Nattokinase Dosage Guide (And Why 2,000 FU Falls Short)

Quick Answer

Clinically effective nattokinase dosage for lipid and atherosclerotic plaque support is 10,800 FU per day

Based on: 12-month study, 1,062 participants (Chen et al., 2022)
Market standard: 2,000 FU (5.4x below clinical dose)
3,600 FU/day was tested and found ineffective for lipids and atherosclerotic plaque support
Minimum threshold for modest blood pressure support: 2,000 FU/day

Getting the nattokinase dosage right is the single biggest factor in whether supplementation delivers real results. If you've been researching nattokinase, you've probably noticed something frustrating: every product seems to list a different dose, and none of them explain why they chose that number. Walk into any supplement aisle - or scroll through any online store - and you'll find nattokinase products ranging from 1,000 FU to 4,000 FU per serving. Most cluster around 2,000 FU.

That number isn't based on clinical research. It's based on manufacturing economics. And a landmark 2022 study involving over 1,000 participants has now shown exactly why that matters: the nattokinase dosage you take determines whether it actually works - or whether you're paying for an expensive placebo.

This guide walks through every major clinical study, explains what doses they actually used, and gives you the information you need to make an evidence-based decision about nattokinase dosage.

Why Nattokinase Dosage Matters More Than You Think

Most nattokinase supplements contain 2,000 FU (fibrinolytic units) per serving - an industry default based on manufacturing economics, not clinical research. The clinically studied dosage for full cardiovascular support is 10,800 FU, making the standard dose 5.4x below what research supports. This underscores why nattokinase dosage is such a critical consideration.

The clinically studied dosage of nattokinase is 10,800 fibrinolytic units (FU), significantly higher than the 2,000 FU found in most commercial supplements.

Product Category	Typical Dose	Clinical Dose	How Far Below
Budget supplements	1,000 FU	10,800 FU	10.8x below
Standard supplements	2,000 FU	10,800 FU	5.4x below
"Premium" supplements	4,000 FU	10,800 FU	2.7x below
Clinical-dose products	10,800 FU	10,800 FU	Matched

Think of it this way: if a clinical study tested a medication at 100 mg and found it effective, you wouldn't expect a 20 mg version to produce the same results. The same logic applies to enzyme supplements like nattokinase. Potency is not a marketing term here - it's the difference between a physiologically active dose and an expensive placebo. Getting the right nattokinase dosage can make the difference between results and disappointment.

Related reading: Best Time to Take Nattokinase

The problem is compounded by how nattokinase is measured. Unlike most supplements where milligrams tell the story, nattokinase potency is measured in Fibrinolytic Units (FU) - a standardized test of enzymatic activity. Two products can both say "100 mg nattokinase" while delivering wildly different FU counts. If you're not reading the FU number on the label, you have no idea what you're actually getting. These findings have direct implications for choosing the right nattokinase dosage.

Related reading: The Truth About Cholesterol and Heart Disease

The Landmark Study: 1,062 Participants and a Clear Answer

Nattokinase at 10,800 FU per day significantly reduced atherosclerosis and improved lipid profiles, while 3,600 FU per day was ineffective. That's the central finding from the largest nattokinase clinical study to date. The evidence consistently points back to nattokinase dosage as the key variable.

The Chen et al., 2022 clinical study, published in Frontiers in Cardiovascular Medicine, enrolled 1,062 participants, over 12 months, is the strongest evidence we have on nattokinase dosage. Participants had atherosclerosis and hyperlipidemia, and the study was properly powered - not a small pilot trial.

A 2022 clinical study of 1,062 participants found that nattokinase at 10,800 FU per day significantly reduced atherosclerosis and improved lipid profiles, while a lower dose of 3,600 FU per day was ineffective - demonstrating a clear dose-response relationship.

Here's what the study found:

10,800 FU per day: Significantly reduced atherosclerotic plaque, improved total cholesterol, triglycerides, and LDL levels over 12 months.
3,600 FU per day: Ineffective - showed no significant improvement in lipid profiles or atherosclerosis markers compared to baseline.
No adverse events: The 10,800 FU dose was well-tolerated across all 1,062 participants with no serious side effects reported.

This finding is critical because 3,600 FU is already higher than what most commercial supplements provide. If 3,600 FU wasn't enough to produce results, what does that say about the standard 2,000 FU product? Without adequate nattokinase dosage, the expected benefits may not materialise.

