Nattokinase and coenzyme Q10 (CoQ10) both appear on supplement shelves under the heart-health banner, yet they work through mechanisms so different that comparing them is genuinely apples to oranges. Nattokinase is a serine protease enzyme extracted from natto, a traditional Japanese fermented soybean food, that directly degrades fibrin and stimulates the body’s own plasminogen activators and, in lab and animal studies, breaks down fibrin clots [3][4]. CoQ10 is a fat-soluble electron carrier embedded in the inner mitochondrial membrane, shuttling electrons between respiratory complexes to generate ATP and acting as a lipophilic antioxidant. Neither compound works like the other, and understanding that distinction is the first step toward using either intelligently.
This article breaks down the proposed mechanism of each compound, summarizes what human evidence actually exists, outlines the populations most often studied, and flags the safety concerns that matter most, particularly the serious drug interactions associated with nattokinase. Nothing here constitutes medical advice; anyone managing a cardiovascular condition should speak with a physician before adding either supplement to their routine.
Key Takeaways
- Nattokinase works by breaking down fibrin and stimulating the body’s own clot-dissolving proteins; this is a completely different mechanism from CoQ10’s role in mitochondrial electron transport.
- CoQ10 supports cellular energy production in the heart through the mitochondrial respiratory chain, and research suggests CoQ10-class compounds can maintain electron flow even when Complex I is impaired [1].
- Disrupted NAD+/NADH redox balance in the heart worsens cardiac dysfunction [2], placing CoQ10 within a broader mitochondrial context relevant to cardiac energy metabolism.
- Nattokinase has serious drug interaction potential with anticoagulants and antiplatelet agents and should be discontinued at least one week before any surgical procedure.
- Both supplements have early, small-trial human evidence but neither has demonstrated reductions in hard cardiovascular outcomes like heart attack or stroke in large randomized trials.
How Nattokinase Works: A Fibrin-Targeting Enzyme
Nattokinase is produced when Bacillus subtilis bacteria ferment soybeans to make natto. The enzyme belongs to the serine protease family, meaning it cleaves protein bonds using a catalytically active serine residue. Its primary substrate is fibrin, the insoluble protein scaffold that gives blood clots their structure. By breaking fibrin into soluble degradation products, nattokinase dissolved fibrin clots in laboratory assays and prevented artery occlusion in rats, but this has not been shown in people [3][4].
Beyond direct fibrinolysis, nattokinase appears to upregulate endogenous plasminogen activators, the body’s own clot-dissolving proteins including tissue plasminogen activator (tPA) and urokinase. Small randomized trials in human subjects have documented measurable changes in fibrinolytic markers in plasma after supplementation, and blood pressure results are mixed: an 8-week trial found systolic fell 5.55 mmHg more than placebo, a later trial found only diastolic fell with systolic not different from placebo, and a 3-year trial in healthy adults found no effect [5][6][7]. The blood-pressure effect is not fully explained; one trial pointed to lower renin activity, while a 3-year trial found no effect on arterial stiffness or blood pressure [5][7]. Because the supporting human trials are short-term and involve relatively few participants, these effects should be understood as preliminary rather than established.
How CoQ10 Works: Mitochondrial Electron Transport and Redox Balance
CoQ10 (ubiquinone) sits at the intersection of mitochondrial energy production and antioxidant defense. In its oxidized form it accepts electrons from NADH-dependent Complex I and FADH2-dependent Complex II, then passes them to Complex III. This electron relay is the engine of oxidative phosphorylation, the process that generates the majority of cardiac ATP. The heart is among the most metabolically active tissues in the body, making adequate CoQ10 availability particularly relevant to cardiac function.
Research note: A 2024 meta-analysis of CoQ10 in heart failure found lower all-cause mortality (RR = 0.64) [17].
Research using idebenone, a synthetic short-chain analog of CoQ10 designed to penetrate mitochondria more readily, has illuminated an important nuance of this pathway. In an ischemia/reperfusion model, cardioprotective effects of idebenone were found to be independent of reactive-oxygen-species scavenging and were instead attributed to the compound’s ability to donate electrons directly to Complex III, effectively bypassing a dysfunctional Complex I [1]. This finding is mechanistically significant: it suggests that CoQ10-class compounds can maintain electron flow even when upstream respiratory complexes are impaired, a scenario common in ischemic or metabolically stressed cardiac tissue.
A separate line of evidence ties CoQ10’s relevance to the broader context of cardiac NAD+ metabolism. Experimental work in diabetic cardiomyopathy has shown that NAD+/NADH redox imbalance exacerbates systolic and diastolic dysfunction in the hearts of diabetic mice [2]. Because CoQ10 works in tight concert with the NAD+/NADH couple at Complex I, perturbations in either the coenzyme or the redox ratio compound one another, a relationship that may help explain why CoQ10 depletion is observed in various forms of heart failure.
