{"url":"https://whatshealthyandwhy.com/nattokinase/cardiovascular-fibrinolysis","path":"/nattokinase/cardiovascular-fibrinolysis","alternates":{"json":"https://whatshealthyandwhy.com/api/articles/nattokinase/cardiovascular-fibrinolysis.json","markdown":"https://whatshealthyandwhy.com/nattokinase/cardiovascular-fibrinolysis.md"},"topic":{"slug":"nattokinase","name":"Nattokinase","url":"https://whatshealthyandwhy.com/nattokinase"},"slug":"cardiovascular-fibrinolysis","order":1,"title":"Cardiovascular and Fibrinolytic Benefits","question":"Does nattokinase lower blood pressure and help prevent blood clots?","answer":"Nattokinase probably lowers blood pressure slightly (about 3–6 mmHg systolic in trials), while clot-dissolving and plaque benefits in people are less certain.","description":"How nattokinase, a fermented soy enzyme, supports heart health by dissolving blood clots and lowering blood pressure","confidence":4,"confidenceNote":"A six-trial meta-analysis (546 people) shows small blood pressure drops; clot and plaque benefits rest on mechanisms and one open-label study.","evidenceSummary":{"rctCount":2,"observationalCount":1,"metaAnalysisCount":1,"totalParticipants":"1,200+","replicated":true,"newestStudyYear":2023},"category":{"categoryTitle":"What's Good For You","categorySlug":"good-for-you","subcategoryName":"Supplements & Vitamins","subcategorySlug":"supplements","url":"https://whatshealthyandwhy.com/explore/good-for-you/supplements"},"actions":["Trials used about 2,000 FU (100 mg) daily for 8 weeks; look for capsules standardized to fibrinolytic activity (commonly 2,000 FU) [1].","Choose a vitamin K2-free product, since natto's natural K2 may interact with anticoagulants like warfarin.","Consider it mainly if you have pre-hypertension or stage 1 hypertension, where evidence is strongest, and treat it as adjunctive to medical care [5]."],"cautions":["Nattokinase has real blood-thinning effects; if you take warfarin, aspirin, clopidogrel or other anticoagulants, consult your physician first, as bleeding risk can rise.","No randomized trial has shown fewer heart attacks or strokes; most trials lasted only 8–12 weeks."],"simpleText":"Nattokinase is a protein-digesting enzyme derived from natto, a traditional Japanese fermented soybean food. It has a unique ability to break down fibrin — the protein that forms blood clots — and has been shown in multiple clinical trials to lower blood pressure and reduce cardiovascular risk markers [1][3]. Unlike most dietary enzymes that are destroyed by digestion, nattokinase survives the gut and reaches the bloodstream intact, making it one of the few oral enzymes with documented systemic effects [2].","mediumText":"How Nattokinase Works\n\nNattokinase is a serine protease produced by the bacterium Bacillus subtilis var. natto during the fermentation of soybeans. Its primary mechanism is fibrinolytic: it directly cleaves fibrin, the insoluble protein mesh that forms the structural scaffold of blood clots. Unlike prescription thrombolytics (clot-dissolving drugs) that must be injected, nattokinase is stable enough to be absorbed through the intestinal wall and maintain activity in the circulation [3].\n\nBeyond direct fibrinolysis, nattokinase also activates the body's own plasmin system — the natural pathway for dissolving clots — and inhibits platelet aggregation. Together these effects reduce blood viscosity and the tendency toward pathological clotting without fully suppressing normal clot formation [3].\n\nBlood pressure effects appear to be mediated at least partly through renin inhibition. Renin is an enzyme that initiates a hormonal cascade (the renin-angiotensin system) that raises blood pressure. A controlled trial found that nattokinase reduced renin activity by 1.17 ng/mL/h in addition to lowering blood pressure values [1].