Effectiveness of green tea in a randomized human cohort: relevance to diabetes and its complications

Naushad Ali Toolsee, Okezie I Aruoma, Teeluck K Gunness, Sudhir Kowlessur, Venkatesh Dambala, Fatima Murad, Kreshna Googoolye, Diana Daus, Joseph Indelicato, Philippe Rondeau, Emmanuel Bourdon, Theeshan Bahorun, Naushad Ali Toolsee, Okezie I Aruoma, Teeluck K Gunness, Sudhir Kowlessur, Venkatesh Dambala, Fatima Murad, Kreshna Googoolye, Diana Daus, Joseph Indelicato, Philippe Rondeau, Emmanuel Bourdon, Theeshan Bahorun

Abstract

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 ClinicalTrials.gov NCT01248143.

Figures

Figure 1
Figure 1
Flow diagram showing trial profile and study design.
Figure 2
Figure 2
Daily mean calorie index variation for participants under green tea and water regimen during the 14-week intervention period and 2-week washout period in a male and female Mauritian population. Main and error bars represent mean values and standard deviations, respectively, for experimental group (male, n = 33; female, n = 32) and control group (male, n = 30; female, n = 28).
Figure 3
Figure 3
Daily lipid/fat ratio for participants under green tea and water regimen during the 14-week intervention period and 2-week washout period in a male and female Mauritian population. Main and error bars represent mean values and standard deviations, respectively, for experimental group (male, n = 33; female, n = 32) and control group (male, n = 30; female, n = 28).
Figure 4
Figure 4
The prophylactic effect of green tea extracts against free radical which might be a causative agent of metabolic syndrome. Main and error bars represent mean value and standard deviation of three independent experiments, respectively. Statistical analyses were performed, using independent samples t-test, for multiple comparisons. ***Time taken for 50% hemolysis to occur was significantly different from that of control (P < 0.01).

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Source: PubMed

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