A study released January 23, 2012 showed that drinking three cups of black tea per day lowers your blood pressure by 2-3 points. This study is a major find and could help prevent the number of health diseases like high blood pressure and the risk of heart disease.
Researcher Jonathan M. Hodgson, PhD, of the School of Medicine and Pharmacology at the University of Western Australia in Perth, Australia, and colleagues in the Archives of Internal Medicine say, “At a population level, the observed differences in BP (blood pressure) would be associated with a 10% reduction in the prevalence of hypertension and a 7% to 10% reduction in the risk of heart disease and stroke.”
Researchers in Australia studied 95 men and women who were regular tea drinkers, ages 35 to 75 years old, and had daytime systolic blood pressure (SBP) between 115 and 150 mm Hg. One group was given three cups of black tea per day to drink for six months, while the other half of the group was given a placebo which was colored and flavored to look and taste like black tea. The placebo even had caffeine content to help control the study findings. Also, neither group was allowed to drink any other kind of tea during their study duration.
By the end of the six months, those who drank the black tea showed a reduction in their blood pressure. So why does drinking black tea lower a person’s blood pressure? Researchers believe it’s because of the effects on endothelial functions.
Endothelial dysfunction may be an early marker for changes in a person’s blood pressure. Drinking black tea can help improve endothelial function. In previous studies done by Jonathan Hodgson, PhD from University of Western Australia in Perth showed that flavonoids in tea affect the nitric oxide status and will lower the level of endothelin.
Researchers said in a statement, “This could contribute to reduced vascular tone and lower blood pressure. A recent meta-analysis suggests that green tea and its flavonoids, many of which are structurally similar to black tea flavonoids, together with caffeine can reduce body weight and abdominal fatness.”
DailyRX explains why this study of drinking black tea will reduce blood pressure is an important finding for the United States:
It is estimated that close to 30% of the United States population has high blood pressure (hypertension), or about 90 million people. Blood pressure is measured as the force the pumping blood exerts on the walls of the arteries in the body.
When this pressure is higher than normal (120/80 mmHg), patients are at risk for heart attack, stroke, congestive heart failure, kidney failure, and aneurysms in the arteries and brain. Even moderate high blood pressure can lead to a shortened life expectancy. Most high blood pressure is asymptomatic, and is discovered during a routine checkup.
As blood pressure reaches dangerously high levels, some people may experience symptoms such as headache, ringing in the ears, visual changes, and irregular heartbeat. These symptoms are a medical emergency. At particularly high risk for high blood pressure are African Americans, people who are obese, smokers, diabetics, having high salt intake, and having a family history. Alcohol abuse and cocaine use can also cause hypertension.
Diagnosis is made by measuring blood pressure over several doctors visits, and is treated by lifestyle modification first, such as smoking cessation, weight loss, dietary changes, and exercise. There are hundreds of different medications to treat hypertension, such as beta-blockers (Lopressor, Inderal), diuretics (Diamox, HydroDiuril), Calcium channel blockers (Norvasc, Procardia), and ACE inhibitors (Lotensin, Vasotec, Capoten).