Green Tea Supplementation, Fat Oxidation and Body Composition in Overweight Individuals

NCT04628624 | Completed

• 1 other identifier: FST/FREP/17/703
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to investigate the effects of green tea extract (GTE) on fat oxidation, body composition and exercise performance in overweight individuals. The study will be conducted under laboratory conditions following an 8 week supplemental period. Participants will be required to attend the laboratory for a pre-screening/familiarisation trial followed by assessments at week 0 (baseline), week 2, 4 and 8. Across the intervention, participants will maintain habitual dietary intake and follow a prescribed exercise programme. Additionally participants will be randomised to either a placebo, green tea extract or GTE with antioxidant supplementation. It is hypothesised that the addition of antioxidants with GTE will enhance fat oxidation in overweight individuals more than GTE or placebo. It is further hypothesised that such improvements in fat oxidation due to GTE will lead to improvements in both body composition variables and submaximal exercise performance (metabolic efficiency) in overweight, but otherwise healthy persons.

Conditions

Overweight and Obesity; Fat Burn

Keywords

Green Tea; Exercise Metabolism

Outcome Measures

Primary Outcomes (4)

• Fat oxidation (max)

  Assessment of maximal fat oxidation rate (via expired air) during incremental exercise

  Change from Baseline maximal fat oxidation at 1 month

• Fat oxidation (max)

  Assessment of maximal fat oxidation rate (via expired air) during incremental exercise

  Change from Baseline maximal fat oxidation at 2 months

• Fat oxidation (min)

  Assessment of exercise intensity at which point fat oxidation is negligable

  Change from Baseline minimum fat oxidation at 1 month

• Fat oxidation (min)

  Assessment of exercise intensity at which point fat oxidation is negligable

  Change from Baseline minimum fat oxidation at 2 months

Secondary Outcomes (30)

• Height

  Change from baseline height at 1 month

• Height

  Change from baseline height at 2 months

• Weight

  Change from baseline weight at 1 month

• Weight

  Change from baseline weight at 2 months

• Bodyfat percentage

  Change from baseline bodyfat percentage at 1 month

Study Arms (3)

Placebo group

PLACEBO COMPARATOR

Placebo - capsulated, colour matched potato starch (\~450mg per capsule) - provided by Biocare Ltd., UK using standard 00 vegetable capsules (hydroxypropyl methylcellulose). Dosage: 2 divided doses (1 capsule mid morning, 1 capsule mid afternoon) - daily for 8 weeks.

Dietary Supplement: Placebo control

Green tea 1

EXPERIMENTAL

Capsulated decaffeinated green tea extract (dGTE) (standardised to 70% EGCG concentration, 571mg total per day, containing 400mg EGCG - provided by Biocare Ltd., UK using standard 00 vegetable capsules (hydroxypropyl methylcellulose). Dosage: 2 divided doses (1 capsule mid morning, 1 capsule mid afternoon) - daily for 8 weeks.

Dietary Supplement: GTE 1

Green tea 2

EXPERIMENTAL

Capsulated decaffeinated green tea extract (dGTE) (standardised to 70% EGCG concentration, 571mg total per day, containing 400mg EGCG + 150mg quercitin and 150mg alpha lipoic acid - provided by Biocare Ltd., UK using standard 00 vegetable capsules (hydroxypropyl methylcellulose). Dosage: 2 divided doses (1 capsule mid morning, 1 capsule mid afternoon) - daily for 8 weeks.

Dietary Supplement: GTE 2

Interventions

Placebo control DIETARY_SUPPLEMENT

8 week supplementation period, with participants consuming 2 capsules per day containing potato starch

Also known as: Placebo

Placebo group

GTE 1 DIETARY_SUPPLEMENT

8 week supplementation period, with participants consuming 2 capsules per day containing green tea extract (571mg/d)

Also known as: Decaffeinated green tea extract

Green tea 1

GTE 2 DIETARY_SUPPLEMENT

8 week supplementation period, with participants consuming 2 capsules per day containing green tea extract with additional antioxidants (150mg of quercitin and 150mg of alpha lipoic acid)

