What is Nattokinase?
Nattokinase is a proteolytic enzyme derived from natto, a traditional Japanese fermented soybean dish. This enzyme is produced by the bacterium Bacillus subtilis var. natto during the fermentation process. Discovered in 1987 by Japanese researcher Dr. Hiroyuki Sumi, nattokinase has gained attention for its potential cardiovascular benefits, particularly its ability to break down fibrin, a protein involved in blood clot formation.
As a supplement, nattokinase is extracted and purified from natto and is typically measured in fibrinolytic units (FU), which indicate the enzyme’s clot-dissolving activity. Unlike many other enzymes that are destroyed by stomach acid, nattokinase remains active in the digestive system and can be absorbed into the bloodstream.
Health benefits & uses
Cardiovascular health (Moderate evidence): Several studies suggest nattokinase may help support cardiovascular health by improving blood flow and reducing blood viscosity. A randomized controlled trial published in Hypertension Research found that nattokinase supplementation helped reduce blood pressure in hypertensive patients over 8 weeks.
Fibrinolytic activity (Moderate evidence): Research indicates nattokinase can enhance the body’s natural ability to dissolve blood clots. Studies show it can break down fibrin both directly and by activating the body’s own fibrinolytic enzymes, though most research has been conducted in laboratory settings or small human trials.
Blood pressure support (Limited evidence): Some clinical studies suggest nattokinase may help maintain healthy blood pressure levels, though more large-scale research is needed to establish definitive benefits.
Circulation improvement (Limited evidence): Preliminary research indicates nattokinase might help improve overall circulation and reduce markers of cardiovascular risk, but evidence remains limited to small studies.
How it works
Nattokinase functions primarily as a fibrinolytic enzyme, meaning it breaks down fibrin, the protein that forms the structural framework of blood clots. The enzyme works through multiple mechanisms:
It directly cleaves fibrin into smaller, soluble fragments that can be easily removed from the bloodstream. Additionally, nattokinase activates tissue plasminogen activator (tPA) and urokinase, the body’s natural clot-dissolving enzymes. The enzyme also helps break down plasminogen activator inhibitor-1 (PAI-1), a protein that normally inhibits the body’s fibrinolytic system.
These combined actions may help maintain healthy blood flow and reduce the risk of excessive clot formation. The enzyme’s activity appears to last for several hours after ingestion, providing sustained fibrinolytic effects.
Dosage
Typical adult dosages range from 1,000 to 4,000 FU (fibrinolytic units) daily, usually taken on an empty stomach for optimal absorption. Most studies have used doses between 2,000-3,000 FU per day. There is no established RDA (Recommended Daily Allowance) or UL (Upper Limit) for nattokinase as it is not considered an essential nutrient.
Common dosing schedules include:
- 1,000-2,000 FU once daily for general cardiovascular support
- 2,000-4,000 FU daily, divided into two doses, for more intensive support
Healthcare provider guidance is essential before starting supplementation, especially for individuals taking blood-thinning medications or those with bleeding disorders.
Food sources
Natto is the primary and virtually only natural food source of nattokinase. This traditional Japanese food is made by fermenting soybeans with Bacillus subtilis var. natto. Natto has a distinctive smell, slimy texture, and strong flavor that can be challenging for those unaccustomed to it.
One serving (approximately 100 grams) of natto typically contains 1,000-2,000 FU of nattokinase activity. However, the enzyme content can vary depending on the fermentation conditions and bacterial strain used. Natto is commonly available in Japanese grocery stores and some health food stores, usually sold frozen or refrigerated.
Other fermented soy products do not contain significant amounts of nattokinase, as this specific enzyme is produced only by the particular strain of bacteria used in natto production.
Safety & side effects
Nattokinase is generally well-tolerated by most healthy adults when used appropriately. However, some individuals may experience mild side effects including digestive upset, nausea, or headache.
The primary safety concern relates to nattokinase’s blood-thinning effects. Excessive bleeding or bruising may occur, particularly in individuals taking anticoagulant medications or those with bleeding disorders. Some users report a slight increase in bleeding time even at standard doses.
Allergic reactions are possible, especially in individuals with soy allergies, though the purification process typically removes most allergenic soy proteins. Quality control is important, as some supplements may contain vitamin K2, which can interfere with blood-thinning medications.
Interactions
Drug interactions: Nattokinase may significantly enhance the effects of anticoagulant and antiplatelet medications, including warfarin, heparin, aspirin, and clopidogrel. This combination can increase bleeding risk and requires careful medical supervision.
NSAIDs (non-steroidal anti-inflammatory drugs) may also interact with nattokinase, potentially increasing bleeding risk. Blood pressure medications might have enhanced effects when combined with nattokinase.
Supplement interactions: Other blood-thinning supplements such as garlic, ginkgo biloba, fish oil (in high doses), and vitamin E may have additive effects with nattokinase. Vitamin K supplements may counteract nattokinase’s effects on blood clotting.
Who should be cautious
Individuals taking any blood-thinning medications should avoid nattokinase unless under direct medical supervision. Those with bleeding disorders, including hemophilia or von Willebrand disease, should not use nattokinase.
People scheduled for surgery should discontinue nattokinase at least two weeks prior to the procedure due to increased bleeding risk. Individuals with active peptic ulcers, recent stroke, or any condition involving bleeding should avoid this supplement.
Pregnant and breastfeeding women should not use nattokinase due to insufficient safety data. People with low blood pressure should use caution, as nattokinase may further reduce blood pressure levels.
Frequently asked questions
Can I take nattokinase with blood pressure medications?
Nattokinase may enhance the effects of blood pressure medications, potentially causing blood pressure to drop too low. Consult your healthcare provider before combining these, as medication adjustments may be necessary.
How long does it take to see benefits from nattokinase?
Some studies suggest fibrinolytic activity increases within 2-8 hours of taking nattokinase, but cardiovascular benefits may take several weeks to months of consistent use to become apparent.
Is nattokinase better than aspirin for blood thinning?
Nattokinase and aspirin work through different mechanisms and should not be considered interchangeable. Aspirin is a proven medication for cardiovascular protection, while nattokinase requires more research. Never replace prescribed medications with supplements without medical supervision.
Can vegetarians and vegans take nattokinase?
Yes, nattokinase is derived from fermented soybeans and is suitable for vegetarians and vegans. However, check supplement labels for any non-vegetarian capsule materials or additives.
Does nattokinase need to be taken on an empty stomach?
Yes, nattokinase is best absorbed when taken on an empty stomach, typically 1-2 hours before meals or 2 hours after eating. Taking it with food may reduce its effectiveness.
Classification:
Typical dose: — · Studied up to: —
References
Authoritative profile & live regulatory status: Nattokinase on SupplementIndex →