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Green Tea Extract

herbs

Green tea extract is a concentrated source of polyphenols, particularly catechins and EGCG, derived from unoxidised tea leaves. It provides the bioactive compounds of green tea in a convenient supplement form with standardised levels of beneficial constituents.

Benefits

Antioxidant support
Metabolic function
Cognitive performance
Cardiovascular health
Thermogenesis

Dosage

Typical Dose

300–400 mg daily

Upper Limit

800 mg daily

Timing

With meals to enhance absorption and reduce gastric irritation

Forms & Bioavailability

Standardised extract (EGCG)

High absorption when standardised to 50–98% polyphenols; EGCG content directly affects potency

Powder

Moderate absorption; variable polyphenol content depending on processing

Capsules

Good absorption; convenient dosing with consistent active compound levels

Side Effects

Nausea or gastric upset on an empty stomach
Dizziness or headaches at high doses
Sleep disruption due to caffeine content
Liver toxicity with excessive prolonged use

Interactions

Iron absorption may be reduced; separate dosing by 2+ hours
May potentiate effects of anticoagulants and antiplatelet medications
Caffeine-related interactions with stimulants
May reduce efficacy of certain chemotherapy agents

Research Summary

Numerous studies demonstrate green tea extract's antioxidant and anti-inflammatory properties, with consistent evidence supporting benefits for weight management and metabolic health. Research indicates EGCG supports cardiovascular function and may enhance cognitive performance, though effects are often modest. Long-term safety studies are generally favourable, though concentrated extracts warrant cautious use due to potential hepatotoxicity at extreme doses.

Where to Buy Green Tea Extract

We recommend buying from reputable retailers. Check reviews and third-party testing.

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Disclaimer: This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement, especially if you have existing health conditions or take medication.