective' claims are absolutely prohibited (because EGCG itself is hepatotoxic, any liver-support / liver-enzyme-lowering framing is seriously misleading).
Related
Goals: weight-management · heart-health
Lifestyles: intermittent-fasting
References
PubMed-indexed citations anchoring the benefit findings above. Effect sizes are reported as published.
- PMID 40885603 · Saadh 2025 · Clin Ther — Glycemic Control (EGCG-Specific)
- PMID 21715508 · Zheng 2011 · Am J Clin Nutr — Blood Lipids (Total & LDL Cholesterol)
- PMID 24861099 · Khalesi 2014 · Eur J Nutr — Blood Pressure
- PMID 19597519 · Hursel 2009 · Int J Obes — Weight Management / Body Weight
- PMID 40664536 · Forcano 2025 · J Prev Alzheimers Dis — Cognitive Decline (APOE-E4, PENSA RCT)
Frequently Asked Questions
1. Is EGCG the same as drinking green tea?
EGCG is the single most abundant catechin in green tea, but supplements provide it as a concentrated standardized extract. Importantly, much of the human trial evidence for lipids, blood pressure and weight (e.g. the Zheng 2011, Khalesi 2014 and Hursel 2009 meta-analyses) used green tea or mixed catechins rather than isolated EGCG, so those results reflect green-tea catechins broadly, not purified EGCG alone. The EGCG-specific glycemic meta-analysis (Saadh 2025) is one of the few that pooled isolated EGCG.
2. How strong is the evidence for metabolic benefits?
Consistently modest. The pooled effects are real but small — for example total cholesterol fell about 7.20 mg/dL and systolic blood pressure about 2.08 mmHg, and the EGCG-specific glycemic meta-analysis found only a −0.18% HbA1c change while the fasting-insulin effect was not significant. Authors of that analysis explicitly state the evidence does not strongly support EGCG as a stand-alone intervention for glycemic control.
3. Does EGCG help cognition?
The evidence is not supportive on primary endpoints. In the PENSA RCT of 129 APOE-e4 carriers, adding EGCG (5-6 mg/kg) to a 12-month lifestyle program produced no statistically significant difference versus placebo on the primary cognitive composite (p=0.061). This is an honest negative result, even though some secondary signals were reported.
4. What is the main safety concern with EGCG?
Hepatotoxicity. EFSA set a safety ceiling of ≤800 mg EGCG/day in 2018, and NIH LiverTox lists green-tea extract as a recognized cause of liver injury. Because EGCG itself can be hepatotoxic, any 'liver-protective' or 'hepatoprotective' framing is prohibited and misleading. EGCG also chelates non-heme iron (reducing iron absorption) and has a pharmacokinetic interaction with certain OATP-substrate drugs, and supplement use in pregnancy/lactation is not recommended due to insufficient safety data.
Last evidence review: 2026-06-13