Effectiveness of Green Tea in a Randomized Human Cohort: Relevance to Diabetes and Its Complications

ANDI Centre of Excellence for Biomedical and Biomaterials Research and Department of Biosciences University of Mauritius, Réduit, Mauritius.
BioMed research international 09/2013; 2013(4):412379. DOI: 10.1155/2013/412379
Source: PubMed


Epidemiological studies have argued that green tea could mitigate diabetes and its complications. This study investigated the phytophenolic profile of Mauritian green tea and its antioxidant propensity. The effect of green tea on the risk factors: waist-hip ratio, glucose level, arterial pressure, antioxidant status, and alanine aminotransferase (ALT) in prediabetics was assessed. The experimental group consumed 3 cups of green tea daily for 14 weeks followed by a 2-week washout period. The control group followed a water regimen. Green tea contained high level of phenolics related to its antioxidant power. Green tea suppressed waist-hip ratio of women from a significant increase and suppressed mean arterial pressure of men and women from a significant decrease after week 14. It reduced ALT level in women by 13.0% (P < 0.1) while increasing the antioxidant potential of men and women sera by 2.7% (P < 0.1) and 5.1% (P < 0.1). The study timescale may have been too short to enable demonstration of effects on fasting plasma glucose and HbA1c outcomes. Green tea regimen could form part of a healthy lifestyle that might ameliorate features of metabolic syndrome and subsequent risks for diabetes and its complications. This trial is registered with NCT01248143.

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Available from: Theeshan Bahorun, May 13, 2014
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    • "Green tea extract (GTE) has been extensively studied as herbal remedy due to antioxidation [1] [2], antihypertension [3], antimutagenicity [4], anticarcinogenesis [5] and enhancing glucose tolerance [6] effects to protect against cardiovascular diseases [7], ultraviolet attack [8], oral diseases [9] and obesity [10]. These effects are mainly attributed to the multiple target properties of GTE in signaling and regulatory pathways. "
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    • "Catechins are abundant in less-fermented teas (Henning et al. 2003; Murakami et al. 2006; Myers et al. 2013). It is believed that most of the health benefits, including antioxidant, anti-inflammatory, antiproliferative, antimutagenic, antibacterial and antiviral properties as well as protection against cardiovascular disease, hyperglycaemia , metabolic disorders and some cancers (Dufresne & Farnworth 2001; Gupta et al. 2002; Luczaj & Skrzydlewska 2005; Cabrera et al. 2006; Anandh Babu et al. 2008; Kuriyama 2008; Venables et al. 2008; Butt & Sultan 2009; Meltzer et al. 2009; Schramm 2013; Toolsee et al. 2013; Uchiyama et al. 2013) are due to EGCG. Tea may also reduce the risk of osteoporotic fractures among elderly people (Shen et al. 2013). "
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