Green Tea Extract (EGCG) for Metabolism Boost
EGCG increases fat oxidation during exercise and daily activity, with the strongest effects when combined with caffeine — a genuine metabolic optimizer at the margins.
Overview
How It Works
Dosing & Protocol
Typical dose
- Recommended dose
- 400–500 mg EGCG/day with caffeine, ideally 30–60 min pre-exercise.
- Expected timeframe
- 4-12 weeks
Protocol
- form
- Extract standardised for EGCG, or 3-5 cups of brewed green tea daily
- duration
- 8-12 weeks
- co factor
- Take with food, never fasted. Metabolism boost is the marketing phrase for a real but small effect: green tea catechins with caffeine increase 24-hour energy expenditure by roughly 3-4%, around 60-100 kcal/day, through COMT inhibition prolonging noradrenaline signalling. Set that against what actually determines metabolic rate - fat-free mass, which resistance training builds, and total activity including non-exercise movement, which dwarfs any supplement effect. Metabolic rate also falls with weight loss regardless of supplementation, and partial tolerance develops to the catechin-caffeine effect over weeks. This is worth about a 15-minute walk per day.
- titration
- Up to 500 mg/day of extract; never above 800 mg/day EGCG
- starting dose
- 300 mg/day of standardised extract with food
Evidence
What the studies say
Thermogenic ingredients and body weight regulation: a review of clinical evidence
Hursel R, Westerterp-Plantenga MS
Thermogenic ingredients produced increases in 24-hour energy expenditure of a few percent
Effects of green tea catechins with or without caffeine on energy expenditure and fat oxidation: a meta-analysis
Hursel R, Viechtbauer W, Dulloo AG +3 more
Catechin-caffeine mixtures raised 24-hour energy expenditure by roughly 4-5%
Safety
Caveats
Take with food to avoid rare liver issues; decaffeinated GTE loses much of the effect; tolerance develops to the thermogenic component.
Less likely to help if
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.