Green Tea Extract
Overview
Green tea extract contains EGCG (C22H18O11) as primary bioactive antioxidant catechin. A meta-analysis of RCTs showed supplementation reduced body weight (−1.78 kg), BMI (−0.65 kg/m²), and waist circumference. Additional evidence supports LDL and blood pressure reduction. Critical safety concern: high-dose EGCG supplements linked to hepatotoxicity (rare but documented). EFSA safety limit: 338 mg EGCG/day from supplements. Contains caffeine; inhibits non-heme iron absorption. Take with food to reduce GI and liver risk.
Dosage
400 mg · Any time · Can take on empty stomach
Key Interactions
15 verified interactions found
Catechin-Plasmaspiegel nach Grüntee-Konsum zeigen hohe interindividuelle Variabilität. Diese Schwankungen beeinflussen sowohl vorteilhafte als auch nachteilige Effekte von Grüntee-Polyphenolen.
Grüntee-Extrakt und isolierte Catechine gleichzeitig erhöhen die Gesamt-Catechinmenge schwer kalkulierbar. Nur eine Catechin-Quelle wählen und EGCG-Tagesmenge unter 800mg halten (EFSA 2018).
View details →Green tea polyphenols interfere with folate absorption mechanisms (Alemdaroglu et al., 2008)
Separate doses by 2+ hours; monitor folate levels if taking folic acid supplementation
View details →Green tea extract contains significant amounts of caffeine (depending on standardization). Combining with additional caffeine supplements risks exceeding the safe daily limit of 400 mg/day and may cause jitteriness, insomnia, and elevated heart rate.
Check the caffeine content of your green tea extract product and account for it in total daily caffeine intake.
View details →Green tea extract tends to lower stored vitamin E in the liver, independent of changes in fat content.
Grüntee-Extrakt kann die Vitamin-E-Konzentration in der Leber leicht senken. Bei gleichzeitiger Einnahme beider Supplemente empfiehlt sich die Einhaltung der empfohlenen Vitamin-E-Tagesdosis (12–15 mg/Tag).
View details →Green tea extract supplementation combined with other nutrients increases peak plasma concentrations of bioactive compounds in rats.
Glutamin kann die Bioverfügbarkeit von Grüntee-Extrakt-Inhaltsstoffen erhöhen. Gesamt-EGCG-Menge aus allen Quellen unter 800mg/Tag halten (EFSA 2018).
View details →Scientific Sources
- Source
- Source
- Population nutrikinetics of green tea extract (2018)
- Green tea catechins prevent low-density lipoprotein oxidation via their accumula (2016)
- Therapeutic Role of Green Tea Polyphenols in Improving Fertility: A Review (2018)
- Biotransformation of catechin and extraction of active polysaccharide from green (2015)
- A green tea-containing starch confection increases plasma catechins without prot (2016)
- Source
- Green tea extract protects leptin-deficient, spontaneously obese mice from hepat (2008)
- Antioxidant effects of green tea polyphenols on free radical initiated peroxidat (2002)
- Green tea extract as food antioxidant. Synergism and antagonism with α-tocophero (2012)
- Studies on the effects of oral administration of nutrient mixture, quercetin and (2010)
- Prospective randomized trial evaluating blood and prostate tissue concentrations (2020)
- Antidepressive-like effects and antioxidant activity of green tea and GABA green (2016)
- NIH Dietary Supplement Label Database (DSLD)
Frequently Asked Questions
What is Green Tea Extract used for?
Green tea extract contains EGCG (C22H18O11) as primary bioactive antioxidant catechin.
What is the recommended dosage for Green Tea Extract?
400 mg. Any time. Can take on empty stomach.
Does Green Tea Extract interact with other supplements?
Green Tea Extract has 15 verified interactions. Top: Catechin, Vitamin B9 (Folate).
When is the best time to take Green Tea Extract?
Any time. Can take on empty stomach.
Is Green Tea Extract safe to combine with other supplements?
Always check interactions before combining supplements. Use VitalStack to verify your full stack for free.
Check how Green Tea Extract fits your full stack
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Check Your Stack →Not medical advice. VitalStack is not a medical device. For personalized health recommendations, consult a healthcare provider.