Cardiovascular Health

Multiple RCTs demonstrate that replacing saturated fat with linoleic acid significantly reduces LDL cholesterol. The AHA recommends 5-10% of calories from omega-6 PUFAs based on consistent trial evidence. An in vitro study confirmed LA modulates cholesterol metabolism in intestinal epithelial cell models.

Multiple RCTs demonstrate that hesperidin, the primary flavonoid in orange peel, reduces systolic and diastolic blood pressure. The active metabolite hesperetin improves vascular tone, with B-grade evidence supporting clinically meaningful blood pressure reductions in mildly hypertensive adults.

Human trials show hesperidin from orange peel improves flow-mediated dilation (FMD), a marker of endothelial function. The hesperetin metabolite enhances nitric oxide bioavailability, though the number of well-powered trials remains limited.

In hyperlipidemic mouse models, Chinese hawthorn extract consistently reduced total cholesterol, LDL, and triglycerides across multiple studies. Mechanisms include PPARα upregulation in liver and inhibition of HMG-CoA reductase transcription via NF-κB signaling. No controlled human trials identified.

Reviews suggest that the balance of dietary electrolytes—particularly the sodium-to-potassium ratio, along with adequate magnesium and calcium—plays a role in blood pressure regulation. Higher potassium intake relative to sodium is associated with lower blood pressure, though evidence for combined electrolyte supplementation as a strategy is limited compared to single-mineral studies.

One uncontrolled Chinese clinical study (n=60) found Apocynum venetum leaf extract significantly reduced systolic blood pressure from 171 to 148 mmHg and diastolic from 98 to 89 mmHg over 8 weeks (P<0.01). Multiple animal studies in spontaneously hypertensive, renal hypertensive, and NaCl-fed hypertensive rats demonstrate consistent blood pressure reduction. Mechanistic studies show the extract inhibits angiotensin II-induced vasoconstriction via nitric oxide release and superoxide scavenging.

One uncontrolled Chinese clinical study (n=40 hyperlipidemic patients) found Apocynum venetum leaf extract significantly increased HDL-C from 47.5 to 63.9 mg/dL (P<0.01). The review literature reports lipid-lowering as a traditional use, but no controlled human trials have been conducted for this outcome.

Two small RCTs found MitoQ (20 mg/day for 4-6 weeks) improved brachial artery flow-mediated dilation. Rossman et al. (2018) reported a 42% improvement in FMD in 20 healthy older adults, while Kirkman et al. (2023) showed significant FMD improvement in 18 patients with chronic kidney disease. Rossman also found reduced aortic stiffness in participants with elevated baseline levels.

A 6-month randomized, controlled, crossover trial in 48 postmenopausal women found that daily grapefruit juice consumption (containing ~210 mg naringenin glycosides) significantly reduced carotid-femoral pulse wave velocity, indicating decreased arterial stiffness (PMID 26016866). Preclinical studies in hypercholesterolemic mice show naringin reduces atherosclerotic plaque progression by 41% (PMID 21684135).

In 10 healthy volunteers, 1L of pink grapefruit juice produced peak QTc prolongation of 12.5 +/- 4.2 ms at 5 hours via HERG channel blockade; naringenin was the most potent flavonoid inhibitor among 10 tested (PMID 15710766). In 32 participants including cardiomyopathy patients, grapefruit juice significantly increased QT variability indices comparable to sotalol (PMID 18433709). This represents a cardiac safety concern, particularly for patients with structural heart disease.

An RCT in metabolic syndrome (n=100) found curcuminoids + 10 mg piperine significantly reduced LDL-C, triglycerides, total cholesterol, and Lp(a), while raising HDL-C. A standalone piperine RCT in NAFLD (n=68) similarly showed significant lipid improvements. Additional RCTs in type 2 diabetes (n=100, n=71) showed triglyceride reductions with curcumin-piperine combinations.

Flavanols increase nitric oxide bioavailability and improve flow-mediated dilation, a validated marker of endothelial function. EFSA approved the health claim that 200mg cocoa flavanols daily helps maintain endothelium-dependent vasodilation. Bioavailability studies confirm gastrointestinal absorption of flavan-3-ols relevant to in vivo vascular effects.

