Ingredient Guide
French Maritime Pine Bark: Benefits, Dosage, and What the Research Says
A polyphenol-rich bark extract with decades of clinical research behind it - here is what the evidence actually says.
Written by Jessica Medson
French Maritime Pine Bark is a standardized polyphenol extract derived from the bark of Pinus pinaster, a pine native to the Atlantic coast of southern France. A 2024 systematic review of 39 placebo-controlled trials in 2,009 participants found signals of benefit across circulatory health, cognitive function, skin integrity, and exercise recovery, though Cochrane-level analyses note that most individual trials were small and evidence for specific conditions remains limited. Research suggests it may help support healthy venous circulation, normal antioxidant defenses, and cognitive performance within the normal range - with the circulation evidence being the most consistent across studies.
What Is French Maritime Pine Bark?
French Maritime Pine Bark extract comes from the outer bark of Pinus pinaster, a pine tree native to the Mediterranean coastal regions of southern France, Spain, and Portugal. The bark has been used in folk medicine for centuries; modern interest accelerated in the 1960s when researchers began isolating and characterizing its active compounds.
The extract is concentrated in a family of water-soluble polyphenols - primarily proanthocyanidins (also called condensed tannins or OPCs) - alongside phenolic acids including caffeic acid, ferulic acid, and taxifolin. These compounds account for the majority of its documented biological activity and are responsible for the extract's characteristic dark reddish-brown color and astringent taste.
The most extensively researched commercial form is Pycnogenol, derived specifically from Pinus pinaster trees growing in the Landes de Gascogne forest along the French Atlantic coast. By 2024, over 450 published studies reference this extract, including 39 randomized, double-blind, placebo-controlled trials involving 2,009 participants across health outcomes spanning cardiovascular, cognitive, joint, skin, and sports performance endpoints.1
French Maritime Pine Bark is often grouped with other OPC-rich extracts such as grape seed extract. While both contain proanthocyanidins, they come from different plant sources with distinct polyphenol profiles. The research database for Pinus pinaster bark is substantially larger than for most other pine bark species, making cross-product extrapolation unreliable.
Supplements are sold as capsules or tablets, typically standardized to a minimum proanthocyanidin content (often 65-70% OPCs by weight). Look for products that declare standardization clearly on the label.
How Does It Work?
French Maritime Pine Bark extract acts through several overlapping biological mechanisms that have been characterized in both laboratory and clinical settings.
Antioxidant activity
Proanthocyanidins are potent free-radical scavengers. Beyond direct neutralization, research suggests they also stimulate the body's intrinsic antioxidant enzyme systems - one pharmacological review described a doubling of intracellular antioxidant enzyme synthesis alongside free-radical scavenging.14 In human trials, supplementation consistently lowered markers of oxidative stress such as plasma free radicals and F2-isoprostanes (a validated lipid peroxidation marker) relative to placebo.9
Nitric oxide and endothelial support
The extract appears to stimulate endothelial nitric oxide synthase (eNOS), increasing nitric oxide (NO) production in blood vessel walls. NO is a key vasodilator that helps maintain normal blood flow and supports healthy endothelial function. A placebo-controlled trial in 58 hypertensive patients found that 100 mg/day for 12 weeks significantly decreased endothelin-1 (a vasoconstrictor peptide) and increased vasodilatory prostaglandins compared to placebo - measurable signs of improved endothelial activity.13
Anti-inflammatory signaling
Proanthocyanidins inhibit NF-kB-driven inflammatory cascades and reduce circulating leukotrienes and interleukins. This mechanism helps explain studied effects on joint comfort, airway reactivity, and periodontal tissue.1415
Extracellular matrix and connective tissue support
The extract binds to and stabilizes collagen and elastin fibers in connective tissue, contributing to its studied effects on skin elasticity and vascular wall integrity. In a controlled skin study, supplementation upregulated gene expression for both collagen type I synthesis and hyaluronic acid synthase, pointing to direct molecular support of skin structural proteins.11
Circulation and Vascular Health: What the Evidence Shows
The most consistent body of clinical evidence for French Maritime Pine Bark concerns venous circulation and leg edema - swelling caused by excess fluid accumulation in tissues, often linked to chronic venous insufficiency (CVI). This is the area where the research signal is strongest and most reproducible across research groups.
