Monterey Pine

What Is Monterey Pine?

Monterey pine is a fast-growing three-needled pine from coastal California, valued for its timber and for a bark extract sold as Enzogenol®.

Pinus radiata grows wild in only five small populations: three on the central California coast and two on the Mexican islands of Guadalupe and Cedros ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. It typically reaches 15–30 m in the wild. Planted in the Southern Hemisphere from the nineteenth century onward, it became probably the most widely planted plantation conifer in the world, covering more than 4 million hectares ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

Enzogenol is a water extract of the bark of New Zealand-grown trees ^{2,6Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →}. It is rich in proanthocyanidins, mostly procyanidins ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}. Eight small human studies have looked at memory, recovery after concussion and brain injury, blood sugar after meals and markers of oxidative stress ^{3,4,5,6,7,8,9,17Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →Reference 5Theadom A et al. · 2013RCTEnzogenol for cognitive functioning in traumatic brain injury: a pilot placebo-controlled RCT — phase II randomised controlled trial, n=60View study →Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →Reference 8Walter A et al. · 2017RCTEffect of Enzogenol® supplementation on cognitive, executive and vestibular/balance functioning in the chronic phase of concussion — placebo-controlled trial, n=42View study →Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →Reference 17Chayasirisobhon S · 2013Efficacy of Pinus radiata bark extract and vitamin C combination product as a prophylactic therapy for recalcitrant migraine — open-label study, n=50View study →}.

Enzogenol is a different product from Pycnogenol, the bark extract of maritime pine.

How Is Monterey Pine Used?

• Bark extract (Enzogenol®) — a water extract of the bark, taken as a capsule, often together with vitamin C ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}.
• Needles and resin — not prepared commercially as medicine.

Botany

Monterey pine is an evergreen tree, usually 15–30 m tall and occasionally up to 64 m, with a trunk 30–90 cm across ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. Its crown is broadly conical at first and becomes rounded or flattened with age. The bark is red-brown, turning grey, and furrowed between long scaly ridges ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

The needles grow in bundles of three in the mainland variety and two in the island variety. They are 9–15 cm long, deep yellow-green and finely toothed along the edges, and they stay on the tree for three to four years ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

The seed cones are 7–15 cm long, lopsided and glossy yellow-brown. They ripen two years after pollination and often stay closed on the branch for years. The heat of a forest fire, or sometimes hot weather, opens them and releases the seeds ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

In plantations the tree grows much larger than it does at home. A New Zealand tree planted around 1927 measured 68.7 m tall in 2024, while wild Californian trees seldom pass 40 m ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

Distribution

Monterey pine grows naturally in a coastal fog belt in central California, at 30–400 m, in three places: San Mateo and Santa Cruz counties, Monterey County, and San Luis Obispo County ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. The island variety, var. binata, grows at 600–1,200 m on Isla Guadalupe and Isla Cedros off Baja California ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

The mainland variety is listed as Endangered on the IUCN Red List and the island variety as Vulnerable ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. The three native Californian stands are threatened by pitch canker, a fungal disease introduced from the southeastern United States and found in California in 1986. In some stands 80–90% of trees are infected ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

It has been planted on a large scale in New Zealand, Australia, Chile, Argentina, Kenya, South Africa, Spain and Uruguay. In New Zealand it covers nearly 1.6 million hectares, 88% of the country’s tree plantations ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. It has also escaped from cultivation along the California coast and is naturalising into southern Oregon ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

Enzogenol is made from the bark of New Zealand-grown trees ^{6,9Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →}, so the extract does not draw on the wild populations.

Growing Conditions

Cultivation snapshot for Monterey Pine

Monterey pine is hardy to USDA zone 8, which puts its cold limit between about −12 °C and −7 °C ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}. In the wild it grows in a mild, foggy coastal climate. Its closed cones rely on fire to release seed and regenerate the stand ^{1Reference 1Earle · 2023Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference databaseView study →}.

