Cited by 146Tea Polyphenols and EffectsNatural Antidiabetic Agents StudiesCoffee research and impacts

Effects of green tea catechins with or without caffeine on glycemic control in adults: a meta-analysis of randomized controlled trials

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Zheng, Xin-Xin, Xu, Yan-Lu, Li, Shao-Hua, Hui, Rutai, Wu, Yong-Jian, Huang, Xiao-Hong·2013·The American Journal of Clinical Nutrition

Abstract

Background The effect of green tea catechins (GTCs) with or without caffeine on glycemic control is controversial.Objective We aimed to identify and quantify the effects of GTCs or GTC-caffeine mixtures on glucose metabolism in adults.Design A comprehensive literature search was conducted to identify relevant trials of GTCs with or without caffeine on markers of glycemic control [fasting blood glucose (FBG), fasting blood insulin (FBI), glycated hemoglobin (Hb A1c), and homeostatic model assessment of insulin resistance (HOMA-IR)]. Weighted mean differences were calculated for net changes by using fixed-effects models. Prespecified subgroup analyses were performed to explore the influence of covariates on net changes in FBG and FBI concentrations.Results Twenty-two eligible randomized controlled trials with 1584 subjects were identified. Pooled analyses showed that FBG (-1.48 mg/dL; 95% CI: -2.57, -0.40 mg/dL) decreased significantly with GTCs with or without caffeine, whereas FBI (0.04 μU/mL; 95% CI: -0.36, 0.45 μU/mL), Hb A1c (-0.04%; 95% CI: -0.15, 0.08%), and HOMA-IR (-0.05; 95% CI: -0.37, 0.26) did not. Subgroup analyses indicated that the glucose-lowering effect was apparent when the duration of follow-up was over a median of 12 wk. Overall, no significant heterogeneity was detected for FBG, FBI, Hb A1c, or HOMA-IR.Conclusions The meta-analysis showed that the administration of GTCs with or without caffeine resulted in a significant reduction in FBG. The limited data available on GTCs did not support a positive effect on FBI, Hb A1c, or HOMA-IR. Thus, more large and well-designed trials are needed in the future. This trial was registered at http://www.crd.york.ac.uk/prospero as CRD42012002139.

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  • Others have found cardiometabolic improvement effects of anthocyanin, catechin, curcumin, flavanol, genistein, and quercetin.

    “Others have also found cardiometabolic improvement effects of anthocyanin,32 catechin,33,34 curcumin,35 flavanol,36 genistein,37 and quercetin.38,39”

    From Micronutrient Supplementation to Reduce Cardiovascular Risk (2022) · cites this paper as [33]

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  1. Hase T, Komine Y, Meguro S, Takeda Y, Takahashi H, Matsui Y, Inaoka S, Katsuragi Y, Tokimitsu I, Shimasaki H, et al. Antiobesity effects of tea catechins in humans. J Oleo Sci 2001;50:599-605.
  2. Mirzaei K, Hossein-Nezhad A, Karimi M, Hosseinzadeh-Attar MJ, Jafari N, Najmafshar A, Larijani B. Effect of green tea extract on bone turnover markers in type 2 diabetic patients; a double-blind, placebo- controlled clinical trial study. Daru 2009;17:38-44.
  3. Tsuchida T, Itakura H, Nakamura H. Reduction of body fat in humans by long-term ingestion of catechins. Prog Med 2002;22:2189-203.
  4. Higgins JPT, Green S, eds. Cochrane handbook for systematic reviews of interventions. Version 5.0.2. New York, NY: Wiley, 2009.
  5. Mohammadi S, Hosseinzadeh Attar MJ, Karimi M, Hosseinnezhad A, Eshraghian MR, Hosseini SH, Rahmani M, Karimi F, Jafari N. The effects of green tea extract on serum adiponectin concentration and insulin resistance in patients with type 2 diabetes mellitus. J Zanjan University of Medical Sciences and Health Services 2010;18:44-57.
  6. Kozuma K, Chikama A, Hishino E, Kataoka K, Mori K, Hase T, Katsuragi Y, Tokimitsu I, Nakamura H. Effect of intake of a beverage containing 540mg catechins on the body composition of obese women and men. Prog Med 2005;25:1945-57.

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Authors
Zheng, X.-X., Xu, Y.-L., Li, S.-H., Hui, R., Wu, Y.-J., & Huang, X.-H.
Affiliations
Chinese Academy of Medical Sciences & Peking Union Medical College (CN)
Venue
The American Journal of Clinical Nutrition
Publisher
Elsevier BV
Published
2013-04
Volume
97
Issue
4
Pages
750-762
ISSN
0002-9165 (ISSN-L)
OpenAlex
W2137040425
Cited by
146
References
69
Citations by year
2026: 7 · 2025: 3 · 2024: 11 · 2023: 7 · 2022: 11 · 2021: 10 · 2020: 21 · 2019: 13 · 2018: 11 · 2017: 15 · 2016: 13 · 2015: 7 · 2014: 9 · 2013: 8
FWCI
1.81
Type
journal article
Language
en
Open access
Locations
  • American Journal of Clinical Nutrition (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Pathology and Forensic Medicine › Tea Polyphenols and Effects
  • Health Sciences › Medicine › Endocrinology, Diabetes and Metabolism › Natural Antidiabetic Agents Studies
  • Health Sciences › Medicine › Pharmacology › Coffee research and impacts
Keywords
green tea catechins, caffeine, glycemic control, fasting blood glucose, fasting insulin, HbA1c, insulin resistance, glucose metabolism, type 2 diabetes
MeSH terms
Adult, Blood Glucose, Caffeine, Catechin, Glycated Hemoglobin, Humans, Hyperglycemia, Hypoglycemic Agents, Insulin, Insulin Resistance, Phytotherapy, Metabolic Diseases, Plant Extracts, Camellia sinensis

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