The effects of green tea ingestion over four weeks on atherosclerotic markers

Abstract

Background: The objective of this study was to evaluate the effects of green tea ingestion over four weeks on atherosclerotic biological markers. Methods: After a one-week baseline period, 12 healthy male volunteers aged 28-42 years drank 600 mL of green tea daily for four weeks. Lipid profile, oxidized low-density lipoprotein (ox-LDL), total antioxidant capacity (TAC), C-reactive protein (CRP) and soluble cell adhesion molecules were measured at baseline and after two and four weeks ingestion of green tea. Results: There was no significant change in the concentrations of lipid profile, TAC, CRP, soluble intercellular adhesion molecule-1 (sICAM-1), or soluble E-selectin after ingestion of green tea. The levels of ox-LDL and soluble vascular cell adhesion molecule-1 (sVCAM-1) were significantly decreased after four weeks of green tea ingestion (Wilcoxon signed rank test, P = 0.006). Conclusions: The results of this study suggest an in vivo anti-oxidative effect for green tea and an influence of green tea on atherosclerotic biological markers. The effect of green tea seen on ox-LDL and sVCAM-1 provides a potential mechanism for the cardiovascular benefits of regular ingestion of green tea. © 2005 The Association of Clinical Biochemists.