The effects of catechin rich teas and caffeine on energy expenditure and fat oxidation: a meta-analysis

Obes Rev. 2011 Jul;12(7):e573-81. doi: 10.1111/j.1467-789X.2011.00862.x. Epub 2011 Mar 2.

Abstract

Different outcomes of the effect of catechin-caffeine mixtures and caffeine-only supplementation on energy expenditure and fat oxidation have been reported in short-term studies. Therefore, a meta-analysis was conducted to elucidate whether catechin-caffeine mixtures and caffeine-only supplementation indeed increase thermogenesis and fat oxidation. First, English-language studies measuring daily energy expenditure and fat oxidation by means of respiration chambers after catechin-caffeine mixtures and caffeine-only supplementation were identified through PubMed. Six articles encompassing a total of 18 different conditions fitted the inclusion criteria. Second, results were aggregated using random/mixed-effects models and expressed in terms of the mean difference in 24 h energy expenditure and fat oxidation between the treatment and placebo conditions. Finally, the influence of moderators such as BMI and dosage on the results was examined as well. The catechin-caffeine mixtures and caffeine-only supplementation increased energy expenditure significantly over 24 h (428.0 kJ (4.7%); P < 0.001 and 429.1 kJ (4.8%); P < 0.001, respectively). However, 24 h fat oxidation was only increased by catechin-caffeine mixtures (12.2 g (16.0%); P < 0.02 and 9.5 g (12.4%); P = 0.11, respectively). A dose-response effect on 24 h energy expenditure and fat oxidation occurred with a mean increase of 0.53 kJ mg(-1) (P < 0.01) and 0.02 g mg(-1) (P < 0.05) for catechin-caffeine mixtures and 0.44 kJ mg(-1) (P < 0.001) and 0.01 g mg(-1) (P < 0.05) for caffeine-only. In conclusion, catechin-caffeine mixtures or a caffeine-only supplementation stimulates daily energy expenditure dose-dependently by 0.4-0.5 kJ mg(-1) administered. Compared with placebo, daily fat-oxidation was only significantly increased after catechin-caffeine mixtures ingestion.

Publication types

  • Meta-Analysis
  • Review

MeSH terms

  • Adipose Tissue / metabolism*
  • Body Mass Index
  • Caffeine / pharmacology*
  • Catechin / pharmacology*
  • Dietary Supplements
  • Dose-Response Relationship, Drug
  • Energy Metabolism / drug effects*
  • Humans
  • Oxidation-Reduction
  • Plant Extracts / pharmacology*
  • Tea / chemistry*
  • Thermogenesis / drug effects

Substances

  • Plant Extracts
  • Tea
  • Caffeine
  • Catechin