The Evidence Base: What Human Studies Actually Show
For nattokinase, the human trial record is growing but still limited. Studies have generally enrolled dozens to low hundreds of participants, run for weeks to a few months, and measured surrogate endpoints such as fibrinogen, D-dimer, blood pressure, and arterial stiffness rather than hard cardiovascular outcomes like heart attack or stroke. No large phase-III trial has demonstrated that nattokinase reduces major adverse cardiac events. Demonstrating a biomarker change is not the same as demonstrating clinical benefit, and this distinction matters enormously when evaluating supplement claims.
CoQ10 in heart failure looks helpful in one trial and two reviews, but Cochrane found no convincing evidence either way
CoQ10's heart failure results lean positive, but a Cochrane review found no convincing evidence either way.
Different measures in people with heart failure taking CoQ10, as labelled. This is CoQ10 evidence only, not a comparison with nattokinase. Source: Mortensen et al., JACC Heart Failure 2014; Al Saadi et al., Cochrane Database of Systematic Reviews 2021; Xu et al., BMC Cardiovascular Disorders 2024.
Data table
| Comparison | Estimate | 95% CI |
|---|---|---|
| Q-SYMBIO, 420 patients, long-term composite endpoint (hazard ratio) | 0.50 | 0.32 to 0.80 |
| Cochrane review, all-cause mortality, 1 study of 420 (risk ratio) | 0.58 | 0.35 to 0.95 |
| Later meta-analysis, all-cause mortality (risk ratio) | 0.64 | 0.48 to 0.85 |
Embed this chart
Free to reuse on your site. Copy the code below; please keep the credit link.
The longest placebo-controlled trial, in 265 healthy adults taking 2,000 FU for a median of 3 years, found no slowing of carotid artery thickening or stiffening compared with placebo [7].
CoQ10 has a longer clinical research history, particularly in the context of heart failure and statin-associated myopathy. The most frequently cited trial, Q-SYMBIO, reported no significant changes in its short-term endpoints, but a lower long-term composite cardiovascular endpoint (15% versus 26% on placebo) in 420 patients with moderate to severe heart failure taking CoQ10 100 mg three times daily for 2 years [8], though that trial has methodological limitations and has not been fully replicated. Statin medications inhibit the same mevalonate pathway that produces CoQ10 endogenously, so supplementation in statin users is frequently discussed, though evidence that replenishment improves clinical outcomes in this group remains inconsistent.
A Cochrane review found CoQ10 probably reduces all-cause mortality in heart failure, but this came from one study of 420 participants, and the review concluded there is currently no convincing evidence to support or refute CoQ10 for heart failure [16].
In summary, both compounds have a plausible mechanistic rationale and early supportive human data, but neither has the evidence base of an FDA-approved cardiovascular drug. Claims that either supplement treats or cures heart disease are not substantiated by the available data, and the FDA has not evaluated either compound for treating, curing, or preventing any disease.
Cardiovascular Applications: Matching Mechanism to Need
Because nattokinase acts on fibrin and platelet aggregation pathways, it is most often discussed in the context of thrombotic risk, including concerns about blood viscosity, arterial clot formation, and related biomarkers. People interested in supporting healthy circulation or who have been told they have elevated fibrinogen may find the proposed mechanism relevant. It is also discussed for blood pressure support, where the modest trial data suggest a small average effect on systolic and diastolic readings.
CoQ10, with its mitochondrial energy focus, is most often discussed in populations where cellular energy metabolism in the heart may be compromised: people with heart failure, those taking statins, older adults whose endogenous CoQ10 synthesis declines with age, and people with conditions involving oxidative stress. The connection between mitochondrial electron transport and cardiac contractile function, illustrated by the Complex I bypass mechanism identified with idebenone [1], provides a biologically coherent reason why maintaining adequate CoQ10 could matter for cellular energy production in the heart. Similarly, research highlighting how NAD+/NADH imbalance aggravates diabetic cardiomyopathy [2] places CoQ10 within a broader mitochondrial redox context relevant to cardiac health.
Nattokinase and CoQ10 address different physiological concerns and are not interchangeable. Taking both does not create synergy simply by virtue of both being labeled ‘heart health.’ If anything, their mechanisms are so distinct that they would need to be evaluated independently for any given individual’s situation.
Safety and Drug Interactions: The Non-Negotiables
Nattokinase carries meaningful safety considerations that CoQ10 does not share. Because it enhances fibrinolysis, has shown antiplatelet activity in lab and animal studies, and a Health Canada licence advises against use with products that affect coagulation, nattokinase should not be combined [9][4][10] with anticoagulants such as warfarin, heparin, or direct oral anticoagulants, or with antiplatelet drugs such as aspirin, clopidogrel, or ticagrelor, without physician supervision. Human interaction data are lacking, but one case report describes a cerebellar hemorrhage in a patient also taking aspirin, with causation unproven [11][12]. Anyone scheduled for surgery should discontinue nattokinase at least one week beforehand. People with a history of bleeding disorders, hemorrhagic stroke, or active peptic ulcer disease should avoid it unless specifically cleared by a physician.
