The effect of black tea on risk factors of cardiovascular disease in a normal population

Abstract

Objectives: A prospective randomized controlled clinical trial determined the effect of Mauritian black tea consumption on fasting blood plasma levels of glucose, lipid profiles and antioxidant status in a normal population. Methods: The study group (71%) consumed 3 x 200. ml of black tea infusate/day for 12. weeks without additives followed by a 3. week wash-out. The control group (29%) consumed equivalent volume of hot water for same intervention period. Results: The tea used had high levels of gallic acid derivatives (50 ± 0.4. mg/L), flavan-3-ols (42 ± 2. mg/L), flavonols (32 ± 1. mg/L) and theaflavins (90 ± 1. mg/L). Daily 9. g supplementation of black tea infusate induced, in a normal population, a highly significant decrease of fasting serum glucose (18.4%; p < 0.001) and triglyceride levels (35.8%; p < 0.01), a significant decrease in LDL/HDL plasma cholesterol ratio (16.6%; p < 0.05) and a non significant increase in HDL plasma cholesterol levels (20.3%), while a highly significant rise in plasma antioxidant propensity (FRAP: 418%; p < 0.001) was noted Conclusion: Black tea consumed within a normal diet contributes to a decrease of independent cardiovascular risk factors and improves the overall antioxidant status in humans. © 2011 Elsevier Inc..