Black tea consumption has been associated with maintaining healthy arteries in people with a history of heart disease say the authors of a study published by the American Heart Association. They found that black tea promotes activity of the endothelium, or inner lining of the blood vessels. A healthy endothelium allows blood vessels to expand or contract in response to minute-by-minute changes in the need for blood flow. It inhibits the formation of blood clots and the development of inflammation in the vessel wall, all of which are often impaired in people with atherosclerosis. In this study, researchers compared the immediate and longer-term effects of black tea to water consumption on the arteries of 50 people with coronary artery disease, and found that only the tea improved arterial function. Senior author Dr. Joseph Vita says these findings suggest that black tea may help reverse arterial dysfunction and could reduce the risk of heart attacks.
The theaflavins in black tea show antioxidant properties in model laboratory studies. In a recent Polish study, the frequency of pancreatic cancer declined in relation to an increasing lifetime consumption of black tea. Other research has yielded similar results when studying the effect of black tea on cancer incidence.
A Dutch study of men aged 65 to 84 concluded that increasing intake of foods containing flavonoids - 61% from black tea, 13% from onions, and 10% from apples - was strongly linked to a lower rate of death from stroke and other coronary disease.
Several leading laboratories around the world have shown that black tea extract is a powerful inhibitor of a variety of cancers in animal models. These include skin, lung, colon, esophagus and mammary gland cancers.
Dr. Kuang Yu Chen, professor of chemistry and chemical biology at Rutgers University and his team focused on TF-2 and two other major black tea polyphenol compounds to determine black tea's impact on cancer. The Rutgers paper, "Effects of Polyphenolic Compounds in Black Tea and Grape on the Expression of Specific Genes in Normal and Cancerous Human Cells" summarizes the team's work on polyphenols, compounds in tea and other foods with antioxidative and other biochemical properties.
Findings suggest that black tea consumption reverses endothelial dysfunction (constriction) in patients with coronary artery disease.
They suggest that their findings fit well with the growing appreciation that diet and lifestyle modifications are important approaches and treatment of atherosclerotic vascular disease.