What the research shows
A double-blind, placebo-controlled randomized trial enrolled 40 patients with CVI and leg varices, assigning them to 300 mg/day Pycnogenol or placebo for two months. Approximately 60% of those in the treated group experienced complete disappearance of edema by the end of the trial, with significant reductions in leg pain and heaviness compared to placebo - assessed at both 30 and 60 days.5
A subsequent 98-subject prospective controlled study compared three arms: Pycnogenol 150 mg/day alone, elastic compression stockings alone, and the combination. At eight weeks, Pycnogenol alone outperformed compression stockings alone on all measured parameters - including ankle swelling, transcutaneous oxygen levels, and venous pressure scores. The combination produced the best results overall, and no side effects were documented in any treatment arm.6
A 2014 comprehensive narrative review of clinical evidence concluded that the extract demonstrates "strong antioxidant, anti-inflammatory and vasodilator activities, antithrombotic effects and collagen stabilizing properties" relevant to venous health outcomes, including reduction of edema and support for venous ulcer healing.16
A 2024 review of all 39 placebo-controlled human trials also documented a 32% improvement in flow-mediated dilation - a validated clinical marker of endothelial health - across the cardiovascular subset of studies.1
What about blood pressure?
Here the picture is more nuanced and requires honest reporting. A 2020 PRISMA-compliant meta-analysis - the most rigorously conducted analysis available - examined seven randomized, double-blind, placebo-controlled trials covering 626 participants and found no statistically significant effect on systolic blood pressure, diastolic blood pressure, mean arterial pressure, or pulse pressure compared to placebo.4 Consumers should not rely on French Maritime Pine Bark as a substitute for clinically indicated blood pressure treatment.
A separate placebo-controlled trial found that 100 mg/day for 12 weeks allowed some hypertensive patients to reduce their calcium antagonist dose under medical supervision - a clinically interesting but highly preliminary finding requiring physician oversight.13
Two Cochrane systematic reviews - the gold standard for evidence synthesis - concluded that across the full evidence base, small sample sizes, limited numbers of trials per condition, and variable study quality mean that definitive conclusions for specific clinical conditions are not yet possible.23 The circulation and edema findings are the most consistently positive area.
Cognitive Performance and Mental Clarity
A growing number of small but controlled human trials suggest French Maritime Pine Bark may help support attention, memory, and executive function. This research spans healthy younger adults, working-age professionals, and older adults with elevated oxidative stress.
What the research shows
An eight-week controlled study in 53 healthy university students (ages 18-27) found that 100 mg/day of the extract improved sustained attention, memory, executive function, and mood ratings compared to a control group. Students in the supplemented group also had a lower university exam failure rate (approximately 6% vs. approximately 11% in controls).8 While the academic performance finding is exploratory given the small sample, the cognitive battery improvements were statistically significant.
A 12-week controlled study in 59 healthy professionals aged 35-55 using 150 mg/day found significant improvements on a cognitive test battery including pattern recognition memory and spatial working memory, alongside a median 30.4% reduction in plasma free radicals vs. a negligible 0.9% change in controls - suggesting the cognitive benefit tracks with measurable antioxidant activity.7
In an older population, a three-month double-blind, placebo-controlled trial enrolling 101 adults aged 60-85 and using 150 mg/day found improved working memory performance and decreased F2-isoprostane concentrations (a lipid peroxidation marker) in the treated group relative to controls. Lipid profile did not change significantly, focusing the interpretation on antioxidant-mediated cognitive support.9
A 2019 narrative review of the broader Pycnogenol evidence base concluded that spatial memory in older individuals is "significantly ameliorated" and connects these effects to the extract's antioxidative and anti-inflammatory activity in neural tissue.15
Important caveats
Most cognitive trials in this area were conducted by overlapping research groups, used relatively small samples (typically under 60 subjects per arm), and were conducted without pre-registration. Independent replication in larger, pre-registered trials would substantially strengthen these findings. The consistent direction of effect across different age groups is notable, but the strength of evidence is best characterized as promising rather than definitive. Research suggests French Maritime Pine Bark may help support normal cognitive function - particularly in individuals with elevated oxidative stress - rather than providing a confirmed nootropic effect in all users.
