A Little Review of Green Tea Extract intake on Fat Oxidation

¹Daniel Zapata-Gomez

 ¹ Laboratory of Exercise Science, MEDS Clinic, Santiago, CHILE

Time intake of green tea in the β- oxidation effects.

Tea is a very popular beverage in whole South America, as well as coffee and matte. His origins have been from China and it is manufactured from the leaf and bud of the plant Camellia sinensis, species of the Theaceae family, contains naturally occurring flavonoids and caffeine. This plant can be manufactured using different process determining the type of tea (i.e. fermented, semi-fermented and “non fermented”; case of the green tea) [1, 2]. Therefore the green tea has a high concentration of catechin polyphenol existing four types of catechin. The epigallocatechin-3-gallate (EGCG) is considerer as the active component and the most abundant in the green tea [2]. Nevertheless the Green tea composition is complex having a range of component (Table 1) [2]. Regardless of the variety of component, several authors agree with the active component are the poliphenoles and the caffeine. However, 250 ml of Green tea contain ~ 300 mg of total catechins and ~ 90 mg of caffeine [2].

Currently, several studies have investigated the effects of green tea extract (GTE) showing an increase of the β-oxidation but, not in all of the studies was observed a positive result, understanding that, this effect depend on a range of factors as: dose, concentration of catechin as well as caffeine, chronic or acute intake, and experimental group.

Seems to be that the EGCG works synergistically with a mount of caffeine and no for alone way in the β-oxidation function. Randell et al. [3] investigated the duration variable of decaffeinated GTE (dGTE) effect on exercise metabolism. In a cross-over, placebo controlled, 2 dose of encapsulate dGTE (EGCG 634 + 3 mg/d + 1136 + 24 mg/d + ~ 11 mg/d). The participants ingested 2 dose 2 hrs before to 30 min cycle exercise bout (50% Wmax) in a period of 28 days, the subjects was controlled on 1d, 7d and 28d. The authors observed that no effect on whole body fat oxidation rates or fat metabolism- related blood metabolites during exercise in physically active healthy males. Otherwise is important to considerer the “caffeine concentration” because the caffeine may works synergistically with the catechins increasing the β-oxidation only using small doses (<600 ml/dl) [2]. Furthermore this effect (e.g. no responder vs responder) has relation directly with the levels of consume of caffeine/day, founding a high effect in no-consume caffeine people [4, 5, 6]. The period of green tea adaptation and time ingestion has been studied for several authors (ref), but is still poor the consensus founding result over 24hrs, 7d and 10 weeks [2, 7,8]. Hodgson et al. [2] proposed a definition of GTE intake duration in relation with the adaptive effect (i.e. 24h as acute effect; 10 week as chronic effect). Dulloo et al. [9] investigated the energy expenditure (EE) and fat oxidation after 24h of green tea vs caffeine intake. 10 Healthy men intaked a) 2 GTE capsule 3 times in a period of 24 h (i.e. breakfast, lunch and dinner) every GTE capsule contain 50mg of caffeine and 90mg of ofepigallocatechin-gallate, b) 50mg caffeine or c) placebo. They showed a 4% increased in the EE and increase of the 31% + 3,1 % (Placebo), 33,8 + 2,4 % (Caffeine) and 41, 5 + 3,1 % (Green tea) fat oxidation. This could conclude the possible acute effect of 24h green tea intake in the fat oxidation rate, eventhough this result is more significant when GTE is used than when using caffeine, because the dose of caffeine need to be high (> 100 mg). The acute effect in the increase fat oxidation using GTE could be determined for the “catechins plasma concentration”, this peak concentration to be after 2 hours after intake. Hodgson et al. [10] show the acute effect of the GTE in 24 h and 7 days after intake. 39 healthy physical active male participants were randomly allocated in 3 groups to intake 7 days of GTE, 6 days of Placebo and 1 day of GTE and 7 days of Placebo. They have shown that the maximal “EGCG plasmatic concentration” is obtained at 120 min after the intake and this conclusion could be linked with an improvement of “fat oxidation”. In relation of that, Hodgson et al. [11] Have shown metabolic response to GTE during rest and moderate-intensity exercise after 120, 140, 150, 160 and 180 min. Twenty-seven healthy participant were recruit to this study, they were randomly allocated into two group (e.g. GTE group vs Placebo group) after 120 min rest of GTE/Placebo intake both group performed 60 min by cycle using 50% watts máx previously calculated. In effect, they have shown that increases lipolysis at 120 min after intake. In this study they no analyzed the fat oxidation nevertheless exist an associate between the lipolysis rate and the β-oxidation and exercise. The evidences raises in this manuscript have shown the green tea effect as well the increase in the beta-oxidation when is combined with endurance exercise using 50-60% of cardiovascular capacity. Otherwise, recently the studies have shown the result about the HIT, this interval training improve the beta-oxidation, cardiovascular capacity and another healthy benefits.

