Nattokinase: benefits, side effects and usage of the enzyme

Nattokinase is an enzyme that owes its name to the traditional Japanese dish Natto. This sticky, stringy delicacy is made by boiling and then fermenting soybeans. Bacillus subtilus (Japanese: Nattokin) is used as a starter culture in this refinement process, which naturally produces higher amounts of nattokinase. As a result, nattokinase and other enzymes accumulate in natto during the fermentation process.

Nattokinase was first described in 1987 by the Japanese researcher Hiroyuki Sumi. Due to its relatively ‘young age’, nattokinase research is still in its infancy in some areas. To save you a lot of research work, we have familiarised ourselves with the subject matter for you and summarised the most well-researched benefits and effects of nattokinase below:

1) Nattokinase improves blood flow. Nattokinase is often referred to as a ‘natural blood thinner’. This effect is due to its ability to break down fibrin, a protein that forms during blood clotting. This enables nattokinase not only to counteract the formation of blood clots, but also to dissolve smaller blood clots that have already formed – an important protective mechanism against cardiovascular diseases caused by blood clots (e.g. heart attacks, strokes).

Several studies, including a clinical study on 45 people, confirm that nattokinase has an influence on blood clotting not only in theory but also in practice. Supplementing with 4000 FU units of nattokinase per day for eight weeks reduced several blood clotting factors. This effect was independent of whether the subjects were healthy, suffered from cardiovascular diseases or were on dialysis. Nattokinase is therefore suitable for reducing blood clotting in various life situations.

2) Nattokinase lowers blood pressure. High blood pressure is usually the first sign of cardiovascular disease. In the long term, this vascular hyperpressure can lead to a vicious circle, as it can also cause vascular damage.

A clinical study on 86 people showed that nattokinase can not only improve blood flow but also lower blood pressure naturally. In this study, an 8-week intake of 2000 FU units of nattokinase per day reduced both systolic (-9.1 %) and diastolic blood pressure (- 6 %).

Chronic inflammation is the underlying cause of a variety of diseases. This also applies, among other things, to arteriosclerosis (= vascular calcification), in which chronic inflammatory processes occur in the vessel walls. Based on this background, researchers wondered whether and how Nattokinase can influence inflammatory processes. It was shown both in cell experiments in the laboratory and in a living model (in vivo – in a living organism) that the enzyme can inhibit certain inflammatory processes and regulate an overactivation of the immune system (the macropages).

Other studies that had focused on inflammations of the digestive system or nervous system were also able to confirm an anti-inflammatory effect of the enzyme. Nevertheless, human studies are still needed for a well-founded conclusion. It will be interesting to see what further research has to offer in this area!

Nattokinase is generally considered to be a natural substance with few side effects. However, people who are already taking blood-thinning medication should not use nattokinase without medical advice and supervision, as this can increase the effect of the blood-thinning medication and cause unwanted side effects.

Also before surgery, including dental surgery, nattokinase should be discontinued at least one week in advance to avoid excessive bleeding during the operation.

Nattokinase used on its own is considered safe. This was also confirmed in a toxicological study from 2016, in which the tolerated dose in healthy people was even significantly higher than the currently recommended dose.

Nattokinase is mainly found in the traditional Japanese dish natto. The enzyme is practically absent from our common foods.

When taking nattokinase, you should ideally follow the manufacturer's recommended dosage – unless your doctor or therapist recommends otherwise.

Nattokinase is best consumed with plenty of fluids. For optimal tolerability, it is recommended to take it with a meal.

Nattokinase can be taken at any time of day, so you can integrate the enzyme into your daily routine in a way that suits you best.

When taking nattokinase, it is best to follow the manufacturer's recommendation. In most cases, they recommend 2.000 FU daily – a dosage that studies show is effective. However, this recommendation does NOT apply to people who take blood thinners or those who want a dosage tailored to their needs. These people should seek individualised advice from their doctor and, if necessary, determine the appropriate dosage with the help of medical expertise.

Those who take nattokinase for blood clotting can expect to see an effect relatively quickly: nattokinase begins to affect blood clotting just 2 hours after ingestion, reaching its peak after about 4 hours and starting to wear off after about 8 hours. People who want to take nattokinase for its other properties (e.g. to lower blood pressure naturally) need to be more patient and take the enzyme over a longer period of time to see results.

Nattokinase should be taken regularly. Otherwise, its effect will quickly wear off.

While natto is consumed regularly in Japan, there are no studies on the safety of taking nattokinase for more than 12 months.

Nattokinase is available to buy in a variety of forms. It is most commonly found in capsules. Tablets or powder are much less common.

Nattokinase capsules have two potential advantages over tablet variants: on the one hand, the use of capsules makes it possible to avoid unnecessary additives, while on the other hand, the use of capsules makes it possible to use gastric acid-resistant capsules to protect the nattokinase. This ensures that optimal amounts of active nattokinase reach the intestine – an advantage that also applies to powder preparations.

If you still want to take nattokinase in powder form, you should make sure that the product is as free as possible from additives and ideally comes in pre-portioned doses. This not only ensures precise dosing, but is also more hygienic.

A nattokinase product can only be as good as the raw material used to produce it. The manufacture of nattokinase requires a complex and delicate fermentation process in which the enzyme is produced by microorganisms. In this case, the use of a branded raw material is particularly suitable to ensure consistently high quality.

The brand raw material NSK-SD® is the pioneer in the field of nattokinase and is obtained by the traditional method of soybean fermentation. This guarantees that NSK-SD® corresponds to the original nattokinase that has been consumed in Japan for thousands of years. Furthermore, NSK-SD® is the first officially approved nattokinase raw material. Accordingly, numerous clinical studies are available that document the effectiveness and safety of NSK-SD®.

FU (Fibrinolytic Unit) is a unit that reflects how effectively an enzyme can break down fibrin. The higher the value, the higher the enzyme activity and thus the ability to break down fibrin.

As mentioned above, people taking blood thinners should never take nattokinase on their own initiative, as this combination can lead to undesirably strong blood thinning. If you are considering taking both, you should definitely seek medical advice. Experienced physicians can provide individualised advice and, if necessary, adjust the dosage of the medication and nattokinase to match. However, they should only be taken together under strict, close monitoring of blood clotting.

Nattokinase and vitamin K2 (as MK-7) are found together in natto. Both natural substances have different effects on blood clotting: while nattokinase prevents blood clotting, vitamin K2 supports it. However, these different effects do not generally preclude their joint intake. This is because our coagulation factors only allow blood to clot when needed and do not ‘force’ it to do so.

The situation is different for people who use anticoagulants. Since both nattokinase and vitamin K2 can affect the way the medication works, medical advice is essential.

A combination of nattokinase and oligomeric proanthocyanidins (OPC) is definitely a smart move. After all, both natural substances are beneficial for our cardiovascular system: while nattokinase improves our blood flow, lowers our blood pressure and possibly reduces inflammation in the blood vessels (more research is needed here), OPCs maintain the elasticity of the blood vessel walls and protect them from oxidative damage.

Ginkgo biloba and nattokinase are two natural substances that both have an effect on the cardiovascular system. Since their joint use has not yet been researched in detail, the combination should not be taken without consulting a doctor.

Conclusion: An insider tip in Japan for a long time, nattokinase is now also conquering the Western world. And the enzyme is very useful here! Due to its proven effects on cardiovascular health and its possible anti-inflammatory effect, nattokinase can make an important contribution to healthy aging.