Skin Health and Antioxidant Protection
French Maritime Pine Bark has been studied for skin applications in three areas: photoprotection, hyperpigmentation, and structural support (elasticity and hydration). Evidence is early-stage but biologically plausible.
What the research shows
A 12-week randomized study in 20 healthy postmenopausal women found that oral Pycnogenol supplementation significantly improved skin hydration and elasticity. Researchers measured a significant increase in hyaluronic acid synthase-1 mRNA expression and upregulation of collagen type I gene expression - two molecular markers directly linked to skin structural support and moisture retention. Effects were most pronounced in women with baseline dry skin.11
A 2016 clinical and molecular evidence review concluded that French Maritime Pine Bark intake "may be used to reduce hyperpigmentation of human skin and improve skin barrier function and extracellular matrix homeostasis." Proposed mechanisms include antioxidant protection against UV-induced reactive oxygen species and direct effects on melanin synthesis pathways.10
The 2024 review of 39 placebo-controlled trials reported a 13% improvement in skin elasticity across the skin health trial subset, along with improvements in hair density at six months.1
Most skin studies used 100-150 mg/day for 8-12 weeks. These were small trials with limited follow-up, and the evidence base for skin outcomes should not be overstated. Oral supplementation is not a substitute for topical photoprotection, and dramatic anti-aging claims are not supported by the current evidence.
Exercise Recovery and Athletic Performance
A smaller set of controlled studies has examined French Maritime Pine Bark in physically active adults. Results are positive but come from small trials that warrant cautious interpretation.
What the research shows
A controlled study enrolled 147 subjects and evaluated supplementation effects in two parts: military fitness testing (Army Physical Fitness Test) and a 100-minute triathlon. In the triathlon segment, subjects taking 150 mg/day completed the event in a mean time of 89 minutes 44 seconds versus 96 minutes 5 seconds in controls. The supplemented group also showed better post-exercise metabolic recovery and decreased oxidative stress markers following exertion.12
The 2024 review of all placebo-controlled trials noted that cycling endurance increased by 80 seconds in the relevant trial subset, and post-exercise free radical increases were substantially blunted in supplemented subjects compared to controls.1
The proposed mechanism is consistent with the extract's documented antioxidant effects: intense exercise generates significant oxidative stress, and reducing this burden may support faster recovery. These findings are intriguing but should be viewed as preliminary. Most sports performance trials used 150 mg/day during active training. Athletes seeking ergogenic support should discuss supplementation with a sports medicine professional and be aware that larger, independently conducted trials are not yet available.
Safety, Side Effects, and Interactions
French Maritime Pine Bark extract has a generally favorable short-term safety profile in healthy adults at studied doses (50-300 mg/day for up to six months). However, safety data from long-term use and in vulnerable populations remain limited.
Common, mild adverse effects
- Gastrointestinal discomfort (nausea, stomach upset) - most commonly when taken on an empty stomach; taking with a meal typically reduces this
- Headache or dizziness - infrequent in trials
- Mild mouth irritation - rare, particularly with chewable forms
A 2020 Cochrane review of 27 trials noted that adverse event reporting was inconsistent across studies, limiting conclusions about overall safety. Long-term safety data (beyond six months) are insufficient.3
Drug interactions - consult your provider before combining
- Anticoagulants and antiplatelet drugs (warfarin, aspirin, clopidogrel, heparin): French Maritime Pine Bark may mildly inhibit platelet aggregation. Combining with blood thinners may increase bleeding risk. Do not combine without medical supervision.
- Antihypertensive medications: The extract has documented vasodilatory effects via NO and endothelin modulation.13 Combining with blood pressure drugs could produce additive effects. Monitor blood pressure if combining.
- Diabetes medications (insulin, metformin, sulfonylureas): Some evidence suggests modest effects on fasting glucose.15 Combining may produce additive glucose-lowering effects. Monitor blood glucose and inform your healthcare provider.
- Immunosuppressants: The extract's immune-modulating activity may theoretically interfere with immunosuppressive therapies such as cyclosporine or tacrolimus.
Populations requiring caution
- Pregnancy and breastfeeding: Insufficient safety data exist. Avoid use during pregnancy or lactation unless a healthcare provider has specifically assessed the risk-benefit balance for your situation.
- Children: Most trials enrolled adults. ADHD data in children are limited and judged by Cochrane reviewers as insufficient to support use.2 Do not use in children without medical guidance.