CoQ10 is generally well tolerated. Its most clinically relevant interaction is with warfarin: CoQ10 has structural similarities to vitamin K2 and has been reported to reduce warfarin’s anticoagulant effect in some individuals, potentially requiring dose adjustment. This interaction is modest in magnitude and inconsistent across individuals, but warfarin users should inform their prescriber before starting CoQ10. CoQ10 is also fat-soluble, so absorption is meaningfully improved when taken with a meal containing fat; this is a practical consideration rather than a safety concern.
Practical Considerations: Dosing, Form, and Quality
Nattokinase is typically expressed in fibrinolytic units (FU) rather than milligrams, because enzymatic activity rather than mass determines potency. Doses in human trials have ranged from 1,200 to 8,000 FU daily [13]. Product quality varies considerably; look for supplements standardized to fibrinolytic units with third-party testing, as enzyme activity can degrade with poor storage or manufacturing practices.
CoQ10 is available in two forms: ubiquinone (the oxidized form) and ubiquinol (the reduced antioxidant form). Ubiquinol is often marketed as superior for older adults or those with absorption difficulties, though comparative bioavailability data are mixed. Typical trial doses have ranged from 100 to 400 mg daily. As noted, fat co-ingestion substantially improves absorption of either form, and dosing with dinner is a practical default for most users.
🛒 Where to Buy Nattokinase
- Doctor’s Best Nattokinase 2,000 FU
capsules, 100 mg NSK-SD per vcap (2,000 FU): Nattokinase from an established supplement brand; vegetarian capsules; 90 count - NOW Foods Nattokinase 100 mg
capsules, 100 mg per vcap (2,000 FU): Mainstream brand with third-party GMP-certified manufacturing; affordable entry-level option; 90 vcaps; widely available - Source Naturals Nattokinase 100 mg
capsules, 100 mg per tablet (2,000 FU): Long-established supplement brand; competitive pricing at 60 tablets; good for budget-conscious buyers familiar with the brand - Healthy Origins Nattokinase 2,000 FU
capsules, 100 mg per vcap (2,000 FU): Best cost-per-serving option on Amazon; 180 vcap bottle; uses NSK-SD ingredient; popular bulk buy for long-term users
As an Amazon Associate we earn from qualifying purchases. Nattokinase is sold on an enzymatic activity claim, and independent testing has repeatedly found bottles delivering well under their labelled potency. Check that the label states fibrinolytic units (FU) per capsule rather than milligrams alone, and prefer a brand that will supply a batch-specific certificate of analysis showing the measured FU result for that lot, since GMP certification alone does not verify it.
A Note on the Evidence
Both nattokinase and CoQ10 are sold as dietary supplements and have not been evaluated by the FDA to treat, cure, or prevent any disease; supporting human trials are generally small, short-term, and measure surrogate endpoints rather than hard cardiovascular outcomes. Nattokinase in particular carries significant bleeding risk when combined with anticoagulants or antiplatelet medications, should be discontinued at least one week before any surgical procedure, and must not be used as a substitute for prescribed cardiovascular therapy without physician supervision.
Frequently Asked Questions
Can I take nattokinase and CoQ10 together?
There is no known direct pharmacological interaction between nattokinase and CoQ10 specifically. The more important question is whether either is appropriate given your other medications: nattokinase may interact with blood thinners and antiplatelet drugs (human interaction data are lacking, but a Health Canada licence advises against combining it with products that affect coagulation), and CoQ10 may modestly affect warfarin dosing. Always disclose all supplements to your physician before combining them with any prescribed cardiovascular therapy [11][9].
Does nattokinase replace blood thinners like warfarin or aspirin?
No. Nattokinase has fibrinolytic activity, but it has not been studied as a replacement for anticoagulant therapy in conditions such as atrial fibrillation, deep vein thrombosis, pulmonary embolism, or mechanical heart valves. Stopping a prescribed anticoagulant in favor of nattokinase could be life-threatening. Never alter anticoagulant or antiplatelet therapy without physician guidance.
Why do some heart failure patients take CoQ10?
The heart has extremely high ATP demands, and CoQ10 is central to mitochondrial energy production via the electron transport chain. Research on idebenone, a CoQ10 analog, found cardioprotective effects tied to its ability to maintain electron flow through the respiratory chain even when Complex I is impaired [1]. Additionally, work in diabetic cardiomyopathy shows that disrupted NAD+/NADH redox balance in the heart worsens contractile dysfunction [2], and CoQ10 operates within the same mitochondrial redox network, providing a plausible rationale for supplementation in metabolically compromised cardiac tissue.
