News / Health

Popular Supplement Fails to Lower Blood Pressure

New tests dispute prior findings of studies on pine bark extract

Multimedia

Audio
Art Chimes

Previous research has shown an array of benefits from taking pine bark extract, but a new study questions that.
Previous research has shown an array of benefits from taking pine bark extract, but a new study questions that.

A new study of a popular dietary supplement indicates that, while pine bark extract is safe, it has no significant effect on blood pressure or other risk factors for heart disease. This new research seems to contradict evidence from earlier studies.

Previous research has shown an array of benefits from taking pine bark extract, ranging from reducing inflammation to treating skin disorders and menstrual symptoms. It is reported to have antioxidant properties and to help lower blood pressure, as well.



To test out some of the claims, Stanford University researcher Randall Stafford and colleagues recruited people who were overweight and had blood pressure slightly higher than normal — in other words, people likely to try a dietary supplement rather than expensive prescription drugs.

People in the study were randomly assigned to either take pine bark extract or a look-alike placebo.

After 12 weeks, the researchers found essentially no benefit from the supplement.

"We in fact found no difference between the pine bark extract group and the placebo group," said Stafford. "There were very small changes in blood pressure. And in fact, there was a slightly greater reduction in blood pressure among the placebo group, but it was a change that could have easily been explained by random chance."

Stafford says the results were surprising, because previous studies had shown some cardiovascular benefit. But he noted that there were problems with the methodology in the earlier studies, which were not placebo-controlled, double-blind trials like his was.

Also, products sold as "pine bark extract" can be made in a variety of ways and are not all the same, since these sorts of nutritional supplements are only loosely regulated, at least here in the U.S.

"There are a number of different pine bark extracts out on the market. They are extracted or derived in different ways. It is possible that other pine bark might have benefits where this one doesn't," he said.

In the United States and many other countries, government officials don't require natural dietary supplements to be proven safe and effective, the way other drugs are.

Stafford says his study illustrates how flimsy the scientific basis is for claims made by sellers of and advocates for many different supplements.

"Much of the expenditure on dietary supplements are for products that really don't have rigorous data supporting their use."

The study by Stanford researcher Randall Stafford and colleagues is published in the American Medical Association journal, Archives of Internal Medicine.

You May Like

Multimedia Social Media Documenting, Not Driving, Hong Kong Protests

Unlike in Arab Spring uprisings, pro-democracy protesters in Hong Kong aren't relying on Twitter and Facebook to organize, but social media still plays a role More

Analysis: Occupy Central Not Exactly Hong Kong’s Tiananmen

VOA's former Hong Kong, Beijing correspondent compares and contrasts 1989 Tiananmen Square protest with what is now happening in Hong Kong More

Bambari Hospital a Lone Place of Help in Violence-Plagued CAR

Only establishment still functioning in CAR's second city is main hospital More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
The Legacy of Jimmy Carter: The Preacher from Plainsi
X
October 01, 2014 10:45 AM
It is common in the United States to see tourists flock to sites associated with America's presidents. Some are privately owned and others are run by the National Park Service or the National Archives -- but most have helped draw business and people into the towns and cities where they are located. As VOA’s Kane Farabaugh reports, there is one particular presidential hometown that is unique in what it has to offer those who make the trip.
Video

Video The Legacy of Jimmy Carter: The Preacher from Plains

It is common in the United States to see tourists flock to sites associated with America's presidents. Some are privately owned and others are run by the National Park Service or the National Archives -- but most have helped draw business and people into the towns and cities where they are located. As VOA’s Kane Farabaugh reports, there is one particular presidential hometown that is unique in what it has to offer those who make the trip.
Video

Video Hong Kong Protests Draw New Supporters on National Holiday

On the 65th anniversary of the founding of Communist China, Hong Kong protesters are hoping to stage the largest pro-democracy demonstration since the 1989 Tiananmen protests. VOA's Brian Padden visited one of the protest sites mid-day, when the atmosphere was calm and where the supporters were enthusiastic about joining what they are calling the umbrella revolution.
Video

Video India's PM Continues First US Visit

India's prime minister is on his first visit to Washington, to strengthen political and economic ties between the world's oldest and the world biggest democracies. He came to the U.S. capital from New York, the first stop on his five-day visit to the country that denied him an entry visa in the past. From Washington, Zlatica Hoke reports Modi seemed most focused on attracting foreign investment and trade to increase job opportunities for his people.
Video

Video Malaysia Struggles to Stop People Joining Jihad

Malaysian authorities say militant groups like the so-called "Islamic State" have used social media to entice at least three dozen Malaysian Muslims to fight in what they call "jihad" in Syria and Iraq. As Mahi Ramkrishnan reports from Kuala Lumpur, counterterrorism police are deeply worried about what could happen when these militants return home.
Video

Video Could US Have Done More to Stop Rise of Islamic State?

President Obama says airstrikes against Islamic State militants in Syria will likely continue for some time because, in his words, "there is a cancer that has grown for too long." So what if President Obama had acted sooner in Syria to arm more-moderate opponents of both the Islamic State and the Syrian government? VOA State Department Correspondent Scott Stearns reports from the United Nations.
Video

Video Treasure Hunters Seek 'Hidden Treasure' in Central Kenya

Could a cave in a small village in central Kenya be the site of buried treasure? A rumor of riches, left behind by colonialists, has some residents dreaming of wealth, while others see it as a dangerous hoax. VOA's Gabe Joselow has the story.
Video

Video Ebola Patients Find No Treatment at Sierra Leone Holding Center

At a holding facility in Makeni, central Sierra Leone, dozens of sick people sit on the floor in an empty university building. They wait in filthy conditions. It's a 16-hour drive by ambulance to Kailahun Ebola treatment center. Adam Bailes was there and reports on what he says are some of the worst situations he has seen since the beginning of this Ebola outbreak. And he says it appears case numbers may already be far worse than authorities acknowledge.
Video

Video Identifying Bodies Found in Texas Border Region

Thousands of immigrants have died after crossing the border from Mexico into remote areas of the southwestern United States in recent years. Local officials in south Texas alone have found hundreds of unidentified bodies and buried them in mass graves in local cemeteries. Now an anthropologist and her students at Baylor University have been exhuming bodies and looking for clues to identify them. VOA’s Greg Flakus has more from Waco, Texas.
Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.Colonel Steve ‘Spiros’ Pisanos left Greece and came to the U.S. to learn to fly. He flew fighters for the Allies in World War II, narrowly escaping death multiple times.

AppleAndroid