Tea flavonoids and cardiovascular disease.

Drinking tea could have a significant impact on public health. Health benefits are believed to be largely due to the presence of high levels of flavonoids. Tea is a rich source of flavonoids, and often the major dietary source. Tea intake and intake of flavonoids found in tea have been associated with reduced risk of cardiovascular disease in cross-sectional and prospective population studies. In addition, flavonoids have consistently been shown to inhibit the development of atherosclerosis in animal models. A variety of possible pathways and mechanisms have been investigated. The focus of this review is on the potential of tea and tea flavonoids to improve endothelial function, and reduce blood pressure, oxidative damage, blood cholesterol concentrations, inflammation and risk of thrombosis. There is now consistent data to suggest that tea and tea flavonoids can improve endothelial function. This may be at least partly responsible for any benefits on risk of cardiovascular disease. Additional studies are needed to investigate whether regular consumption of tea can reduce blood pressure, inflammation and the risk of thrombosis. The evidence for benefit on oxidative damage and cholesterol reduction remains weak.