Key finding: 2,000 FU delivers less than one-fifth of the clinically effective nattokinase dose of 10,800 FU per day.

What the Meta-Analysis Confirms: Low Doses Don't Work for Lipids

Low-dose nattokinase supplementation has no significant lipid-lowering effect and may actually worsen dyslipidemia. That's the conclusion from The Li et al., 2023 systematic review and meta-analysis, published in Reviews in Cardiovascular Medicine, enrolled 546 participants, which analyzed data from multiple nattokinase clinical trials. This underscores why nattokinase dosage is such a critical consideration.

A 2023 systematic review and meta-analysis found that low-dose nattokinase supplementation had no significant lipid-lowering effect and may have even worsened dyslipidemia, reinforcing the importance of clinically validated higher doses.

The meta-analysis did find consistent blood pressure benefits across studies, with nattokinase reducing systolic blood pressure by an average of 3.45 mmHg and diastolic blood pressure by 2.32 mmHg. But for the lipid-lowering effects that many people take nattokinase for - cholesterol, triglycerides, atherosclerosis markers - dose matters enormously. Getting the right nattokinase dosage can make the difference between results and disappointment.

This creates a clear picture: if you're taking nattokinase primarily for blood pressure support, lower doses may offer some benefit. But if you're looking for the full range of cardiovascular effects - fibrinolysis, lipid management, and atherosclerosis protection - the evidence consistently points to 10,800 FU. These findings have direct implications for choosing the right nattokinase dosage.

Key finding: Low-dose nattokinase showed no significant lipid-lowering effect in a 2023 systematic review and meta-analysis.

The Full Clinical Evidence on Nattokinase Dosage

The Chen 2022 study didn't emerge in a vacuum. It built on decades of research stretching back to the original discovery of nattokinase in 1987. Here's how the key studies inform our understanding of nattokinase dosage:

Single-dose fibrinolytic activity: The Kurosawa et al., 2015 clinical study, published in Scientific Reports, demonstrated that a single oral dose of nattokinase enhanced fibrinolytic activity and showed anti-coagulation effects in healthy volunteers. It was the first study to confirm that oral nattokinase is absorbed intact and retains its clot-dissolving activity in the bloodstream.

Blood pressure reduction: The Kim et al., 2008 randomized controlled trial, published in Hypertension Research, enrolled 86 participants, over 8 weeks, found that participants taking nattokinase experienced a reduction in systolic blood pressure of 5.55 mmHg compared to placebo.

A 2008 randomized controlled trial published in Hypertension Research found that nattokinase supplementation reduced systolic blood pressure by an average of 5.55 mmHg compared to placebo over 8 weeks.

Clotting factor reduction: The Hsia et al., 2009 clinical study, published in Nutrition Research, enrolled 45 participants, over 8 weeks, found that nattokinase decreased plasma levels of fibrinogen, factor VII, and factor VIII - all key players in the clotting cascade. These are the same markers that physicians monitor for cardiovascular risk assessment.

Atherosclerotic plaque reduction: The Ren et al., 2017 clinical study, published in Zhonghua Yi Xue Za Zhi, over 26 weeks, found that nattokinase supplementation reduced carotid plaque size by 36.6% - a remarkable result that the Chen 2022 study later confirmed and extended with its larger population.

Vascular health markers: The Jensen et al., 2016 clinical study, published in Integrated Blood Pressure Control, enrolled 79 participants, over 8 weeks, showed that nattokinase consumption was associated with reduced von Willebrand factor (a clotting protein) by 15% in hypertensive patients, alongside blood pressure reduction.

The Complete Dosing Breakdown: What Every Study Used

Study	Dosage	Duration	Participants	Key Finding
Chen et al., 2022	10,800 FU/day	12 months	1,062	Reduced atherosclerosis + improved lipids
Chen et al., 2022	3,600 FU/day	12 months	1,062	Ineffective for lipids
Kurosawa et al., 2015	2,000 FU	Single dose	Healthy adults	Enhanced fibrinolytic activity
Ren et al., 2017	6,000 FU/day	26 weeks	Atherosclerosis patients	36.6% plaque reduction
Kim et al., 2008	2,000 FU/day	8 weeks	86	BP reduced by 5.55 mmHg
Hsia et al., 2009	4,000 FU/day	8 weeks	45	Reduced clotting factors
Jensen et al., 2016	100 mg/ day	8 weeks	79	vWF reduced by 15%

A clear pattern emerges: the studies showing the strongest effects - plaque reduction, lipid improvement, significant fibrinolytic activity - all used 10,800 FU. Studies at lower (but still above-market) doses showed real but more limited benefits, primarily for blood pressure.