Also known as: Decaffeinated green tea extract and antioxidants

Green tea 2

Eligibility Criteria

• Age: 18 Years - 55 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Men and women, UK based, above 18 years of age
• Below 45 years of age (for men) and below 55 years of age (for women)
• Baseline maximal oxygen uptake \>25ml/kg/min and \<45ml/kg/min representative of normal (but not high) fitness levels; and a body mass index (BMI) \>25kg/m2 and \<33kg/m2
• All participants: No known history (including family history) of heart abnormalities, hypertension, coronary heart disease or diabetes (determined from pre-study health screen questionnaire)
• All participants: No known history of liver related disorders (e.g. hepatitis, Wilsons disease, cirrhosis).
• All participants: Not currently suffering from any musculo-skeletal injury, or any other reason that may prevent participation in cardiovascular exercise
• All participants: Have not suffered from recent viral infections ie: influenza (defined within the prior 2 months)
• All participants: Not suffering from any known blood related disorders, including blood coagulation abnormalities, or have any adverse reactions to blood taking
• All participants: Not taking any prescribed or over-the-counter medication which may influence exercise training (with the exception of inhalers for exercise induced asthma or contraceptive pill)
• All participants: Not consuming or prepared to refrain from consumption, any commercial supplementation which conflicts with the study parameters ie: creatine, other green tea or weight loss products.

You may not qualify if:

• Anyone below the age of 18 years, or above 45 years (for men) and 55 years (for women) - based on exercise testing guidelines by the American College of Sports Medicine (ACSM).
• Those who do not meet the criteria for baseline maximal oxygen uptake or BMI assessment
• All participants: anyone with a known history (including family history) of heart abnormalities, hypertension, coronary heart disease or diabetes (determined from pre-study health screen questionnaire)
• All participants: anyone with a known previous history of liver related disorders.
• All participants: Anyone suffering from a current musculo-skeletal injury, or any other reason that may prevent participation in cardiovascular exercise
• All participants: those suffering from recent viral infections ie: influenza (defined within the prior 2 months)
• All participants: Those with known blood related disorders, including blood coagulation abnormalities, or have any adverse reactions to blood taking. This includes any participant who has or potentially has an infectious disease, inc. HIV, and all types of hepatitis.
• All participants: Anyone taking any prescribed or over-the-counter medication which may influence exercise training (with the exception of inhalers for exercise induced asthma or contraceptive pill)
• All participants: Anyone consuming or not prepared to refrain from consumption, any commercial supplementation which conflicts with the study parameters ie: creatine, other green tea or weight loss products.
• FEMALE ONLY: Any participant who is, suspects they may be or becomes pregnant during the study.

Sponsors & Collaborators

• Anglia Ruskin University: lead

Study Sites (1)

Anglia Ruskin University

Cambridge, CB1 1PT, United Kingdom

Location

Related Publications (13)

• Roberts JD, Roberts MG, Tarpey MD, Weekes JC, Thomas CH. The effect of a decaffeinated green tea extract formula on fat oxidation, body composition and exercise performance. J Int Soc Sports Nutr. 2015 Jan 21;12(1):1. doi: 10.1186/s12970-014-0062-7. eCollection 2015.

  PMID: 25650043 BACKGROUND

• Hursel R, Viechtbauer W, Westerterp-Plantenga MS. The effects of green tea on weight loss and weight maintenance: a meta-analysis. Int J Obes (Lond). 2009 Sep;33(9):956-61. doi: 10.1038/ijo.2009.135. Epub 2009 Jul 14.

  PMID: 19597519 BACKGROUND

• Hursel R, Westerterp-Plantenga MS. Thermogenic ingredients and body weight regulation. Int J Obes (Lond). 2010 Apr;34(4):659-69. doi: 10.1038/ijo.2009.299. Epub 2010 Feb 9.

  PMID: 20142827 BACKGROUND

• Ichinose T, Nomura S, Someya Y, Akimoto S, Tachiyashiki K, Imaizumi K. Effect of endurance training supplemented with green tea extract on substrate metabolism during exercise in humans. Scand J Med Sci Sports. 2011 Aug;21(4):598-605. doi: 10.1111/j.1600-0838.2009.01077.x. Epub 2010 Mar 10.