To improve the beta-oxidation using Green Tea, probably could be usefully in combine whit some intensity cardiovascular training protocol.

Bibliography

1.     Navamayooran Thavanesan. “The putative effects of green tea on body fat: an evaluation of the evidence and a review of the potential mechanisms”. British Journal of Nutrition (2011), 106, 1297–1309.

2.     Adrian B. Hodgson, Rebecca K. Randell, and Asker E. Jeukendrup. “The Effect of Green Tea Extract on Fat Oxidation at Rest and during Exercise: Evidence of Efficacy and Proposed Mechanisms”. American Society for Nutrition. Adv. Nutr. 4: 129–140, 2013.

3.     Rebecca K. Randell, Adrian B. Hodgson, Silvina B. Lotito, Doris M. Jacobs, Matthew, Rowson, David J. Mela, and Asker E. Jeukendrup. “Variable Duration of Decaffeinated Green Tea Extract Ingestion on Exercise Metabolism”. Medicine & Science in Sports & Exercise, Publish Ahead of Print, Oct. 2013.

4.     Bell DG1, McLellan TM. “Effect of repeated caffeine ingestion on repeated exhaustive exercise endurance”. Med Sci Sports Exerc. 2003 Aug;35(8):1348-54.

5.     Ganio MS1, Klau JF, Casa DJ, Armstrong LE, Maresh CM. “Effect of caffeine on sport-specific endurance performance: a systematic review”. J Strength Cond Res. 2009 Jan;23(1):315-24.

6.     Holway FE1, Spriet LL. “Sport-specific nutrition: practical strategies for team sports”. J Sports Sci. 2011;29 Suppl 1:S115-25.

7.     Dullo AG, Duret C, Rohrer D, Girardier I, Mensi N, Fathi M, Chantre P, Vandermander J. “Efficacy of green tea extract rich in catechin polyphenols and caffeine in increase 24-h energy expenditure and fat oxidation in humans”. Am J Clin Nutr. 1999;70:1040-5.

8.     Rebecca K. Randell, Adrian B. Hodgson, Silvina B. Lotito, Doris M. Jacobs, Niels Boon, David J. Mela & Asker Jeukendrup. “No Effect of 1 or 7 d of Green Tea Extract Ingestion on Fat Oxidation during Exercise”. Med. Sci. Sports Exerc., Vol. 45, No. 5, pp. 883–891, 2013

9.     Abdul G Dulloo, Claudette Duret, Dorothée Rohrer, Lucien Girardier, Nouri Mensi, Marc Fathi, Philippe Chantre, and Jacques Vandermander. “Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans”. Am J Clin Nutr 1999;70:1040–5

10.  Adrian B. Hodgson, Rebecca K. Randell, Krishna Mahabir-Jagessar-T, Silvina Lotito, Theo Mulder, David J. Mela, Asker E. Jeukendrup, and Doris M. Jacobs. “Acute Effects of Green Tea Extract Intake on Exogenous and Endogenous Metabolites in Human Plasma”. J. Agric. Food Chem. 2014, 62, 1198−1208.

11.  Adrian B. Hodgson, Rebecca K. Randell, Niels Boon, Ursula Garczarek, David J. Mela, Asker E. Jeukendrup, Doris M. Jacobs. “Metabolic response to green tea extract during rest and moderate-intensity exercise”. Journal of Nutritional Biochemistry 24 (2013) 325–334.