\n\nDosing and Forms\n\nNattokinase is typically measured in fibrinolytic units (FU) rather than milligrams. Standard research doses have ranged from 2,000 FU to 10,800 FU per day:\n\n- 2,000 FU/day was used in the landmark Korean blood pressure trial [1]\n- 100 mg/day (approximately 2,000 FU) was used in the North American multicenter trial [2]\n- 10,800 FU/day was used in the large Chinese atherosclerosis study [4]\n\nSupplements are widely available as capsules standardized to activity levels (commonly 2,000 FU per capsule). Look for products that have removed vitamin K2, which is naturally present in natto but may interact with anticoagulant medications like warfarin.\n\nImportant caution: Nattokinase has real blood-thinning effects. People taking warfarin, aspirin, clopidogrel, or other anticoagulants should consult their physician before use, as the combination can increase bleeding risk.\n\nWho May Benefit Most\n\nThe strongest evidence is for people with elevated blood pressure (pre-hypertension or stage 1 hypertension) and those with cardiovascular risk factors including elevated cholesterol, early atherosclerosis, or a family history of blood clots. The enzyme naturally occurs in natto, and populations with high natto consumption historically have lower rates of cardiovascular mortality — though dietary pattern and genetics confound this observation.\n\nSee our fermented foods page for more on natto as a whole food and its broader nutritional profile.","deepText":"Evidence Review\n\nBlood Pressure: Randomized Controlled Trials\n\nThe foundational clinical trial on nattokinase and blood pressure was conducted by Kim et al. (2008), a randomized, double-blind, placebo-controlled study of 86 Korean adults with untreated systolic blood pressure of 130–159 mmHg [1]. Participants received either nattokinase (2,000 FU/capsule) or placebo for 8 weeks. Compared to the control group, the nattokinase group showed net reductions of -5.55 mmHg systolic and -2.84 mmHg diastolic (both p < 0.05). Renin activity also fell by -1.17 ng/mL/h in the treatment group, suggesting a renin-angiotensin system mechanism [1].\n\nJensen et al. (2016) extended these findings to a North American population in a multicenter, randomized, double-blind, placebo-controlled trial of 79 subjects with elevated blood pressure who consumed 100 mg nattokinase (NSK-SD, vitamin K2-free) or placebo daily for 8 weeks [2]. This is important because prior evidence came largely from Asian populations. The study confirmed blood pressure reductions in a Western cohort, with reductions more robust in male participants. Nattokinase also significantly reduced von Willebrand factor — a protein involved in platelet adhesion and a marker of endothelial dysfunction — suggesting vascular wall benefits beyond simple pressure reduction [2].\n\nMeta-Analysis Summary\n\nA 2023 systematic review and meta-analysis by Li et al. synthesized data from six randomized controlled trials encompassing 546 participants [5]. Nattokinase supplementation significantly reduced:\n\n- Systolic blood pressure: -3.45 mmHg (MD, 95% CI reported)\n- Diastolic blood pressure: -2.32 mmHg (MD, 95% CI reported)\n\nThe meta-analysis found that nattokinase significantly reduced blood pressure but showed no lipid benefit: relatively low total doses had a negative effect on total, HDL and LDL cholesterol, relatively high total doses still gave a higher total cholesterol than control, triglycerides showed no significant association, and blood glucose rose slightly; the authors cautioned that relatively low-dose nattokinase may have no significant lipid-lowering effect. The authors concluded that nattokinase can serve as effective adjunctive therapy for hypertension management [5].\n\nAtherosclerosis and Lipids: Large-Scale Clinical Study\n\nChen et al. (2022) conducted a prospective clinical study of 1,062 participants taking 10,800 FU nattokinase per day for 12 months to assess effects on atherosclerosis progression and lipid profiles [4]. Significant findings included:\n\n- Reduced carotid artery intima-media thickness (a surrogate marker for atherosclerosis)\n- Decreased carotid plaque size\n- Improvement in total cholesterol, LDL cholesterol, and triglyceride levels\n\nThe study's large sample size and 12-month duration give it meaningful statistical power, though the lack of blinding (it was an open-label observational study) limits causal inference. Nonetheless, the magnitude of the atherosclerosis findings is notable and consistent with the enzyme's known fibrinolytic and anti-inflammatory mechanisms [4].