EGCG (Green Tea Extract)
The main bioactive in green tea. Powerful antioxidant with metabolic and cancer-prevention signals — but high-dose extracts carry real liver risk.
Strong epidemiological evidence linking green tea consumption to cardiovascular and cancer outcomes. Moderate trial evidence for modest weight loss, lipid improvement, blood pressure reduction, and anti-inflammatory effects. Anti-cancer effects shown in animal models and observational data.
EGCG (epigallocatechin gallate) is the most abundant and most active catechin in green tea. It's a potent antioxidant and signals through multiple longevity-relevant pathways — modulating mTOR, AMPK, and several gene expression programs. Population studies link green tea consumption to reduced cardiovascular disease, certain cancers, and overall mortality. High-dose concentrated extracts deliver more EGCG than tea drinking ever could, which is both the point and the risk: concentrated EGCG has caused liver toxicity in some users. Drinking green tea is essentially risk-free. Taking extracts requires more care.
- Form
- Standardised green tea extract with EGCG content specified (usually 45–98%). Decaffeinated versions exist if caffeine is an issue. Drinking green tea is the safest delivery — 2–4 cups daily provides meaningful EGCG with no toxicity risk.
- Dose
- Standardised extract: 300–500 mg EGCG/day. Don't exceed 800 mg/day (liver toxicity ceiling per EFSA review). Tea drinkers: 2–4 cups of high-quality green tea daily.
- Timing
- Take with food — empty-stomach concentrated EGCG is most strongly associated with liver toxicity. AM typical.
- Schedule
- Daily. Periodic breaks (1–2 weeks every few months) optional.
- Side effects
- Liver toxicity is the major concern — usually with concentrated extracts on empty stomach. Symptoms: jaundice, dark urine, abdominal pain — stop and see a doctor. GI upset, headache, insomnia (from caffeine in non-decaf versions).
- Interactions
- Iron — EGCG significantly reduces non-heme iron absorption; separate by 2 hours. Anticoagulants — mild additive blood-thinning. Statins, calcium channel blockers — CYP enzyme interactions. Bortezomib (cancer drug) — EGCG opposes its action; avoid.
- Contraindications
- Pre-existing liver disease. History of EGCG-related liver injury. Iron deficiency anemia (relative). Pregnancy (limited safety data for concentrated extracts).
- Lab markers
- Liver enzymes (ALT, AST) at baseline and 8–12 weeks of high-dose extract use.
- Food sources
- Green tea (matcha is the highest), white tea, oolong tea. Black tea has much less. 2–4 cups daily of brewed green tea is the safest, most-validated way to consume EGCG.
Pairs with
Quercetin (synergistic polyphenol). Curcumin, resveratrol (longevity polyphenol stack). Caffeine (naturally combined in green tea; additive metabolic effect).
within Polyphenols & antioxidants