Grow it yourself

Farm Wiki is our cultivation-focused sister site, also run by Justin Cooke.

How to growComing soon

Find seedsComing soon

Indications

• Cognitive difficulty after mild traumatic brain injury [bark extract] ⚠Caution: One phase II trial found fewer self-reported cognitive failures. Memory tests and other measures did not differ significantly from placebo ⁵.
• Lingering symptoms after sport concussion [bark extract]
• Working memory in older adults [bark extract with vitamin C]
• Blood sugar after meals [bark extract] ⚠Caution: The two crossover trials measured single meals in healthy people. No trial has measured long-term glucose control ^6,9.
• Oxidative stress in smokers [bark extract with vitamin C]
• Migraine prevention [bark extract with vitamin C] ⚠Caution: The only study was open-label, with no placebo group ¹⁷.
• Blood pressure [bark extract with vitamin C] ⚠Caution: The fall in blood pressure came from a pilot study with no placebo group. In a controlled trial in smokers, the extract added nothing to vitamin C for blood-vessel function ^3,4,7.

Pharmacology & Research

Eight human studies of the bark extract have been published, six of them controlled. All were run in New Zealand, Australia or the United States ^{3,4,5,6,7,8,9,17Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →Reference 5Theadom A et al. · 2013RCTEnzogenol for cognitive functioning in traumatic brain injury: a pilot placebo-controlled RCT — phase II randomised controlled trial, n=60View study →Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →Reference 8Walter A et al. · 2017RCTEffect of Enzogenol® supplementation on cognitive, executive and vestibular/balance functioning in the chronic phase of concussion — placebo-controlled trial, n=42View study →Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →Reference 17Chayasirisobhon S · 2013Efficacy of Pinus radiata bark extract and vitamin C combination product as a prophylactic therapy for recalcitrant migraine — open-label study, n=50View study →}.

The rest is preclinical: enzyme inhibition, cell studies, and work in diabetic mice, rodents and chickens ^{10,11,12,13,14,15,16Reference 10Lim WXJ et al. · 2022In vitroThe inhibitory effects of New Zealand pine bark (Enzogenol®) on α-amylase, α-glucosidase and dipeptidyl peptidase-4 — in vitroView study →Reference 11Bang CY · 2014AnimalEnzogenol improves diabetes-related metabolic change in C57BL/KsJ-db/db mice, a model of type 2 diabetes mellitus — animalView study →Reference 12Kim DS et al. · 2010In vitroPine bark extract Enzogenol attenuated tumour necrosis factor-alpha-induced endothelial cell adhesion and monocyte transmigration — in vitroView study →Reference 13Choi YH et al. · 2018Proanthocyanidin-rich Pinus radiata bark extract inhibits mast cell-mediated anaphylaxis-like reactions — animalView study →Reference 14Park IJ et al. · 2013Immunomodulatory effect of a proanthocyanidin-rich extract from Pinus radiata bark by dosing period in chickens — veterinaryView study →Reference 15Park IJ et al. · 2011Effect of proanthocyanidin-rich extract from Pinus radiata bark on immune response of specific-pathogen-free White Leghorn chickens — veterinaryView study →Reference 16Venkatesan T et al. · 2016In vitroPinus radiata bark extract induces caspase-independent apoptosis-like cell death in MCF-7 human breast cancer cells — in vitroView study →}.

1. Cognition

Three controlled trials have tested the extract on cognition.

Sixty adults with persistent cognitive difficulties 3–12 months after a mild traumatic brain injury were randomised to 1,000 mg/day of the extract or placebo for six weeks. All then took the extract for a further six weeks, followed by placebo for four ^{5Reference 5Theadom A et al. · 2013RCTEnzogenol for cognitive functioning in traumatic brain injury: a pilot placebo-controlled RCT — phase II randomised controlled trial, n=60View study →}. Self-reported cognitive failures fell significantly against placebo (mean CFQ difference −6.9, 95% CI −10.8 to −4.1), and the improvement was estimated to continue until about week 11. Working and episodic memory, post-concussive symptoms and mood showed some positive trends but no significant treatment effects. The authors graded it Class IIB evidence.