Does CoQ10 interact with any heart medications?
CoQ10 has structural similarities to vitamin K and may modestly reduce the effectiveness of warfarin in some individuals, potentially requiring dose monitoring and adjustment by the prescribing physician. It does not carry the same additive bleeding risk profile as nattokinase when combined with anticoagulants. Patients on any cardiovascular medication should inform their doctor before starting CoQ10.
How long does nattokinase take to show effects on fibrinolytic markers?
A single-dose crossover trial in 12 healthy young men saw D-dimer rise at 6 and 8 hours, and an uncontrolled 2-month study saw fibrinogen fall, but a 3-year trial in 265 healthy adults found no significant effect on any laboratory measure tested. There is no established timeline for any clinical cardiovascular benefit, and long-term effects have not been adequately studied in controlled trials [14][15][7].
Is CoQ10 useful if I am on a statin?
Statins inhibit the mevalonate pathway, which is also required for endogenous CoQ10 synthesis, leading to measurable reductions in plasma CoQ10 levels. Whether supplementing CoQ10 improves clinical outcomes in statin users, particularly statin-associated muscle symptoms, remains an area of active debate with inconsistent evidence across trials. Discuss with your prescribing physician whether supplementation is appropriate for your specific situation before starting.
References
- Perry JB et al. Cardioprotective effects of idebenone do not involve ROS scavenging: Evidence for mitochondrial complex I bypass in ischemia/reperfusion injury. Journal of molecular and cellular cardiology (2019). PMID 31445917
- Chiao YA et al. NAD(+) Redox Imbalance in the Heart Exacerbates Diabetic Cardiomyopathy. Circulation. Heart failure (2021). PMID 34374300
- Tetsumei Urano et al. The Profibrinolytic Enzyme Subtilisin NAT Purified fromBacillus subtilis Cleaves and Inactivates Plasminogen Activator Inhibitor Type 1. Journal of Biological Chemistry (2001). PMID 11325965
- Ja‐Young Jang et al. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation. Laboratory Animal Research (2013). PMID 24396387
- Kim JY et al. Effects of nattokinase on blood pressure: a randomized, controlled trial. Hypertension research : official journal of the Japanese Society of Hypertension (2008). PMID 18971533
- Jensen GS et al. Consumption of nattokinase is associated with reduced blood pressure and von Willebrand factor, a cardiovascular risk marker: results from a randomized, double-blind, placebo-controlled, multicenter North American clinical trial. Integrated blood pressure control (2016). PMID 27785095
- Hodis HN et al. Nattokinase atherothrombotic prevention study: A randomized controlled trial. Clinical hemorheology and microcirculation (2021). PMID 33843667
- Mortensen SA et al. The effect of coenzyme Q10 on morbidity and mortality in chronic heart failure: results from Q-SYMBIO: a randomized double-blind trial. JACC. Heart failure (2014). PMID 25282031
- Health Canada Licensed Natural Health Product NPN 80089299: Nattokinase 100 mg. Health Canada (2026). source
- Jae-Bum Kim et al. Evaluation of Nattokinase for Antithrombotic Effect and Pharmacological Efficacy by a Biological Test and Clinical Trial. KSBB Journal (2011). doi:10.7841/ksbbj.2011.26.5.393
- Chen H et al. Nattokinase: A Promising Alternative in Prevention and Treatment of Cardiovascular Diseases. Biomarker insights (2018). PMID 30013308
- Chang YY et al. Cerebellar hemorrhage provoked by combined use of nattokinase and aspirin in a patient with cerebral microbleeds. Internal medicine (Tokyo, Japan) (2008). PMID 18310985
- Li X et al. Nattokinase Supplementation and Cardiovascular Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Reviews in cardiovascular medicine (2023). PMID 39076715
- Yuko Kurosawa et al. A single-dose of oral nattokinase potentiates thrombolysis and anti-coagulation profiles. Scientific Reports (2015). PMID 26109079
- European Food Safety Authority (EFSA NDA Panel) Safety of fermented soybean extract NSK-SD as a novel food pursuant to Regulation (EC) No 258/97. European Food Safety Authority (EFSA NDA Panel) (2016). source
- Al Saadi T et al. Coenzyme Q10 for heart failure. The Cochrane database of systematic reviews (2021). PMID 35608922
- Xu J et al. Efficacy and safety of coenzyme Q10 in heart failure: a meta-analysis of randomized controlled trials. BMC cardiovascular disorders (2024). PMID 39462324
These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Content is for informational purposes only and is not medical advice; consult a qualified healthcare provider before starting any supplement. As an Amazon Associate we earn from qualifying purchases.