- Autoimmune conditions: Due to potential immune modulation, individuals with autoimmune conditions (lupus, rheumatoid arthritis, multiple sclerosis) should consult a physician before use.
- Upcoming surgery: Due to potential antiplatelet effects, consider stopping at least two weeks before elective surgery. Inform your surgical team about all supplements you take.
This supplement is not intended to diagnose, treat, cure, or prevent any disease. Always inform your healthcare provider about all supplements you take, especially if you are on prescription medications or have a chronic health condition.
French Maritime Pine Bark Dosage Guide
The following doses reflect those used in the human clinical trials summarized in this article. They are provided for informational purposes only. Consult a healthcare provider before starting supplementation, especially if you take medications.
| Goal | Typical Dose | Timing | Notes |
|---|---|---|---|
| General antioxidant and circulatory support | 100 mg/day | Once daily with a meal | Dose used in the Liu et al. (2004) hypertensive patient trial; common starting point in multiple study designs |
| Chronic venous insufficiency / leg edema | 150 mg/day | Divided doses with meals (e.g., 50 mg three times daily) | Dose used in the 98-subject Cesarone et al. (2010) controlled study; some trials used up to 300 mg/day in the acute phase |
| Cognitive performance support | 100-150 mg/day | Once daily or in two divided doses with meals | 100 mg used in student trial (Luzzi 2011); 150 mg used in professional (Belcaro 2014) and elderly (Ryan 2008) trials; most studies ran 8-12 weeks |
| Skin elasticity and hydration | 100-150 mg/day | Once daily with a meal | Marini et al. (2012) RCT in postmenopausal women used this range for 12 weeks; effects on collagen/HA gene expression observed at 12 weeks |
| Athletic performance and exercise recovery | 150 mg/day | Once daily during active training periods | Vinciguerra et al. (2013) triathlon study used 150 mg/day; timing relative to exercise was not specified in the study protocol |
Start at the lower end of the range and take with food to minimize GI discomfort. Most clinical benefits in trials appeared at 8-12 weeks of consistent use. Safety beyond six months of continuous use has not been well established in controlled trials.
French Maritime Pine Bark Evidence at a Glance
A summary of the key outcomes studied in human clinical trials, with honest characterization of the strength of available evidence.
| Outcome | Key Finding from Human Research | Evidence Level |
|---|---|---|
| Chronic venous insufficiency / leg edema | ~60% edema resolution in a double-blind RCT at 300 mg/day; 150 mg/day outperformed compression stockings alone in a 98-subject study | Tier A - Multiple RCTs; most consistent evidence area |
| Blood pressure | A 2020 PRISMA meta-analysis of 7 RCTs (626 participants) found NO statistically significant reduction in SBP or DBP | Tier A - Null result; do not rely on for BP management |
| Endothelial / vascular function | 100 mg/day for 12 weeks reduced endothelin-1 and increased vasodilatory prostaglandins vs. placebo in hypertensive patients; flow-mediated dilation improved 32% across cardiovascular trial subset | Tier A - Small RCTs; promising signal |
| Cognitive performance (students and professionals) | Improved sustained attention, memory, and executive function in 8-12 week controlled studies; 30.4% reduction in plasma free radicals in the professional study | Tier A - Small RCTs; consistent direction; needs independent replication |
| Cognitive function (older adults 60-85) | Improved working memory and decreased lipid peroxidation biomarkers vs. placebo over 3 months (101-subject RCT) | Tier A - Single RCT; promising but preliminary |
| Skin elasticity and hydration | Significant improvement in elasticity and hydration with upregulation of collagen type I and hyaluronic acid synthase gene expression in a 12-week RCT (n=20 postmenopausal women) | Tier A - Very small RCT; early-stage evidence |
| Athletic endurance and recovery | Triathlon completion time improved by ~6 minutes vs. controls; post-exercise oxidative stress markers blunted in supplemented group | Tier A - Small controlled study; independent replication lacking |
| Oxidative stress markers (broad) | Consistently reduces plasma free radicals and F2-isoprostanes across diverse trial populations | Tier A - Most replicated finding across studies |
Tier A = human RCT or meta-analysis. 'Small RCT' indicates n typically under 100 per arm. Cochrane reviews (2012, 2020) note that across all conditions, evidence is insufficient for definitive clinical conclusions due to small sample sizes and variable study quality.