A double-blind study gave 42 men aged 50–65 with a BMI over 25 either the extract plus vitamin C or vitamin C alone for five weeks ^{4Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →}. Speed of response on spatial working memory and immediate recognition tasks improved in the extract group and not in the vitamin C group. Because vitamin C alone was the comparison, the difference can be attributed to the extract. Blood safety measures were unchanged.

A placebo-controlled trial in 42 student athletes with lingering symptoms after sport concussion found increased frontal-midline theta and decreased parietal theta on EEG after six weeks, along with self-reported reductions in mental fatigue and sleep problems ^{8Reference 8Walter A et al. · 2017RCTEffect of Enzogenol® supplementation on cognitive, executive and vestibular/balance functioning in the chronic phase of concussion — placebo-controlled trial, n=42View study →}.

Gap: ⚠⚠ across all three trials, the results that reached significance were questionnaires, reaction speed or EEG markers. Objective memory scores in the brain-injury trial showed trends without significance, and no finding has been independently replicated.

2. Antioxidant

In a 12-week randomised trial in 44 chronic smokers, 480 mg/day of the extract with 60 mg vitamin C significantly reduced protein carbonyls, a marker of oxidative damage to proteins, compared with vitamin C alone ^{7Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →}.

The activity is attributed to the proanthocyanidins together with the minor flavonoids taxifolin, quercetin and myricetin and the phenolic acids gallic and caffeic acid ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}.

Gap: one controlled biomarker endpoint is not a clinical outcome.

3. Blood Glucose

Two acute crossover trials have tested the extract before a sugar load.

The first, in 25 healthy participants, tested 50 mg and 400 mg against placebo before an oral glucose tolerance test ^{6Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →}. In participants with a monophasic glucose curve, both doses significantly reduced the glucose incremental area under the curve, and 400 mg also lowered the peak and the 2-hour glucose. In participants with a complex curve, the area under the curve did not differ significantly. The authors described the study as exploratory.

A second single-blind randomised crossover trial in 40 healthy adults used a sucrose drink. The 400 mg dose reduced the glucose incremental area under the curve by 14.4%, while 50 mg did not reach significance. Insulin did not change ^{9Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →}.

In vitro the extract inhibits α-amylase, α-glucosidase and dipeptidyl peptidase-4 ^{10Reference 10Lim WXJ et al. · 2022In vitroThe inhibitory effects of New Zealand pine bark (Enzogenol®) on α-amylase, α-glucosidase and dipeptidyl peptidase-4 — in vitroView study →}. In db/db diabetic mice it improved glucose tolerance, lowered HbA1c and raised liver AMPK activity ^{11Reference 11Bang CY · 2014AnimalEnzogenol improves diabetes-related metabolic change in C57BL/KsJ-db/db mice, a model of type 2 diabetes mellitus — animalView study →}.

Gap: ⚠ every human glucose result is a single-meal measurement in healthy people. No trial has measured HbA1c or fasting glucose over time.

4. Anti-Inflammatory

In the smoker trial, the extract plus vitamin C significantly reduced fibrinogen in heavy smokers compared with vitamin C alone ^{7Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →}.

In human umbilical vein endothelial cells, the extract reduced TNF-α-induced adhesion molecules, including E-selectin, in a dose-dependent way. It also reduced monocyte adhesion and migration across the cell layer and blocked NF-κB from entering the nucleus ^{12Reference 12Kim DS et al. · 2010In vitroPine bark extract Enzogenol attenuated tumour necrosis factor-alpha-induced endothelial cell adhesion and monocyte transmigration — in vitroView study →}.

Gap: no human inflammatory endpoint beyond fibrinogen has been measured.