An in vitro study demonstrated dose-dependent inhibition of angiotensin converting enzyme (ACE) by flavan-3-ols and procyanidins, providing a mechanistic basis for blood pressure reduction. The EFSA-approved vascular elasticity claim and documented nitric oxide pathway activation support clinical relevance of this effect.

In dyslipidemic rat models, L. acidophilus supplementation demonstrated potential benefits on lipid profiles. Limited human evidence suggests possible modest cholesterol-lowering effects, though effect sizes are small. The mechanism may involve bile salt hydrolase activity and cholesterol assimilation by the probiotic.

Limited evidence suggests triglyceride reduction. Udani et al. (2004) found a trend toward triglyceride reduction (-26.3 mg/dL vs -8.2 mg/dL placebo, p=0.07) in a small 8-week RCT (n=27). Ramirez-Jimenez et al. (2022) found a 37.8% triglyceride decrease with a Phaseolus vulgaris-based snack bar in hypertriglyceridemic women (n=26, p=0.032), though this used a whole-bean food rather than pure extract.

Reduced cardiovascular mortality with higher dietary intake (epidemiological)

Human pharmacokinetic and pharmacodynamic studies confirm that danshen compounds potentiate the effects of antiplatelet agents including clopidogrel and aspirin. A rat study (PMID:30710735) demonstrated altered pharmacokinetics of dual antiplatelet therapy. This effect is both potentially therapeutic and a significant drug interaction safety concern, particularly with warfarin.

A single-blind randomized placebo-controlled trial (n=40) found 3g/day of N. jatamansi for 4 weeks significantly reduced systolic BP from 144 to 134 mmHg and diastolic BP from 95 to 83 mmHg vs. placebo in stage 1 hypertension patients.

In preclinical models, salidroside protected H9c2 cardiomyocytes from ischemia/reperfusion-induced apoptosis and inhibited platelet function and thrombus formation through AKT/GSK3β signaling. Endothelial cell protection via NLRP3 inhibition and autophagy enhancement has also been demonstrated.

In vitro studies show L-alanine consistently activates AMPK in rat, mouse, and human hepatocytes, reducing glucose output via an insulin-independent mechanism. In alloxan-induced diabetic rats, L-alanine supplementation improved blood glucose levels and biochemical indices, but no human supplementation trials exist.

In rodent models, haskap berry polyphenols decreased plasma LDL and total cholesterol in obese Zucker rats, normalized serum lipid levels in hypercholesterolemic rats, and activated SIRT1 to promote cholesterol efflux and inhibit macrophage foam cell formation in vitro. No human lipid data available.

In a small pilot crossover RCT in 20 older adults, a single 400 mg anthocyanin dose of haskap berry extract produced a significant acute reduction in diastolic blood pressure and heart rate at 1.5 hours post-consumption. No chronic supplementation data available.

Multiple in vitro and animal studies demonstrate higenamine increases cardiac contractile force (positive inotropy). In isolated guinea pig papillary muscle, higenamine shifted the calcium curve leftward and enhanced isoproterenol-induced responses. In porcine ventricular myocardial cells, it increased action potential amplitude and duration by activating slow calcium channels, and abolished potassium-induced conduction blocks. Additional studies in cultured rat heart cells and guinea pig heart failure models confirmed cardiotonic properties via beta-adrenergic agonism. No human data exists.

In isolated mouse right atria, higenamine produced positive chronotropic effects (increased heart rate) via beta-1 adrenergic receptor activation. Acetylcholine physiologically antagonized this heart-rate-increasing effect, with cholera toxin pretreatment accentuating the antagonism. Cultured rat heart cell studies also indexed chronotropic activity. All evidence is from animal tissue preparations with no human data.

A single animal study examined the effects of demethylcoclaurine (alongside ginsenosides) on hemodynamic parameters in dogs under experimentally induced septic shock. The compound was classified as a cardiotonic beta-adrenergic agonist. No abstract or detailed results are available in English, and no human studies exist for this application.

In spontaneously hypertensive rats, an ethanolic extract of mulberry fruit reduced blood pressure and attenuated vascular remodeling (PMID:29771623). Only a single animal study is available.