Frequently Asked Questions
What is French Maritime Pine Bark good for?
French Maritime Pine Bark (also sold as Pycnogenol) is most consistently studied for supporting healthy leg circulation and reducing edema, with multiple controlled trials showing reduced ankle swelling in people with chronic venous insufficiency. Smaller controlled trials also suggest possible benefits for cognitive performance, skin elasticity, and exercise recovery, though evidence in these areas is more preliminary.
How much French Maritime Pine Bark should I take per day?
Most clinical trials used 100-150 mg/day, taken with meals to reduce stomach upset. Some venous insufficiency trials used up to 300 mg/day. Start at 100 mg/day and consult a healthcare provider before going higher, especially if you take blood thinners, blood pressure medications, or diabetes drugs.
Is French Maritime Pine Bark the same as Pycnogenol?
Pycnogenol is the most widely researched brand name of French Maritime Pine Bark extract, standardized from Pinus pinaster trees in the Landes de Gascogne forest of France. Generic pine bark extracts may use the same species or related pines, but the research database - over 450 published studies - is specific to the Pycnogenol standardized extract.
Does French Maritime Pine Bark lower blood pressure?
The evidence is mixed and honest reporting requires caution here. A 2020 PRISMA-compliant meta-analysis of seven randomized trials covering 626 participants found no statistically significant reduction in systolic or diastolic blood pressure. Some smaller individual trials found modest effects. Do not use this supplement as a replacement for clinically prescribed blood pressure treatment.
What are the side effects of French Maritime Pine Bark?
Most trials report mild side effects including gastrointestinal discomfort (nausea, stomach upset - especially on an empty stomach), occasional headache, and rare mouth irritation. Taking it with food typically reduces digestive issues. More serious interactions are possible with blood thinners, antihypertensives, and diabetes medications, so always inform your healthcare provider.
Is French Maritime Pine Bark safe to take long term?
Short-term use (up to six months) at studied doses of 50-300 mg/day appears generally well tolerated in healthy adults. However, a 2020 Cochrane review noted that long-term safety data are insufficient due to inconsistent adverse event reporting across studies. There is not enough evidence to characterize safety beyond six months of continuous use.
Can French Maritime Pine Bark improve memory and focus?
Small controlled trials in students (8 weeks, 100 mg/day), working professionals (12 weeks, 150 mg/day), and adults aged 60-85 (3 months, 150 mg/day) each found improvements in attention, working memory, and executive function. The consistent directional effect across age groups is notable, but most trials were small and conducted by overlapping research groups - independent, larger trials are needed.
Can you take French Maritime Pine Bark during pregnancy?
No - there is insufficient safety data for use during pregnancy or breastfeeding. Avoid use unless a healthcare provider has specifically reviewed the risk-benefit balance for your individual situation. This applies to most polyphenol-based supplements for which pregnancy trials have not been conducted.
Does French Maritime Pine Bark interact with blood thinners?
Yes, potentially. French Maritime Pine Bark may have mild platelet-inhibiting effects. Combining it with anticoagulants (warfarin) or antiplatelet drugs (aspirin, clopidogrel) could theoretically increase bleeding risk. If you take blood thinners, consult your physician or pharmacist before adding this supplement. Also consider stopping two weeks before any planned surgery.
How long does French Maritime Pine Bark take to work?
In most clinical trials, measurable changes in circulatory markers and symptom scores appeared at four to eight weeks, with continued improvement through 12 weeks. Cognitive trials typically ran 8-12 weeks before effects were statistically detectable. Consistent daily use with meals is important - sporadic dosing was not evaluated in the available RCTs.
