Consumption of black and green tea has no effect on inflammation, haemostasis and endothelial markers in smoking healthy individuals
Obejective: Firstly, to study the effect of tea and tea polyphenols on cardiovascular risk indicators of the inflammatory system (IL6, IL1β and TNF-α, CRP), and on haemostasis and endothelial proteins with an acute phase behaviour (fibrinogen, vWF, PAI-1, FVIIa and u-PA). Secondly, to study the relationship between plasma levels of antioxidants (α-tocopherol, β-carotene and vitamin C) and these acute-phase, cardiovascular risk indicators.Design: Randomized study.Subjects: Sixty-four smoking healthy volunteers were recruited by newspaper advertisements; there were five dropouts.Intervention: Four-week administration of black tea, green tea, green tea polyphenol isolate and mineral water (13–16 per group).Measures: Plasma levels of the inflammatory markers IL6, IL1β, TNF-α, CRP, fibrinogen, vWF, PAI-1, FVIIa and u-PA and of the antioxidants α-tocopherol, β-carotene and vitamin C.Results: Different dosages of tea polyphenols had no effect on inflammation, haemostasis and endothelial markers. There was a significant negative correlation between the levels of the antioxidant β-carotene and the inflammation markers IL6 and fibrinogen (r=−0.35 and r=−0.37, respectively, P<0.01) in this group of smokers. Remarkably, there was a significant positive correlation between the levels of the antioxidant α-tocopherol and the inflammation marker IL6 (r=0.28, P<0.05).Conclusions: Tea drinking had no effect on the levels of the inflammation, haemostasis and endothelial cardiovascular risk factors measured. We did observe a relationship between the antioxidant variables α-tocopherol and β-carotene and inflammation markers in this group of healthy smoking subjects.Sponsorship: This work was supported in part by Unilever Research, Vlaardingen, The Netherlands. European Journal Of Clinical Nutrition (2000) 24, 757–763