LONDON, United Kingdom
A meta study of 40 research papers linking black tea and disease prevention suggests taking three cups a day can slash the risk of a heart attack by 60 percent and dramatically reduce the threat of diabetes.
Researchers Dr. Carrie Ruxton and Pamela Mason published their work in the December issue of UK Nutrition Bulletin. They estimate people taking three to six cups of tea a day lower their risk of contracting heart disease by 30 to 57 percent compared to those who drink little or no tea.
They report, "These beneficial findings are thought to be due to a variety of positive factors in black tea, such as antioxidant flavonoids and theanine, which help to control blood pressure, regulate nitric oxide production (which impacts on arterial function) and inhibit platelet aggregation (which can cause blood clots).”
"Our review also found evidence of a link between black tea consumption and a reduced risk of Type 2 diabetes when one to five cups of tea were consumed daily, depending on the study under investigation," says Ruxton BSc, PhD, Senior Lecturer at the University of Westminster.
She says the amount required to produce such benefits should be the subject of further research, but “three to six cups of black tea daily appears to contribute to cardiovascular health.”
Tea drinkers are known to reduce the amount of LDL (bad cholesterol), reduce clotting and manage high blood pressure. Tea helps maintain the production of nitric oxide essential to the health of arteries, as well as inhibiting platelet aggregation, a main cause of blood clots.
Source: UK Nutrition Bulletin
Citatation: Ruxton, C. H. S. and Mason, P. (2011), Is black tea consumption associated with a lower risk of cardiovascular disease and type 2 diabetes?. Nutrition Bulletin. doi: 10.1111/j.1467-3010.2011.01937.x