Preclinical evidence and reviews indicate NAD+ homeostasis is disrupted in failing hearts and that NAD+ supplementation may prevent adverse cardiac remodeling by improving mitochondrial redox state (Mericskay, 2016; Pei et al., 2022). The Nampt/NAD axis has been shown to suppress atrial fibrillation by modulating calcium handling in cellular models (Shan et al., 2020). No human cardiac trials have been completed.

In rodent and cell models, 7,8-DHF alleviated cardiac fibrosis via circadian signal restoration, counteracted cardiac hypertrophy through AMPK activation, rescued rotenone-induced cardiomyocyte cytotoxicity, and attenuated cisplatin-induced cardiomyocyte apoptosis via the p53/Nrf2 pathway.

Preclinical studies show myricetin protects cardiomyocytes from LPS-induced injury in cell models. Review articles summarize protective effects against cardiovascular disease markers in animal and in vitro systems. No human clinical trials have evaluated cardiovascular endpoints.

Preclinical studies show piceatannol promotes nitric oxide release via eNOS phosphorylation in human endothelial cells (PMID:26367737), inhibits PDGF-BB-induced smooth muscle cell proliferation via PI3K inhibition (PMID:19887493), and demonstrates antiarrhythmic effects in a whole-heart long QT syndrome model (PMID:28606656). A pharmacological review supports multiple cardiovascular-protective mechanisms (PMID:24919577).

In vitro and preclinical studies found that elevated BCAAs (including valine) promoted endothelial dysfunction through increased reactive oxygen species and inflammation. A 2020 study showed BCAA catabolism enhanced thrombosis risk via platelet propionylation. These are mechanistic findings; clinical relevance to supplemental valine in healthy individuals is unknown.

A single preclinical study in conscious and anaesthetized dogs examined the effects of IV COP on haemodynamics and cardiac metabolism, providing early evidence of cardiovascular activity. No human replication or oral bioavailability data exists.

A small clinical trial in healthy volunteers found that dietary supplementation with combined omega-3 and omega-6 fatty acids reduced induced white blood cell aggregation, suggesting improved microvascular flow properties.

One small human RCT using a combination product (loquat + olive leaf extract) showed 14.3% cholesterol reduction with supplement alone and 24% with statin co-administration over 3 months. Animal studies show triterpene acid and flavonoid fractions reduce total cholesterol and triglycerides in diabetic models. Human evidence is confounded by combination product.

In vitro, paprika carotenoids efficiently suppressed copper-catalyzed oxidation of human blood LDL particles, inhibiting conjugated diene formation and blocking conversion of cholesterol into atherogenic products including 5,6-epoxycholesterol and 7-ketocholesterol. Also reduced formation of small dense LDL subfractions. No human intervention trials have tested this effect in vivo.

A single study identified antiplatelet principles from clove, showing eugenol and related compounds inhibit thromboxane synthesis and platelet aggregation via prostaglandin pathway modulation. No human clinical trials evaluating cardiovascular or anticoagulant effects.

No effect

In hyperlipidemic rats, hederagenin reduced total cholesterol, triglycerides, LDL-C, and MDA while increasing HDL-C, SOD, and GSH-PX via p38 MAPK pathway inhibition. A separate rat atherosclerosis model confirmed reductions in serum lipids comparable to atorvastatin (positive control).

In rodent models, D-limonene diminished CCl4-induced cardiac toxicity by alleviating oxidative stress and inflammatory markers. One small human study found that olfactory stimulation with grapefruit essential oil (rich in limonene) affected autonomic neurotransmission and blood pressure.

In a 7-week animal study, Tulbaghia violacea root methanolic extract (50 mg/kg) reduced systolic blood pressure by 12.88% in Dahl salt-sensitive rats, with increased sodium excretion and lower ACE activity compared to captopril control.

In a diabetic rat model, Tulbaghia violacea extract reduced serum triglycerides, VLDL, and total cholesterol while increasing HDL-cholesterol, along with reduced liver enzyme markers (ALT, AST) suggesting hepatoprotective effects.

A 2020 systematic review identified 21 studies (3 human, 18 animal) on squalene and cardiovascular risk. In animal models, 15 of 18 studies reported positive effects on lipid profiles, potentially via HMG-CoA reductase inhibition similar to statins. However, only 1 of 3 human studies showed a positive effect, and the reviewers concluded evidence remains insufficient for definitive claims.

