Pycnogenol (Pine Bark)
Pinus pinaster extract
Pine-bark flavonoids for firmer, more hydrated skin
Evidence tier
Preliminary
Research weight
Citations
18 verified / 18
Classification
Joint & Skin
❝
What the evidence says. Early or small human trials; promising but not yet conclusive.
What is Pycnogenol (Pine Bark)?
Pycnogenol (Pine Bark) (Pinus pinaster extract) is a joint and skin supplement used for may improve elasticity & hydration. NutriDex grades the human evidence as Preliminary. Pycnogenol is a standardized, single-company branded extract of French maritime pine bark rich in procyanidin flavonoids that act as antioxidants. Small trials report modest improvements in skin elasticity and hydration alongside increased collagen-I and hyaluronic-acid-synthase gene expression. In melasma, an early single-arm trial and a later placebo-controlled RCT (alongside standard triple cream + sunscreen) reported reduced pigmentation, though in the controlled trial both arms improved. Evidence is limited by small samples, short durations, and frequent sponsorship by the extract's manufacturer.
Purported Benefits
✓May improve elasticity & hydration
✓Antioxidant support vs photodamage
✓May reduce melasma area & pigment
✓Linked to collagen/HA gene expression
Evidence by outcome
The same supplement can be well-proven for one use and unproven for another — here is the human evidence graded outcome by outcome.
| Outcome | Evidence | Effect | Studies |
|---|---|---|---|
| Improved skin elasticity & hydrationSmall RCT and manufacturer review show gains, but samples tiny and sponsor-linked. | Preliminary | ↑ benefit · small | 2 |
| Reduced melasma area & pigmentOpen trial positive, but the controlled RCT improved in both arms; not isolating effect. | Mixed | ↔ mixed · small | 2 |
| Chronic venous insufficiency symptomsMeta-analysis and registry studies reduce leg volume/symptoms; some are observational. | Moderate | ↑ benefit · moderate | 3 |
| Lower blood pressureSome meta-analyses show modest BP drops; a PRISMA meta-analysis found no effect. | Mixed | ↔ mixed · small | 3 |
| Lower fasting glucose & HbA1cTwo large RCT meta-analyses show small but consistent glycemic reductions. | Moderate | ↑ benefit · small | 2 |
| Improved endothelial functionOne crossover RCT in CAD improved flow-mediated dilation; small single trial. | Preliminary | ↑ benefit · moderate | 1 |
| Overall efficacy across chronic conditionsCochrane review of 27 RCTs rated all evidence very low-certainty; no firm conclusions. | Mixed | ↔ mixed | 1 |
Dosing & Compounds
Typical Dose
75–150 mg/day (oral, often split).
Active Compounds
Safety & Cautions
Well tolerated in short trials (occasional mild GI upset, dizziness, headache); long-term data limited. May have mild antiplatelet and blood-pressure-lowering effects — caution with anticoagulants, before surgery, and with antidiabetic drugs. Not established as safe in pregnancy/breastfeeding. Many trials are small and manufacturer-funded, so effects may be overstated. Educational only — always check with your doctor or pharmacist before combining Pycnogenol (Pine Bark) with any medicine.
Key Studies ★ 18 studies
meta-analysis
Alvares 2025 (systematic review & meta-analysis)
✓ PubMed
Meta-analysis of emerging CVI pharmacological treatments (5 studies) ranked Pycnogenol among the two most promising; it significantly improved skin resting flux (mean difference 21.04, 95% CI 9.29 to 32.80) and showed favorable but non-significant trends for pain and edema.
Systematic review
Weichmann & Rohdewald 2024
✓ Source
Review of 39 randomized, double-blind, placebo-controlled trials reports that Pycnogenol supplementation improved skin elasticity by 13% (vs 1% placebo) and reduced transepidermal water loss by 14% (vs 5% placebo) over 3 months in outdoor workers.
Meta-analysis
Frontiers Pharmacol NMA 2025
✓ Full text
Bayesian network meta-analysis of 19 trials (4,956 participants) ranked Pycnogenol highest for improving cognitive function in mild cognitive impairment (SUCRA 98.8%) and activities of daily living (SUCRA 100%).
Meta-analysis
Stanislavov / Frontiers Endocrinol 2023
✓ Full text
Meta-analysis of 3 RCTs (184 men) found L-arginine plus Pycnogenol significantly improved IIEF erectile function domain scores (mean difference 8.9 points, 95% CI 4.14 to 13.66, p=0.0002) versus placebo.
Meta-analysis
Mohammadi 2025
✓ PubMed
Meta-analysis of 27 RCTs (1685 participants): pine bark extract significantly reduced SBP (-2.26 mmHg), DBP (-2.62 mmHg), fasting blood glucose (-6.25 mg/dL), HbA1c (-0.32%), body weight (-1.37 kg), and LDL cholesterol (-5.07 mg/dL) vs control; no significant effect on BMI, waist circumference, insulin, HDL, triglycerides, or total cholesterol.