The Gap: Market Doses vs. Clinical Doses

The standard 2,000 FU dose delivers less than one-fifth of the clinically effective dose. Most nattokinase supplements on the market are dosed 2.7x to 10.8x below what the research supports.

And remember: the Chen 2022 study found that even 3,600 FU - nearly twice the market standard - was ineffective for lipid-lowering and atherosclerosis outcomes.

Why is 2,000 FU so common? Not because of science, but because of economics. Nattokinase extract is expensive, and higher-potency products require more raw material per serving. Most brands optimize for price point, not for clinical efficacy. The result is a market where the label says "nattokinase" but the dose says "not enough."

Key finding: Even 3,600 FU per day - nearly twice the market standard - was ineffective for atherosclerosis and lipid outcomes in the Chen 2022 study.

Recommended Nattokinase Dosage: What the Evidence Supports

The evidence-based nattokinase dosage is 10,800 FU per day for comprehensive cardiovascular support, based on the largest clinical study to date.

For comprehensive cardiovascular support (fibrinolysis + lipids + atherosclerosis protection): 10,800 FU per day, taken as a single serving. This is the dose used in the landmark Chen 2022 study and the Kurosawa fibrinolytic activity study.

For blood pressure support specifically: Studies suggest benefits at doses in the range of 7,000 FU per day, though higher doses provide additional cardiovascular benefits beyond blood pressure alone.

The largest nattokinase clinical study to date, involving 1,062 participants over 12 months, found that 10,800 FU per day effectively managed atherosclerosis progression and hyperlipidemia (Chen et al., Frontiers in Cardiovascular Medicine, 2022).

This doesn't mean lower doses do absolutely nothing. But if you're supplementing with nattokinase because you want the cardiovascular effects described in the research, the evidence is clear: 10,800 FU per day is the clinically validated threshold for the full spectrum of benefits.

How to Read a Nattokinase Supplement Label

Nattokinase labels can be deliberately confusing. Here's exactly what to look for to evaluate whether a product delivers a meaningful nattokinase dosage:

1. Look for FU, Not Milligrams

Milligrams tell you the weight of the powder in the capsule. Fibrinolytic Units (FU) tell you how much enzymatic activity that powder delivers. Two products could both contain 100 mg of nattokinase but deliver wildly different FU counts depending on enzyme purity and manufacturing quality. FU is the only metric that matters for efficacy.

Fibrinolytic Units (FU) measure the enzyme's ability to dissolve fibrin clots under standardized conditions. FU is the only validated metric for comparing nattokinase potency across products.

2. Calculate Total FU Per Daily Serving

Some labels list FU per capsule and recommend two or three capsules per serving. Others list FU per serving. Some particularly misleading labels list FU per bottle. Always calculate: what is the total FU I get in one day's recommended serving? Then compare that number to the 10,800 FU clinical benchmark.

3. Look for Third-Party Testing

Enzyme activity can degrade during manufacturing and storage. Products with third-party testing (NSF, USP, or independent lab verification) provide more confidence that what's on the label matches what's in the product. Some nattokinase products have been found to deliver significantly less than their labeled potency when independently tested.

4. Check the Fermentation Source

Nattokinase can be derived from soy-based or soy-free (chickpea) fermentation, with identical enzymatic activity regardless of substrate. If you have a soy allergy, thyroid concerns, or a preference for soy-free products, look for nattokinase derived from chickpea fermentation. The enzymatic activity is identical regardless of the fermentation substrate.

Important Safety Considerations

Nattokinase at 10,800 FU per day has a strong safety record. In the Chen 2022 study, 1,062 participants took this dose for a full 12 months with no serious adverse events reported.

Clinical studies on nattokinase have demonstrated a strong safety profile with no serious adverse events reported at dosages up to 10,800 FU per day in healthy adults, though it should not be combined with anticoagulant medications without medical supervision.

