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Pine Bark Extract; Pycnogenol is investigated for its general health and anti-diabetic properties and its ability to enhance Nitric Oxide, which may have a significant benefit for those with erectile dysfunction. Recent studies have also shown that supplementation may help to limit symptoms associated with chronic inflammation in autoimmune disease.

Our evidence-based analysis on pycnogenol features 103 unique references to scientific papers.

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Summary of Pycnogenol

Primary information, health benefits, side effects, usage, and other important details

Pycnogenol is a patented formulation of Pine Bark Extract which is standardized to 65-75% Procyanidin compounds by weight. Procyanidins are chain-like structures consisted of catechins similar to some found in green tea (the green tea catechins that do not have 'gallate' in their names). Pycnogenol is similar to grape seed extract and cocoa polyphenols as those are the three most common sources of Procyanidins.

Pycnogenol's benefits include increased blood flow (via a mechanism related to increased nitric oxide levels) and improved blood glucose control. The former exerts cardioprotective effects and may help with erectile dysfunction, while the latter appears to be anti-diabetic.

There are many human trials conducted on Pycnogenol, but a good deal of them have industry funding. Although industry funding doesn't necessarily invalidate published results, it should always be noted. Although the range of Pycnogenol research has significant breadth, it also has a relative lack of study replication. Some of the studies of Pycnogenol in autoimmune disease are also open-label, meaning that neither the researchers nor the subjects are blinded to treatments. While promising, these results need to be interpreted with a degree of caution since this type of experimental design fails to control for placebo effects or any unconscious bias that may be harbored by researchers analyzing the data. The one topic that appears to have been replicated numerous times is the effects on erectile dysfunction, with the caveat that all of the studies are confounded with the inclusion of l-arginine. So the effects of Pycnogenol alone on erectile dysfunction are still unknown.

Pycnogenol does appear to possess dual anti-oxidant and anti-inflammatory properties, with the latter being confirmed in humans and possibly being subject to a build-up effect over time. The low-dose buildup effect of Pycnogenol as an anti-inflammatory agent would make it useful in a multinutrient format, but it may not be the most potent anti-inflammatory in isolation. The degree of measured anti-inflammatory potential on COX enzymes (targets of Aspirin) are still lower than Aspirin itself.

Although not the most potent anti-inflammatory agent out there, Pycnogenol has shown some efficacy in alleviating symptoms in patients with autoimmune disease. Although the type of rampant inflammation during a flare far-exceeds the ability of pycnogenol, it has shown some efficacy for patients in remission phases of their disease, where symptoms tend to be driven by lower-level, chronic inflammation. One preliminary study has shown that pycnogenol may be particularly effective for relieving dry eye/ mouth symptoms associated with Sjorgren’s syndrome, a common autoimmune condition in women.

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How to Take

Recommended dosage, active amounts, other details

Although doses in the range of 40-60mg have been noted to be effective over a prolonged period of time, standard doses of Pycnogenol appear to be in the range of 100-200 mg per day.

Studies have used twice daily dosing (dividing the daily total into two even doses to be taken with breakfast and dinner) as well as once daily dosing with breakfast. Both dosing strategies appear to be effective although they haven't been directly compared. It can be asborbed equally well when taken with or without food.

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Human Effect Matrix

Unlocked for Examine members

The Human Effect Matrix summarizes human studies to tell you what effects Pycnogenol has on your body, how much evidence there is, and how strong these effects are.

Full details are available to Examine members.
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
grade-b Notable Very High See all 3 studies
An improvement in nitric oxide dependent blood flow appears to occur following procyanidin supplementation which has been noted in both unhealthy persons as well as healthy controls; there does not appear to be a per se hypotensive effect either.
grade-b Minor High See all 4 studies
Pycnogenol has shown mixed effects on blood pressure in hypertensive subjects. While the majority of trials examined reported modest blood-pressure lowering effects, one randomized controlled trial found no effect on blood pressure. The mixed results suggest that pycnogenol blood-pressure lowering effects may be dependent on the underlying cause of hypertension. More research is needed to determine which individuals with hypertension may benefit from supplementation.
grade-c Notable Very High See 2 studies
Appears to reduce leg swelling secondary to the enhancement of blood flow. While the evidence is not overly robust, it is comparable if not better than the reference supplement of Horse Chestnut
grade-c Notable Very High See 2 studies
The preliminary evidence at this point in time (promising and independent, but limited) support the usage of pycnogenol in reducing all symptoms of osteoarthritis, reaching up to a halving of symptoms but requiring 90 days for effects to occur
grade-c Minor Very High See 2 studies
A slight reduction in asthmatic symptoms has been noted with Pycnogenol supplementation
grade-c Minor - See study
An improvement in attention has been noted, possibly secondary to improvements in general cognition, in students during prolonged academic testing
grade-c Minor - See study
An improvement in cognitive function has been noted in students during academic testing
grade-c Minor Very High See 2 studies
A reduction in general oxidation is noted following prolonged Pycnogenol supplementation
grade-c Minor Very High See all 3 studies
May reduce LDL cholesterol for as long as pycnogenol is taken (some evidence to suggest a normalization after supplement cessation)
grade-c Minor - See study
A reduction in pain secondary to improvements in symptoms of osteoarthritis has been noted, and while notable in this certain instance it is not certain if there are inherenet analgesic effects
grade-c Minor - See study
An improvement in skin elasticity has been noted with Pycnogenol supplementation
grade-c Minor - See study
Oral supplementation of standard doses of procyanidins can improve skin quality in elderly women, other demographics not tested
grade-c Minor - See study
An increase in well being and mood has been noted in students undergoing academic testing, which correlated with improved test scores
grade-c Minor - See study
A decrease in some symptoms of menopause has been noted with Pycnogenol supplementation
grade-c - - See 2 studies
grade-c - - See study
No significant alterations in C-Reactive protein noted
grade-c - - See 2 studies
grade-c - - See 2 studies
grade-c - - See study
No significant alterations in heart rate noted
grade-c - Very High See 2 studies
No significant influence on standard inflammatory cytokines
grade-c - - See study
Despite one study establishing the blood flow effects are dependent on nitric oxide, there do not appear to be any significant differences in nitric oxide quantities in saliva
grade-d Notable Very High See 2 studies
Reduces symptoms of chronic venous insufficiency. Potentially useful as an adjunct to compression therapy.
grade-d Minor - See study
May be proerectile in persons with organic erectile dysfunction (due to poor blood flow)
grade-d Minor Moderate See 2 studies
May increase HDL cholesterol, but has mixed evidence to support it and may be unreliable
grade-d Minor - See study
One open-label study (lacks blinding for investigators or subjects and no placebo-control) indicated that pynogenol efficacy for IBS symptoms was on par with some of the common pharmacological antispasmodic agents. Although the study design was weak, other studies demonstrating that pycnogenol has a relaxing effect on intestinal smooth muscle tissue lends some increased confidence that it may also be effective as a treatment for IBS.
grade-d Minor - See study
A decrease in nF-kB activity has been confirmed in humans given 200mg pycnogenol daily for five days, to the degree of around 15%
grade-d Minor Moderate See 2 studies
Possible cholesterol lowering effects of small magnitude, but these are not wholly reliable
grade-d - - See study
grade-d - - See study
grade-d - - See study
No significant alterations on triglycerides

Studies Excluded from Consideration

  • Confounded with other components as a 'anti-oxidant' supplement[1]

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Things to Note

Primary Function:

Also Known As

Pine Bark Extract, Pine Bark Procyanidins, Procyanidins

Do Not Confuse With

Grape Seed Extract (same molecules, different source)

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Click here to see all 103 references.