Systematic review
Robertson (Cochrane Review) 2020
✓ PubMed
Cochrane review of 27 RCTs (1641 participants) across 10 chronic disorders (asthma, ADHD, CVD, chronic venous insufficiency, diabetes, erectile/female sexual dysfunction, osteoarthritis, osteopenia, traumatic brain injury). All effects rated very low-certainty evidence; small samples, few trials per condition, and poor reporting mean no definitive conclusions on efficacy or safety of pine bark extract are possible.
Meta-analysis
Fogacci 2020
✓ PubMed
PRISMA-compliant meta-analysis of 7 randomized double-blind placebo-controlled trials (626 participants): pycnogenol showed NO significant effect on systolic BP (WMD -0.03 mmHg), diastolic BP (-0.14 mmHg), mean arterial pressure, or pulse pressure; results robust on leave-one-out sensitivity analysis.
meta-analysis
Hadi 2018 (systematic review & meta-analysis)
✓ PubMed
Pooled analysis of 9 trials (549 participants, 150-200 mg/day) found modest reductions in systolic (-3.22 mmHg, 95% CI -6.20 to -0.24) and diastolic blood pressure (-3.11 mmHg, 95% CI -4.60 to -1.62), with greater effect in hypertensives but not in well-designed trials.
meta-analysis
Hadi 2019 (systematic review & meta-analysis)
✓ PubMed
Meta-analysis of 14 trials (1,065 participants) found Pycnogenol significantly raised HDL-C (+3.27 mg/dL, 95% CI 0.19 to 6.36, p=0.038) but produced no clinically relevant change in total cholesterol, LDL-C, or triglycerides.
Systematic review & meta-analysis
Malekahmadi 2019 (systematic review & meta-analysis)
✓ PubMed
Meta-analysis of 24 RCTs (1,594 participants) found Pycnogenol significantly lowered fasting blood glucose (-5.86 mg/dl, 95% CI -9.56 to -2.15) and HbA1c (-0.29%, 95% CI -0.56 to -0.01), alongside reductions in systolic/diastolic BP, BMI, and LDL-C and a rise in HDL-C.
RCT
Lima 2021 (RCT)
✓ Source
Double-blind RCT (44 women), 75 mg twice daily for 60 days as adjunct to triple cream + sunscreen; mMASI and QoL improved — but both pycnogenol and placebo arms improved.
RCT
Marini 2012 (RCT)
✓ PubMed
12 weeks in 20 postmenopausal women improved skin elasticity and hydration (greatest in dry skin) with increased HAS-1 and collagen gene expression.
Randomized controlled trial
Enseleit 2012 (RCT, European Heart Journal)
✓ PubMed
Double-blind randomized placebo-controlled cross-over trial in 23 stable coronary artery disease patients found 200 mg/day for 8 weeks (on top of standard therapy) improved flow-mediated dilation from 5.3 to 7.0% (p<0.0001), with no improvement on placebo.
Open trial
Ni 2002 (open trial)
✓ PubMed
Single-arm 30-day trial in 30 women with melasma; mean melasma area fell 25.9 mm² and pigment intensity 0.47 unit (p<0.001).
Randomized controlled trial
Cisar 2008 (RCT)
✓ PubMed
Double-blind placebo-controlled trial in 100 knee osteoarthritis patients given 150 mg/day for 3 months significantly improved the WOMAC index and reduced VAS pain (p<0.04) while analgesic use fell in the treatment group but rose on placebo.
Randomized controlled trial
Steigerwalt 2009 (RCT)
✓ PubMed
Randomized controlled trial in 46 patients with early diabetic retinopathy (24 Pycnogenol vs 22 placebo) over 2-3 months significantly improved visual acuity (14/20 to 17/20), reduced retinal edema/thickness, and raised central retinal artery flow velocity (34 to 44 cm/s) versus negligible placebo change.
comparative study
Belcaro 2024 (registry/comparative study)
✓ PubMed
4-month registry study (2 groups of 30 CVI patients) found Pycnogenol reduced evening leg volume by 18.3% vs 4.4% with elastic compression, with significantly improved skin PO2/PCO2 and lower symptom and VCSS scores (P<0.05); compression was poorly tolerated (12/30 could not complete).
registry study
Belcaro 2025 (registry study, diabetics)
✓ PubMed
8-week registry study in 58 diabetics with CVI (28 Pycnogenol 150 mg/day vs 30 compression controls) showed significant improvement in resting flux, rate of ankle swelling, transcutaneous PO2/PCO2 and symptom/VCSS/VDS scores (P<0.05) with no adverse effects.