5. Blood Pressure and Endothelium

⚠⚠ The cardiovascular claims rest on the weakest study, and one controlled test did not support them.

A 12-week pilot gave 24 healthy people aged 55–75 480 mg/day of the extract with 240 mg/day vitamin C ^{3Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →}. Body weight, body fat percentage, systolic blood pressure and plasma viscosity all fell significantly, and forearm blood flow rose. There was no placebo group, and the authors stated that the changes need to be confirmed by a placebo-controlled study.

The cognition trial noted a non-significant trend toward lower systolic blood pressure in the extract group ^{4Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →}.

⚠⚠ Where a controlled blood-vessel endpoint was measured, the extract added nothing. Flow-mediated dilation in smokers improved in both the extract-plus-vitamin-C and the vitamin-C-alone groups, with no difference between them ^{7Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →}.

A 2025 meta-analysis of 27 randomised trials of pine bark extracts found small reductions in blood pressure, fasting glucose, HbA1c, body weight and LDL cholesterol ^{18Reference 18Mohammadi S et al. · 2025Meta-analysisDoes supplementation with pine bark extract improve cardiometabolic risk factors? A systematic review and meta-analysis of 27 RCTs — meta-analysisView study →}. The trials pooled were mostly of maritime pine extract.

Gap: the headline cardiovascular findings come from an uncontrolled pilot, and the one controlled blood-vessel endpoint was negative.

6. Preclinical Findings

Mast-cell stabilisation. A proanthocyanidin-rich water extract of P. radiata bark reduced allergic-type skin reactions in mice. In rat mast cells it inhibited histamine release, reduced calcium uptake and raised cyclic AMP ^{13Reference 13Choi YH et al. · 2018Proanthocyanidin-rich Pinus radiata bark extract inhibits mast cell-mediated anaphylaxis-like reactions — animalView study →}.

Immune effects in chickens. Two studies found that a proanthocyanidin-rich bark extract increased the proliferation of blood, spleen and thymus immune cells ^{14,15Reference 14Park IJ et al. · 2013Immunomodulatory effect of a proanthocyanidin-rich extract from Pinus radiata bark by dosing period in chickens — veterinaryView study →Reference 15Park IJ et al. · 2011Effect of proanthocyanidin-rich extract from Pinus radiata bark on immune response of specific-pathogen-free White Leghorn chickens — veterinaryView study →}. One also found raised interferon-γ and lowered IL-6 ^{15Reference 15Park IJ et al. · 2011Effect of proanthocyanidin-rich extract from Pinus radiata bark on immune response of specific-pathogen-free White Leghorn chickens — veterinaryView study →}.

One cancer cell line. The extract caused a caspase-independent, apoptosis-like cell death in MCF-7 breast cancer cells, with lysosomal damage and endoplasmic-reticulum stress and no rise in reactive oxygen species ^{16Reference 16Venkatesan T et al. · 2016In vitroPinus radiata bark extract induces caspase-independent apoptosis-like cell death in MCF-7 human breast cancer cells — in vitroView study →}. The authors called for further work on the mechanism, and there is no animal or human cancer evidence.

Mechanisms

The bark extract is mostly procyanidins, and its proposed activity is antioxidant and anti-inflammatory, studied through free-radical scavenging and NF-κB signalling in endothelial cells ^{2,12Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →Reference 12Kim DS et al. · 2010In vitroPine bark extract Enzogenol attenuated tumour necrosis factor-alpha-induced endothelial cell adhesion and monocyte transmigration — in vitroView study →}.

The effect on blood sugar has been linked to inhibition of the enzymes that digest starch and sugar. That fits the human finding of lower glucose without a change in insulin ^{9,10Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →Reference 10Lim WXJ et al. · 2022In vitroThe inhibitory effects of New Zealand pine bark (Enzogenol®) on α-amylase, α-glucosidase and dipeptidyl peptidase-4 — in vitroView study →}.