In female Sprague-Dawley rats, dietary calcium D-glucarate reduced total serum cholesterol by up to 14% and LDL-cholesterol by up to 35% with no effect on HDL. Preliminary uncontrolled human observations have been referenced in reviews but no peer-reviewed human clinical trials have been published.

In hypercholesterolemic Wistar rats, methanolic seed extract of Celastrus paniculatus (65 mg/kg) substantially reduced plasma total cholesterol, triglycerides, and LDL cholesterol while increasing HDL, with results comparable to standard hypolipidemic drugs. Mechanism may involve HMG-CoA reductase inhibition and elevated lipoprotein lipase activity.

In an animal thrombosis model, fennel essential oil (30 mg/kg orally for 5 days) provided 70% protection against collagen-epinephrine-induced paralysis, and trans-anethole provided 83% protection, without the prohemorrhagic side effects seen with aspirin. Mechanisms involved antiplatelet activity, clot destabilization, and vasodilation.

A single open-label trial in 8 aging HIV patients found improved endothelial dysfunction markers after 12 weeks of GlyNAC supplementation. No controlled trials have replicated this finding.

In a preclinical study of 21-month-old mice, 12 weeks of GlyNAC-enriched diet improved cardiometabolic enzyme activity and diastolic function in males but not females. Female mice showed a decline in exercise performance, indicating sex-differential effects.

In isolated rat vasa deferentia, hordenine (25 μM) potentiated contractile responses to submaximal noradrenaline and inhibited responses to tyramine, consistent with noradrenaline reuptake inhibition. Hordenine did not directly produce tissue contractions, suggesting indirect sympathomimetic activity rather than direct adrenergic agonism.

A single RCT in 100 postmenopausal women (Bristow et al., 2014) found microcrystalline hydroxyapatite produced significantly less acute serum calcium spike compared to calcium citrate and calcium carbonate, while equally reducing PTH and favorably affecting bone turnover markers at 3 months. This blunted calcium spike may have cardiovascular safety implications, though this has not been directly tested.

In an in vitro study using collagen-stimulated human platelets, S. tenuifolia extract potently inhibited platelet aggregation, calcium mobilization, granule secretion, and fibrinogen binding to integrin alphaIIb-beta3 via suppression of MAPK and Akt signaling. No in vivo or human studies have been conducted.

An open-label pilot study (n=24, ages 55-75) found significant reductions in systolic blood pressure after 12 weeks of 480mg Enzogenol plus 240mg vitamin C. However, the study lacked placebo control and the co-administered vitamin C confounds attribution.

An open-label pilot study (n=24) reported increased basal and hyperaemic blood flow in forearm resistance vessels and reduced plasma viscosity after 12 weeks supplementation. Findings are preliminary due to lack of placebo control and vitamin C co-administration.

A single animal study demonstrated that OEA suppresses intimal hyperplasia after balloon injury in rats through the AMPK/PPARα signaling pathway (PMID:29305859). No human data available for this cardiovascular outcome.

In diabetic KK-Ay mice, palmatine decreased serum total cholesterol and triglycerides while increasing HDL cholesterol. These lipid-modulating effects parallel berberine but appear weaker. No human clinical data are available.

A 1964 preclinical study examined the effects of 3-epi-alpha-yohimbine (rauwolscine) on the sympathetic nervous system, consistent with its known alpha-2 adrenergic antagonist mechanism. Evidence is limited to this single early pharmacological investigation with no modern human replication.

Mixed effect

In animal models, ethanolic extract (500 mg/kg) ameliorated isoproterenol-induced myocardial damage. Studies in cholesterol-fed rabbits showed anti-atherogenic activity with liver cholesterol decreased by 50% and heart cholesterol by 60%. One RCT protocol for coronary artery disease adjunct therapy is registered but results not yet available.

Notable Protection

Moderate Improvement

Humanin protects cardiomyocytes, endothelial cells, and fibroblasts from oxidative stress, reducing ischemia-reperfusion injury and atherosclerosis progression.

Circulating humanin levels are positively associated with preserved coronary endothelial function in clinical observations.

Reduces infarct volume and preserves cardiac function in preclinical models. Promotes cardiomyocyte survival and migration. Multiple animal studies show significant improvement.

Small Increase

Small Improvement (animal data)