  PMID: 20459475 BACKGROUND

• Venables MC, Hulston CJ, Cox HR, Jeukendrup AE. Green tea extract ingestion, fat oxidation, and glucose tolerance in healthy humans. Am J Clin Nutr. 2008 Mar;87(3):778-84. doi: 10.1093/ajcn/87.3.778.

  PMID: 18326618 BACKGROUND

• Dulloo AG, Duret C, Rohrer D, Girardier L, Mensi N, Fathi M, Chantre P, Vandermander J. 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 Dec;70(6):1040-5. doi: 10.1093/ajcn/70.6.1040.

  PMID: 10584049 BACKGROUND

• Ryu OH, Lee J, Lee KW, Kim HY, Seo JA, Kim SG, Kim NH, Baik SH, Choi DS, Choi KM. Effects of green tea consumption on inflammation, insulin resistance and pulse wave velocity in type 2 diabetes patients. Diabetes Res Clin Pract. 2006 Mar;71(3):356-8. doi: 10.1016/j.diabres.2005.08.001. Epub 2005 Sep 19.

  PMID: 16169629 BACKGROUND

• Maki KC, Reeves MS, Farmer M, Yasunaga K, Matsuo N, Katsuragi Y, Komikado M, Tokimitsu I, Wilder D, Jones F, Blumberg JB, Cartwright Y. Green tea catechin consumption enhances exercise-induced abdominal fat loss in overweight and obese adults. J Nutr. 2009 Feb;139(2):264-70. doi: 10.3945/jn.108.098293. Epub 2008 Dec 11.

  PMID: 19074207 BACKGROUND

• Feng WY. Metabolism of green tea catechins: an overview. Curr Drug Metab. 2006 Oct;7(7):755-809. doi: 10.2174/138920006778520552.

  PMID: 17073579 BACKGROUND

• Hodgson AB, Randell RK, Jeukendrup AE. The effect of green tea extract on fat oxidation at rest and during exercise: evidence of efficacy and proposed mechanisms. Adv Nutr. 2013 Mar 1;4(2):129-40. doi: 10.3945/an.112.003269.

  PMID: 23493529 BACKGROUND

• Dean S, Braakhuis A, Paton C. The effects of EGCG on fat oxidation and endurance performance in male cyclists. Int J Sport Nutr Exerc Metab. 2009 Dec;19(6):624-44. doi: 10.1123/ijsnem.19.6.624.

  PMID: 20175431 BACKGROUND

• Eichenberger P, Colombani PC, Mettler S. Effects of 3-week consumption of green tea extracts on whole-body metabolism during cycling exercise in endurance-trained men. Int J Vitam Nutr Res. 2009 Jan;79(1):24-33. doi: 10.1024/0300-9831.79.1.24.

  PMID: 19839000 BACKGROUND

• Achten J, Jeukendrup AE. Maximal fat oxidation during exercise in trained men. Int J Sports Med. 2003 Nov;24(8):603-8. doi: 10.1055/s-2003-43265.

  PMID: 14598198 BACKGROUND

MeSH Terms

Conditions

Overweight; Obesity

Interventions

Antioxidants

Condition Hierarchy (Ancestors)

Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Biological Factors; Molecular Mechanisms of Pharmacological Action; Pharmacologic Actions; Chemical Actions and Uses; Protective Agents; Physiological Effects of Drugs; Specialty Uses of Chemicals

Study Officials

• Justin Roberts, PhD

  Anglia Ruskin University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Masking Details: Nutritional supplements will be provided in a randomised, double-blinded manner. Both the participants and research testers will be masked from knowing the specifics of the supplement intervention.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Model Details: Participants randomly assigned to either placebo, green tea extract (GTE) or GTE with antioxidants in a parallel, double blind manner

Study Record Dates

• First Submitted: November 5, 2020
• First Posted: November 13, 2020
• Study Start: December 1, 2018
• Primary Completion: December 1, 2019
• Study Completion: March 1, 2020
• Last Updated: November 13, 2020

Record last verified: 2020-11

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)