Nattokinase
Useful mainly for adults seeking modest blood-pressure support; investigational for circulation.
Quick decision guide
May help most
adults seeking modest blood-pressure support; investigational for circulation
Common dosing range
100–200 mg/day (2,000–4,000 fibrinolytic units)
When to expect effects
Weeks
Watch out for
increases bleeding risk; avoid with anticoagulants and stop 2 weeks before surgery
What is it
Nattokinase is a fibrinolytic enzyme isolated from natto, a traditional Japanese fermented soybean food made with Bacillus subtilis natto. It is marketed primarily for cardiovascular support, including effects on fibrin breakdown, blood pressure, and circulation.
Is it worth it for you?
Use this as a quick fit check, not a diagnosis.
Worth considering if…
Probably skip if…
Evidence at a glance
| Goal | Effect | Best fit | Time |
|---|---|---|---|
blood pressure reduction Good Evidence | Modest, ~a few mmHg systolic | adults with mildly elevated blood pressure | Weeks |
fibrinolytic / circulation support Limited Evidence | Measurable shifts in clotting markers | adults seeking circulation/clotting-marker support | Hours to weeks |
atherosclerosis markers Limited Evidence | Modest | adults with subclinical atherosclerosis | Months |
blood pressure reduction
- Effect
- Modest, ~a few mmHg systolic
- Best fit
- adults with mildly elevated blood pressure
- Time
- Weeks
fibrinolytic / circulation support
- Effect
- Measurable shifts in clotting markers
- Best fit
- adults seeking circulation/clotting-marker support
- Time
- Hours to weeks
atherosclerosis markers
- Effect
- Modest
- Best fit
- adults with subclinical atherosclerosis
- Time
- Months
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
blood pressure reduction
Biomarker supportRandomized trials and pooled analyses show nattokinase modestly lowers systolic (and sometimes diastolic) blood pressure, possibly via effects on the renin-angiotensin system. Blood pressure is an intermediate marker here; trials are modest in size and duration.
Bottom line: Can modestly lower blood pressure as a marker; not a substitute for established antihypertensives.
fibrinolytic / circulation support
Biomarker supportOral nattokinase is absorbed in active amounts and lowers fibrinogen and prothrombotic markers such as PAI-1 while enhancing fibrinolysis in small trials. These are coagulation-marker changes; clinical thrombosis outcomes have not been established.
Bottom line: Shifts clotting markers toward fibrinolysis, but clinical benefit is unproven.
atherosclerosis markers
Biomarker supportA small trial reported reduced carotid plaque size and improved lipids with nattokinase over time. This is a single small study of imaging/lipid markers and needs replication.
Bottom line: Early marker data on plaque are intriguing but unconfirmed.
How it works
How to take it
What to track
2 commercial forms
Compare the main delivery options and what they’re best suited for.
Standardized nattokinase (NSK-SD)
The form used in most published clinical trials. Vitamin K2 is removed to avoid antagonizing the fibrinolytic effect.
Most clinical research uses this branded form, which guarantees vitamin K2 removal and consistent fibrinolytic activity.
Generic nattokinase
Less standardized; quality varies by manufacturer.
Activity varies; check fibrinolytic units (FU) per serving.
Safety
Know the common side effects, key cautions, and who should avoid it.
Common side effects
Serious risks
increased bleeding risk, especially with anticoagulants or antiplatelets
rare allergic reactions (notably in soy allergy)
Who should avoid it
- active bleeding or bleeding disorders
- anyone within 2 weeks of surgery
- soy allergy
- pregnancy and breastfeeding
Pregnancy & breastfeeding
Avoid in pregnancy and lactation due to insufficient safety data and bleeding concerns.
Interactions
additive fibrinolytic/anticoagulant effect raises bleeding risk
additive bleeding risk
may further increase bleeding risk
possible additive blood-pressure lowering
Food sources
| Food | Amount | %DV |
|---|---|---|
| Natto (fermented soybeans, 1/2 cup) | Naturally rich in nattokinase | — |
Natto (fermented soybeans, 1/2 cup)
- Amount
- Naturally rich in nattokinase
- %DV
- —
Choosing a product
What to look for on the label — and what to be skeptical of.
Look for…
Be skeptical of…
Frequently asked questions
Is nattokinase the same as natto?⌄
Natto is the fermented soybean food. Nattokinase is the specific fibrinolytic enzyme isolated from natto. Eating natto provides nattokinase plus other nutrients (including vitamin K2).
Can nattokinase replace blood thinners?⌄
No. Nattokinase has modest fibrinolytic effects but is not a substitute for prescription anticoagulants in conditions requiring strong clot prevention (atrial fibrillation, prior DVT, mechanical heart valves).
Will nattokinase lower my blood pressure?⌄
Studies show modest reductions in systolic blood pressure (4-10 mmHg). Useful as an adjunct for borderline hypertension but not a substitute for prescription antihypertensives in significant hypertension.
Is nattokinase safe with blood thinners?⌄
Combining significantly raises bleeding risk. Do not combine without your prescriber's explicit guidance and monitoring.
Should I stop before surgery?⌄
Yes. Stop at least 2 weeks before any planned surgery, dental procedure, or anything that could bleed. Resume after as directed by your surgeon.
References by claim
Track Nattokinase with Pilora
Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.
Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.