Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans
Abdul G Dulloo, Claudette Duret, Dorothée Rohrer, Lucien Girardier, Nouri Mensi, Marc Fathi, Philippe Chantre and Jacques Vandermander
1 From the Department of Physiology, Faculty of Medicine, University of Geneva; Geneva University Hospital; and Laboratoires Arkopharma, Nice, France.
2 Supported in part by Arkopharma Laboratories and by the Swiss National Science Research Fund.
3 Address reprint requests to AG Dulloo, Institute of Physiology, University of Fribourg, Rue de Musée 5, CH-1700 Fribourg, Switzerland. E-mail: abdul.dulloo@.unifr.ch.
ABSTRACT
Background: Current interest in the role of functional foods in weight control has focused on plant ingredients capable of interfering with the sympathoadrenal system.
Objective: We investigated whether a green tea extract, by virtue of its high content of caffeine and catechin polyphenols, could increase 24-h energy expenditure (EE) and fat oxidation in humans.
Design: Twenty-four–hour EE, the respiratory quotient (RQ), and the urinary excretion of nitrogen and catecholamines were measured in a respiratory chamber in 10 healthy men. On 3 separate occasions, subjects were randomly assigned among 3 treatments: green tea extract (50 mg caffeine and 90 mg epigallocatechin gallate), caffeine (50 mg), and placebo, which they ingested at breakfast, lunch, and dinner. |
