The effects of epigallocatechin-3-gallate on thermogenesis and fat oxidation in obese men: a pilot study.
OBJECTIVE
The development of obesity is characterized by an increase in adipose tissue mass and by concomitant and profound changes in almost all organ functions leading to diseases such as hypertension, diabetes mellitus and coronary heart disease. Recent data from human studies indicate that the consumption of green tea and green tea extracts may help reduce body weight, mainly body fat, by increasing postprandial thermogenesis and fat oxidation. However, human studies investigating the metabolic effects of the most predominant tea catechin, EGCG, alone are absent.


METHODS
In a randomized double blind, placebo-controlled, cross-over pilot study, six overweight men were given 300 mg EGCG/d for 2d. Fasting and postprandial changes in energy expenditure (EE) and substrate oxidation were assessed.


RESULTS
Resting EE did not differ significantly between EGCG and placebo treatments, although during the first postprandial monitoring phase, respiratory quotient (RQ) values were significantly lower with EGCG compared to the placebo.


CONCLUSIONS
These findings suggest that EGCG alone has the potential to increase fat oxidation in men and may thereby contribute to the anti-obesity effects of green tea. However, more studies with a greater sample size and a broader range of age and BMI are needed to define the optimum dose.
Boschmann
Michael
M
Universitary Medicine Berlin, Charité Campus Buch, Franz-Volhard-Center for Clinical Research, D-13125, Berlin, Germany. michael.boschmann@charite.de
Thielecke
Frank
F
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D001481:Basal Metabolism / Q000187:drug effects / Q000502:physiology; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D008297:Male; D009765:Obesity / Q000188:drug therapy* / Q000378:metabolism; D010084:Oxidation-Reduction; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D010865:Pilot Projects; D010936:Plant Extracts / Q000494:pharmacology; D013662:Tea / Q000737:chemistry*; D022722:Thermogenesis / Q000187:drug effects* / Q000502:physiology; D015431:Weight Loss
D000975:Antioxidants; D010936:Plant Extracts; D013662:Tea; D002392:Catechin; C045651:epigallocatechin gallate