Clinical trials

Eight published human studies, six controlled, all in New Zealand, Australia or the United States, all of the bark extract, and none independently replicated. Last checked: September 2026.

Phytochemistry

Enzogenol is made by water extraction of Pinus radiata bark. The dry powder contains more than 80% proanthocyanidins, 1–2% taxifolin, up to 8% other flavonoids and phenolic acids, and 5–10% carbohydrates ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}.

The proanthocyanidins are about 94% procyanidins and 6% prodelphinidins ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}. The minor flavonoids, phenolic acids and stilbenes include catechin, quercetin, myricetin, piceatannol, and gallic, ferulic, caffeic and protocatechuic acid ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}.

The needles carry the monoterpenes α-pinene, β-pinene, Δ3-carene and limonene, whose levels shift with the season ^{19Reference 19Romón P et al. · 2017Seasonal terpene variation in needles of Pinus radiata (Pinales: Pinaceae) trees attacked by Tomicus piniperda (Coleoptera: Scolytinae) and the effect of limonene on beetle aggregation — field chemistry studyView study →}.

The stem and needles of one-year-old seedlings hold diterpene resin acids: abietic, dehydroabietic, levopimaric and palustric, neoabietic, isopimaric, pimaric and sandaracopimaric acids ^{20Reference 20López-Goldar X et al. · 2020Resin acids as inducible chemical defences of pine seedlings against chewing insects — seedling chemistry studyView study →}. Dehydroabietic acid was the most abundant in both, and pimaric acid was not found in the needles ^{20Reference 20López-Goldar X et al. · 2020Resin acids as inducible chemical defences of pine seedlings against chewing insects — seedling chemistry studyView study →}.

Research on other pine bark extracts, including Pycnogenol, should be read separately from studies of Enzogenol ^{18Reference 18Mohammadi S et al. · 2025Meta-analysisDoes supplementation with pine bark extract improve cardiometabolic risk factors? A systematic review and meta-analysis of 27 RCTs — meta-analysisView study →}.

Constituent Summary

The bark extract is the characterised material.

Dosage

All figures are trial doses of the standardised bark extract.

Four of the eight studies gave the extract with vitamin C ^{3,4,7,17Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →Reference 7Young JM et al. · 2006RCTComparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44View study →Reference 17Chayasirisobhon S · 2013Efficacy of Pinus radiata bark extract and vitamin C combination product as a prophylactic therapy for recalcitrant migraine — open-label study, n=50View study →}.

Safety & Pregnancy

The bark extract was well tolerated in every human study, and it has published animal toxicity data.

Full Safety & Interactions Detail

Toxicology. The manufacturer’s toxicology studies found no effects on body weight, blood chemistry, blood counts or organ weights in rats and dogs, and the extract was not mutagenic. The only adverse events were vomiting and diarrhoea in dogs, mostly at the highest dose on an empty stomach. The no-observed-adverse-effect level was 750 mg/kg/day ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}.

Human studies. The same report describes 480 mg/day for six months and 960 mg/day for five weeks with no effect on liver or kidney function or blood counts, and no adverse events ^{2Reference 2Frevel MA et al. · 2012Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicologyView study →}. The brain-injury trial found the extract safe and well tolerated at 1,000 mg/day ^{5Reference 5Theadom A et al. · 2013RCTEnzogenol for cognitive functioning in traumatic brain injury: a pilot placebo-controlled RCT — phase II randomised controlled trial, n=60View study →}. The pilot found no change in any biochemical or blood measure ^{3Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →}. In the migraine study, patients who responded kept taking it for twelve months ^{17Reference 17Chayasirisobhon S · 2013Efficacy of Pinus radiata bark extract and vitamin C combination product as a prophylactic therapy for recalcitrant migraine — open-label study, n=50View study →}.

