Tea leaves may foretell health benefits

From Rea Blakey
CNN Medical Unit

WASHINGTON (CNN) -- Aside from water, it's the most widely consumed beverage in the world. And some researchers say there's growing evidence that tea, plain old black tea, packs positive health benefits.

Others dispute that.

"We do not find that tea is protective for clinical heart disease," said Dr. Meir Stampfer of the Harvard School of Public Health.

Some recent studies seem to show that tea drinking slows the progression of coronary artery disease, and reduces the risk of stroke and some cancers. But no studies have shown exactly how tea seems to work inside the body, until now.

The research, paid for by the North American Tea Trade Health Research Association, followed 50 patients with heart disease.

Four cups a day

Participants were asked to drink four cups of black tea each day for a month, along with water.

"What we found was after drinking tea, blood vessel function improved significantly," said Dr. Joseph Vita of Boston University Medical Center in Massachusetts.

Despite his research conclusion, Vita warns, tea is not a substitute for medications.

Previous studies have shown that people who eat diets high in flavonoids -- which can be found in foods such as grapes, apples, onions and black tea -- have a lower risk of heart attack and stroke.

Cardiologists say much more research needs to be conducted to brew up a direct correlation between tea consumption and reducing coronary risks.

"The main limitation of the study is it measured what happened in the arm artery of patients. This is quite a long distance and many steps away from actual clinical heart disease," Stampfer said.

In the meantime, experts say there are five known lifestyle changes that can help prevent heart disease. They include:

•  Quitting smoking

•  Avoiding obesity by keeping your body mass index below 25

•  Engaging in regular rigorous exercise most days of the week

•  Consuming only moderate amounts of alcohol

•  Maintaining a low-fat diet high in fruits and vegetables.