Effect of Green Tea Flavonoid Supplementation on Features of Metabolic Syndrome (MeS)

Abstract

Green tea, rich in flavonoids, has been shown to possess cardiovascular health benefits. This is a preliminary report on a randomized controlled trial investigating whether green tea beverage or extract supplementation improved the cardiovascular risk profile associated with MeS. Age and sex‐matched trios of participants with MeS were randomly assigned to control (4 cups water/day), green tea beverage (4 cups/day), or green tea supplement (2 capsules & 4 cups water/day) group for 8 weeks. Fasting blood samples, physical measurements were taken at screening, 4 & 8 weeks. Blood samples were analyzed for lipid, glucose, catechin and nitric oxide (NOx) levels. Body weight decreased in green tea (‐1.9 Kg) vs control (+0.1 Kg). There is an increasing trend in HDL cholesterol in green tea (+1.0 mg/dl) vs control. A decrease in ox‐LDL was found in green tea group vs baseline. Interestingly, no consistent effects were seen on glucose levels. No significant difference in the plasma catechin and serum NOx concentrations among the three groups. However, green tea beverage group showed a decreasing trend in serum NOx levels (p<0.1) compared to baseline, indicating anti‐ inflammatory effect. Green tea beverage or supplements may aid weight loss, raise HDL levels and may help in reducing ox‐LDL and NOx levels in MeS subjects. Thus, chronic green tea consumption may promote cardiovascular health by reducing oxidative stress and inflammation in at risk subjects.Funded by CHES, OSU