Glucose-lowering drugs. In vitro the extract inhibits α-amylase, α-glucosidase and dipeptidyl peptidase-4 ^{10Reference 10Lim WXJ et al. · 2022In vitroThe inhibitory effects of New Zealand pine bark (Enzogenol®) on α-amylase, α-glucosidase and dipeptidyl peptidase-4 — in vitroView study →}, the targets of acarbose and the gliptins, and it lowers blood sugar after a meal ^{6,9Reference 6Lim WXJ et al. · 2020RCTAn acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25View study →Reference 9Lim WXJ et al. · 2025RCTThe hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40View study →}. It has not been studied in anyone taking those drugs, so care is reasonable when combining them.

Blood pressure. The falls reported came from an uncontrolled pilot ^{3Reference 3Shand B et al. · 2003Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24View study →} and a non-significant trend ^{4Reference 4Pipingas A et al. · 2008RCTImproved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42View study →}, so no blood-pressure interaction is expected.

Pregnancy, breastfeeding and children. There are no data.

References

1. Earle, C. J. (ed.) (2023). Pinus radiata — species description, native populations, conservation status, plantation extent and pitch canker — reference database. The Gymnosperm Database. https://www.conifers.org/pi/Pinus_radiata.php
2. Frevel MA, Pipingas A, Grigsby WJ, Frampton CM, Gilchrist NL (2012). Production, composition and toxicology studies of Enzogenol® Pinus radiata bark extract — analytical / toxicology. Food Chem Toxicol, 50, 4316-24. https://pubmed.ncbi.nlm.nih.gov/22982471/
3. Shand B, Strey C, Scott R, Morrison Z, Gieseg S (2003). Pilot study on the clinical effects of dietary supplementation with Enzogenol, a flavonoid extract of pine bark, and vitamin C — uncontrolled pilot, n=24. Phytother Res, 17, 490-4. https://pubmed.ncbi.nlm.nih.gov/12748985/
4. Pipingas A, Silberstein RB, Vitetta L, Rooy CV, et al. (2008). Improved cognitive performance after dietary supplementation with a Pinus radiata bark extract formulation — double-blind controlled trial, n=42. Phytother Res, 22, 1168-74. https://pubmed.ncbi.nlm.nih.gov/18683195/
5. Theadom A, Mahon S, Barker-Collo S, McPherson K, et al. (2013). Enzogenol for cognitive functioning in traumatic brain injury: a pilot placebo-controlled RCT — phase II randomised controlled trial, n=60. Eur J Neurol, 20, 1135-44. https://pubmed.ncbi.nlm.nih.gov/23384428/
6. Lim WXJ, Chepulis L, von Hurst P, Gammon CS, Page RA (2020). An acute, placebo-controlled, single-blind, crossover, dose-response, exploratory study to assess the effects of New Zealand pine bark extract (Enzogenol®) on glycaemic responses in healthy participants — crossover trial, n=25. Nutrients, 12, 497. https://pubmed.ncbi.nlm.nih.gov/32075228/
7. Young JM, Shand BI, McGregor PM, Scott RS, Frampton CM (2006). Comparative effects of Enzogenol and vitamin C supplementation versus vitamin C alone on endothelial function and biochemical markers of oxidative stress and inflammation in chronic smokers — randomised controlled trial, n=44. Free Radic Res, 40, 85-94. https://pubmed.ncbi.nlm.nih.gov/16298763/
8. Walter A, Finelli K, Bai X, Arnett P, et al. (2017). Effect of Enzogenol® supplementation on cognitive, executive and vestibular/balance functioning in the chronic phase of concussion — placebo-controlled trial, n=42. Dev Neuropsychol, 42, 93-103. https://pubmed.ncbi.nlm.nih.gov/28452602/
9. Lim WXJ, Page RA, Gammon CS, Moughan PJ (2025). The hypoglycaemic effects of New Zealand pine bark extract on sucrose uptake and glycaemic responses in healthy adults — single-blind randomised placebo-controlled crossover trial, n=40. Nutrients, 17, 2277. https://pubmed.ncbi.nlm.nih.gov/40732901/
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