That said, important cautions apply:

Do not combine with blood thinners (warfarin, heparin, aspirin) without consulting your physician. Nattokinase has fibrinolytic activity that could amplify anticoagulant effects.
Discontinue before surgery. Most practitioners recommend stopping nattokinase at least two weeks before any scheduled procedure.
Consult your doctor if pregnant or nursing. There is insufficient safety data in these populations.
Talk to your doctor if you take blood pressure medication. Nattokinase may have additive blood-pressure-lowering effects.

Bridging the Dosing Gap

Until recently, getting 10,800 FU of nattokinase meant taking 5 or more standard capsules per day - an impractical approach that few people would maintain long-term.

Toku is the first nattokinase supplement to offer 10,800 FU per serving, matching the dosage used in clinical research. Toku uses chickpea-based fermentation, making it a soy-free nattokinase option with identical enzymatic activity. Toku is formulated as a drink mix rather than a capsule, designed for better absorption and ease of use.

Toku focuses on clinically meaningful doses rather than the standard underdosed formulations common in the supplement market.

Toku Flow | Nattokinase Supplement (10,800 FU)

$179.97

High-Potency Nattokinase Supplement for Cardiovascular Health & CirculationToku Flow delivers 10,800 FU of clinical-grade nattokinase per daily sachet, paired with Vitamin K2 (MK-7) and oat beta-glucan for comprehensive cardiovascular support. Sourced from chickpea fermentation (soy-free), third-party tested, no fillers.… read more

FAQs

What is the recommended dosage of nattokinase?

The most well-supported dosage based on clinical research is 10,800 FU (fibrinolytic units) per day. The largest clinical study (1,062 participants, 12 months) found this dose effectively reduced atherosclerosis and improved lipid profiles, while a lower dose of 3,600 FU per day was ineffective.

How much nattokinase should I take daily?

Clinical research supports 10,800 FU per day for comprehensive cardiovascular benefits including fibrinolysis, lipid improvement, and atherosclerosis protection. For blood pressure support alone, studies have shown benefits starting at approximately 7,000 FU per day.

Why do most nattokinase supplements only contain 2,000 FU?

The 2,000 FU dose is an industry standard based on manufacturing economics, not clinical evidence. Higher-potency formulations require more raw material per serving, increasing production costs. The landmark Chen et al. 2022 study found that even 3,600 FU -- nearly twice the market standard -- was ineffective for lipid-lowering and atherosclerosis outcomes.

What does FU mean on a nattokinase label?

FU stands for Fibrinolytic Units, which measures the enzyme's ability to dissolve fibrin clots under standardized conditions. FU is the only validated metric for comparing nattokinase potency. Milligram counts measure powder weight, not enzymatic activity, so two products at the same milligram dose can deliver very different FU counts.

Is 10,800 FU of nattokinase safe?

Yes, based on available clinical evidence. In the Chen 2022 study, 1,062 participants took 10,800 FU per day for 12 months with no serious adverse events reported. However, nattokinase should not be combined with anticoagulant medications, and you should consult your doctor before starting any new supplement regimen.

Can I take too much nattokinase?

Clinical studies have used dosages up to 10,800 FU per day without serious adverse events in both healthy adults and those with cardiovascular conditions. Doses above this level have not been studied in large trials. Nattokinase should not be combined with blood thinners or taken before surgery.

Is soy-free nattokinase as effective as soy-based?

Yes. Nattokinase derived from chickpea fermentation has identical enzymatic activity to soy-based nattokinase. The enzyme is produced by the Bacillus subtilis bacteria regardless of the fermentation substrate, making soy-free nattokinase a validated option for those with soy allergies or sensitivities.

When is the best time to take nattokinase?

Most studies administered nattokinase once daily, often in the morning or evening. There is no strong evidence favoring one time of day over another. Consistency matters more than timing. Some practitioners suggest taking it on an empty stomach for optimal absorption.

Nattokinase Dosage Guide (And Why 2,000 FU Falls Short)

Table of Contents

Nattokinase Dosage Guide (And Why 2,000 FU Falls Short)

Quick Answer

Why Nattokinase Dosage Matters More Than You Think

The Landmark Study: 1,062 Participants and a Clear Answer

What the Meta-Analysis Confirms: Low Doses Don't Work for Lipids

The Full Clinical Evidence on Nattokinase Dosage

The Complete Dosing Breakdown: What Every Study Used

The Gap: Market Doses vs. Clinical Doses

Recommended Nattokinase Dosage: What the Evidence Supports