In new human trial, supplements of the flavonoids quercetin and a green tea component, epicatechin were studied to see if they improved endothelial function.

The cells lining blood vessels are called endothelial. The cells lining blood vessels normally lose flexibility as we age. It was the objective of one research study to learn if a green tea component would improve endothelial function in 12 healthy men. Each member of the quercetin group was given 200 mg of quercetin, epicatechin, epigallocatechin gallate or a placebo. Nitric Oxide was used to determine if the flavonoids were having a beneficial effect on endothelium. Endothelium used the nitric oxide to signal surrounding muscle to relax, and so it dilated the blood vessels. Researchers also measured levels of endothelin-1 (ET 1). Edothelin-1 acts to constrict blood vessels. Read the rest of this entry »