\n\nFibrinolytic Mechanism: Review Evidence\n\nWeng et al. (2017) published a comprehensive mechanistic review of nattokinase as an oral antithrombotic agent [3]. Key points from their analysis:\n\n- Nattokinase demonstrates direct fibrinolytic activity comparable to plasmin in vitro, and retains activity after oral absorption in humans\n- It activates endogenous tissue plasminogen activator (tPA) and urokinase, amplifying the body's own fibrinolytic system\n- The enzyme inhibits platelet aggregation through multiple pathways, including reduction of thromboxane B2\n- A pharmacokinetic study confirmed the enzyme survives gastrointestinal digestion and achieves detectable fibrinolytic activity in plasma following a single oral dose\n\nLimitations and Evidence Gaps\n\nThe overall evidence base for nattokinase is promising but has important limitations:\n\n- Most trials are short (8–12 weeks), and long-term cardiovascular outcome data (heart attacks, strokes) are not yet available from randomized trials\n- The large Chinese atherosclerosis study used observational design, limiting causal conclusions\n- Optimal dosing is still being established; effective doses across studies range from 2,000 to 10,800 FU/day\n- Drug interaction studies with anticoagulants are limited; caution is warranted for anyone on blood-thinning medications\n\nOn balance, the evidence supports nattokinase as a well-tolerated, bioavailable supplement with genuine effects on blood pressure and fibrinolytic markers. The effect sizes are modest but clinically relevant, particularly for people in the borderline-hypertensive range looking for non-pharmacological support.","deepTruncated":false,"references":[{"id":"1","title":"Effects of nattokinase on blood pressure: a randomized, controlled trial","authors":"Kim JY, Gum SN, Paik JK, Lim HH, Kim KC, Ogasawara K, Inoue K, Park S, Jang Y, Lee JH","year":2008,"journal":"Hypertension Research","pmid":"18971533","url":"https://pubmed.ncbi.nlm.nih.gov/18971533/"},{"id":"2","title":"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","authors":"Jensen GS, Lenninger M, Ero MP, Benson KF","year":2016,"journal":"Integrated Blood Pressure Control","pmid":"27785095","url":"https://pubmed.ncbi.nlm.nih.gov/27785095/"},{"id":"3","title":"Nattokinase: An Oral Antithrombotic Agent for the Prevention of Cardiovascular Disease","authors":"Weng Y, Yao J, Sparks S, Wang KY","year":2017,"journal":"International Journal of Molecular Sciences","pmid":"28264497","url":"https://pubmed.ncbi.nlm.nih.gov/28264497/"},{"id":"4","title":"Effective management of atherosclerosis progress and hyperlipidemia with nattokinase: A clinical study with 1,062 participants","authors":"Chen H, Chen J, Zhang F, Li Y, Wang R, Zheng Q, Zhang X, Zeng J, Xu F, Lin Y","year":2022,"journal":"Frontiers in Cardiovascular Medicine","pmid":"36072877","url":"https://pubmed.ncbi.nlm.nih.gov/36072877/"},{"id":"5","title":"Nattokinase Supplementation and Cardiovascular Risk Factors: A Systematic Review and Meta-Analysis of Randomized Controlled Trials","authors":"Li X, Long J, Gao Q, Pan M, Wang J, Yang F, Zhang Y","year":2023,"journal":"Reviews in Cardiovascular Medicine","pmid":"39076715","url":"https://pubmed.ncbi.nlm.nih.gov/39076715/"}],"wordCount":1079,"source":{"path":"src/content/topics/nattokinase/cardiovascular-fibrinolysis.md"},"citeAs":"“Does nattokinase lower blood pressure and help prevent blood clots?.” What's Healthy and Why. https://whatshealthyandwhy.com/nattokinase/cardiovascular-fibrinolysis","notice":"General information backed by peer-reviewed research, not medical advice."}