What Is Pycnogenol?

Medically Reviewed

The bark of various pine trees, extracts of which have been used for centuries as folk remedies for all kinds of ailments, are today sold as dietary supplements. One particular pine bark extract, called Pycnogenol, has been the focus of much research in recent years. It was apparently first extracted from a type of maritime pine (Pinus pinaster) in southwest France in the 1950s, and rights to it were subsequently acquired by a Swiss company, which patented the formula. Pycnogenol has become a best-selling supplement, marketed under countless brand names, with more than $500 million in annual sales worldwide.

Claims, purported benefits: Treats everything from attention deficit hyperactivity disorder (ADHD), diabetes, erectile dysfunction, hypertension, heart disease, and blood vessel disorders to menopausal symptoms, tinnitus, arthritis, colds, skin diseases, cognitive function, diabetes-related eye problems, and allergies.

What the science says: Pycnogenol’s manufacturer has supported hundreds of studies on it and publicized the positive findings. It’s not known how other pine extracts compare in terms of biochemical effects.

Many of the compounds in Pycnogenol (like other pine bark extracts) are flavonoids, which are common in plants and have been linked to a variety of potential health benefits. Its key flavonoids are called proanthocyanidins, and Pycnogenol is “standardized” to contain certain levels of a particular group of them (procyanidins). Various proanthocyanidins are also found in grapes, wine, cocoa, apples, tea, and some berries and nuts and may be responsible for some of their health benefits. Like many plant compounds, Pycnogenol is a powerful antioxidant. In addition, lab studies show it helps combat inflammation and has other potentially beneficial properties.

Most of the human studies on Pycnogenol have been done by a group of researchers in Italy or, in part, by employees of the manufacturer, which has often funded the research. The great majority of the published studies find at least some benefit from Pycnogenol. The problems: Most of the studies were small and short-term; many had methodological problems (such as the lack of a control group); and few were done by independent researchers.

Here’s a sampling of some of the more recent research.

Cardiovascular health. Some small early studies suggested that Pycnogenol reduces blood pressure or LDL (“bad”) cholesterol, but research since then has been inconsistent. In a 2013 study in Phytotherapy Research, obese people with metabolic syndrome undertook a diet and exercise program for six months; the half who took Pycnogenol experienced greater reductions in blood pressure, waist circumference, triglycerides, and blood sugar, and a larger increase in HDL (“good”) cholesterol. In contrast, a 2014 analysis of seven studies, in the Journal of Cardiovascular Pharmacology and Therapeutics, found no effect on cholesterol or triglycerides. One of the largest and most rigorous studies on pine bark extract (using a Japanese product, however, not Pycnogenol), published in the Archives of Internal Medicine in 2010, found no reduction in blood pressure or any other benefits in people at high risk for cardiovascular dis- ease who took the supplement for 12 weeks.

Chronic venous insufficiency. As noted in a 2014 review in Phytotherapy Research, a dozen placebo-controlled studies have suggested that Pycnogenol can help treat chronic venous insufficiency (which causes poor circulation in the legs, resulting in swelling, varicose veins, and possibly leg ulcers and clots).

Menopausal symptoms. Among several studies suggesting benefits, an eight-week Italian study in Panminerva Medica in 2011 found that Pycnogenol reduced hot flashes and other symptoms, compared to a placebo, as did an independent 12-week Japanese study in the Journal of Reproductive Medicine in 2013.

Cognitive health. An Australian study of older people in the Journal of Psychopharmacology in 2008 found that Pycnogenol improved some aspects of working memory compared to a placebo, but produced no changes in most other cognitive skills. Similarly, in an Italian study in the Journal of Neurosurgical Sciences in 2014, healthy middle-aged people who took the supplement showed more improvement in certain cognitive skills than a control group.

Hay fever. A small Canadian study in Phytotherapy Research in 2010 of people with birch pollen allergy found that Pycnogenol (started at least five weeks before the beginning of allergy season) reduced symptoms better than a placebo.

Asthma. Several studies found that Pycnogenol helps reduce symptoms and improve pulmonary function as an adjunct therapy in children and adults with mild to moderate asthma. • Erectile dysfunction (ED). A small 2003 Slovakian study in Nutrition Research found that Pycnogenol improved erectile function in men with ED compared to a placebo. Similar results were seen in two small studies that combined Pycnogenol with l-arginine (an amino acid often promoted for ED).

General reviews. A 2012 independent Cochrane review of 15 studies on Pycnogenol for the treatment of asthma, ADHD, chronic venous insufficiency, diabetes, erectile dysfunction, hypertension, and osteoarthritis concluded that, despite some positive findings from individual trials, the studies were too small, limited, and potentially biased to draw any conclusions about the efficacy and safety of the supplement.

Natural Medicines, a comprehensive database on research about complementary/alternative therapies, lists more than 30 conditions for which Pycnogenol is used. It concludes that the supplement is “possibly effective” (equal to a “C” rating) for hay fever, asthma, athletic per- formance, chronic venous insufficiency, and cognitive function, but that there is insufficient evidence to rate its effectiveness for any of the other conditions.

Common side effects: Pycnogenol appears to be safe. But since it may stimulate the immune system, people with autoimmune diseases, such as rheumatoid arthritis, should probably avoid it. Similarly, because it may, in theory at least, lower blood sugar too much and increase the risk of bleeding, people with diabetes or bleeding disorders should check with their doctors before trying Pycnogenol.

Our advice: More independent, well-designed studies on Pycnogenol are needed. Proper dosages are unknown (the studies have used varying doses), and long-term safety is uncertain. If you have any of the disorders for which Pycnogenol is promoted, you should be under professional care and shouldn’t simply prescribe Pycnogenol for yourself. The com- pounds in Pycnogenol may turn out to be beneficial for certain medical conditions, but for now no one really knows. Meanwhile, you can get these and other beneficial compounds from other plants in the form of healthful foods such as berries, grapes, and nuts.