No support shown for the use of pycnogenol for chronic disorders

February 15, 2012 By Milly Dawson

The manufacturer of a dietary supplement made from French pine bark, Pycnogenol, markets it widely for the prevention or treatment of many chronic disorders, ranging from asthma to erectile dysfunction, but a recent systematic review found no sound basis for the claims.

“We found that no solid evidence exists to support health claims that are being made for the antioxidant supplement Pycnogenol,” said senior author Jimmy Volmink, M.D., Ph.D., Dean of the Faculty of Health Sciences at Stellenbosch University in South Africa and director of the SA Cochrane Centre, Medical Research Council of South Africa. “Only 15 randomized controlled trials…have evaluated the effects of Pycnogenol.” The manufacturer sponsored 11 of them.

Pycnogenol is derived from the bark of pine trees that grow only in southern France. It contains the antioxidant proanthocyanidin, which is present in fruits, red wine and chocolate.

Dietary supplements represent a multibillion industry, notes Volmink. “Steps are currently being taken in several countries to improve the regulation of the industry, in terms of quality, safety and the validity of health claims.” Meanwhile, consumers must interpret claims cautiously, he said.

The fifteen trials - performed in the USA, Europe, China and Iran - involved 791 participants. The disorders studied included , attention deficit hyperactivity disorder, chronic venous insufficiency, diabetes, erectile dysfunction, hypertension and osteoarthritis. Two trials were done with children; the rest with adults.

The new review's authors could draw no solid conclusions regarding benefits that many studies purported to find. The 15 trials exhibited poor quality, with small sample sizes (11 to 156 participants) and often inadequate blinding. Key results were sometimes missing for relevant outcomes and some trials provided results only for the treatment group taking Pycnogenol®, but not for controls.

Roberta W. Scherer, Ph.D., an associate scientist at the Johns Hopkins Bloomberg School of Public Health said, “A majority of the studies were funded by the manufacturer, leading to increased risk of bias.” She noted that because the trials had small samples, it is difficult to have confidence in the findings. The trials also examined diverse outcomes, making combining the results difficult or impossible. “Also, safety is hard to assess with small trials,” she said. “It’s not really shown” in small, short-term trials like those done on Pycnogenol.

Both scientists called for bigger, better studies of Pycnogenol before consumers can trust in its efficacy and safety.

Explore further: For a less biased study, try randomization

More information: Schoonees A., Visser J., Musekiwa A., Volmink J. (2012). Pycnogenol® for the treatment of chronic disorders. The Cochrane Library, Issue 2.

Related Stories

For a less biased study, try randomization

April 13, 2011

A new review of existing research confirms that the so-called “gold standard” of medical research — the randomized controlled study — provides a safeguard against bias.

Recommended for you

Researchers identify source of opioids' side effects

January 17, 2017

A commercially available drug may help drastically reduce two side effects of opioid painkillers—a growing tolerance and a paradoxical increased sensitivity to pain—without affecting the drugs' ability to reduce pain, ...

CVS generic competitor to EpiPen, sold at a 6th the price

January 12, 2017

CVS is now selling a rival, generic version of Mylan's EpiPen at about a sixth of its price, just months after the maker of the life-saving allergy treatment was eviscerated before Congress because of its soaring cost to ...

Many misuse OTC sleep aids: survey

December 29, 2016

(HealthDay)—People struggling with insomnia often turn to non-prescription sleep remedies that may be habit-forming and are only intended for short-term use, according to a new Consumer Reports survey.

The pill won't kill your sexual desire, researchers say

December 15, 2016

Taking the pill doesn't lower your sexual desire, contrary to popular belief, according to research published in the Journal of Sexual Medicine. The authors of the research, from the University of Kentucky and Indiana University ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.