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Scientific References
- 1.Weichmann F, Rohdewald P Pycnogenol French maritime pine bark extract in randomized, double-blind, placebo-controlled human clinical studies. Frontiers in Nutrition. 2024. PubMed: 38757130Clinical (RCT / meta-analysis)
- 2.Schoonees A, Visser J, Musekiwa A, Volmink J Pycnogenol (extract of French maritime pine bark) for the treatment of chronic disorders. Cochrane Database of Systematic Reviews. 2012. PubMed: 22513958Clinical (RCT / meta-analysis)
- 3.Robertson NU, Schoonees A, Brand A, Visser J Pine bark (Pinus spp.) extract for treating chronic disorders. Cochrane Database of Systematic Reviews. 2020. PubMed: 32990945Clinical (RCT / meta-analysis)
- 4.Fogacci F, Tocci G, Sahebkar A, Presta V, Banach M, Cicero AFG Effect of Pycnogenol on Blood Pressure: Findings From a PRISMA Compliant Systematic Review and Meta-Analysis of Randomized, Double-Blind, Placebo-Controlled, Clinical Studies. Angiology. 2020. PubMed: 31763928Clinical (RCT / meta-analysis)
- 5.Arcangeli P Pycnogenol in chronic venous insufficiency. Fitoterapia. 2000. PubMed: 10844161Clinical (RCT / meta-analysis)
- 6.Cesarone MR, Belcaro G, Rohdewald P, Pellegrini L, Ledda A, Vinciguerra G, Ricci A, Ippolito E, Fano F, Dugall M, Cacchio M, Di Renzo A, Hosoi M, Stuard S, Corsi M Improvement of signs and symptoms of chronic venous insufficiency and microangiopathy with Pycnogenol: a prospective, controlled study. Phytomedicine. 2010. PubMed: 20579863Clinical (RCT / meta-analysis)
- 7.Belcaro G, Luzzi R, Dugall M, Ippolito E, Saggino A Pycnogenol improves cognitive function, attention, mental performance and specific professional skills in healthy professionals aged 35-55. Journal of Neurosurgical Sciences. 2014. PubMed: 24675223Clinical (RCT / meta-analysis)
- 8.Luzzi R, Belcaro G, Zulli C, Cesarone MR, Cornelli U, Dugall M, Hosoi M, Feragalli B Pycnogenol supplementation improves cognitive function, attention and mental performance in students. Panminerva Medica. 2011. PubMed: 22108481Clinical (RCT / meta-analysis)
- 9.Ryan J, Croft K, Mori T, Wesnes K, Spong J, Downey L, Kure C, Lloyd J, Stough C An examination of the effects of the antioxidant Pycnogenol on cognitive performance, serum lipid profile, endocrinological and oxidative stress biomarkers in an elderly population. Journal of Psychopharmacology. 2008. PubMed: 18701642Clinical (RCT / meta-analysis)
- 10.Grether-Beck S, Marini A, Jaenicke T, Krutmann J French Maritime Pine Bark Extract (Pycnogenol) Effects on Human Skin: Clinical and Molecular Evidence. Skin Pharmacology and Physiology. 2016. PubMed: 26492562Human observational
- 11.Marini A, Grether-Beck S, Jaenicke T, Weber M, Burki C, Formann P, Brenden H, Schonlau F, Krutmann J Pycnogenol effects on skin elasticity and hydration coincide with increased gene expressions of collagen type I and hyaluronic acid synthase in women. Skin Pharmacology and Physiology. 2012. PubMed: 22270036Clinical (RCT / meta-analysis)
- 12.Vinciguerra G, Belcaro G, Bonanni E, Cesarone MR, Rotondi V, Ledda A, Hosoi M, Dugall M, Cacchio M, Cornelli U Evaluation of the effects of supplementation with Pycnogenol on fitness in normal subjects with the Army Physical Fitness Test and in performances of athletes in the 100-minute triathlon. Journal of Sports Medicine and Physical Fitness. 2013. PubMed: 24247188Clinical (RCT / meta-analysis)
- 13.Liu X, Wei J, Tan F, Zhou S, Wurthwein G, Rohdewald P Pycnogenol, French maritime pine bark extract, improves endothelial function of hypertensive patients. Life Sciences. 2004. PubMed: 14659974Clinical (RCT / meta-analysis)
- 14.Rohdewald P A review of the French maritime pine bark extract (Pycnogenol), a herbal medication with a diverse clinical pharmacology. International Journal of Clinical Pharmacology and Therapeutics. 2002. PubMed: 11996210Human observational
- 15.Rohdewald PJ Pleiotropic Effects of French Maritime Pine Bark Extract to Promote Healthy Aging. Rejuvenation Research. 2019. PubMed: 30215292Human observational
- 16.Gulati OP Pycnogenol in chronic venous insufficiency and related venous disorders. Phytotherapy Research. 2014. PubMed: 23775628Human observational