Nattokinase—The Natural Blood Thinner

How important is healthy blood circulation to you?Blood Flow

The significance of proper blood circulation can not be over emphasized. The ability of your heart to pump blood throughout your body efficiently and effectively is the cornerstone of good health.

Unfortunately, there are forces at work that interfere with your heart’s ability to effectively move blood through your veins and arteries. Some of these forces are natural extensions of the aging process. Others are genetic predispositions that have been passed down through generations. And, of course, others are risk factors that we created through our own unhealthy habits that leave us susceptible to cardiovascular disease (CVD).

Whatever the reason, mainstream healthcare has banded together with the pharmaceutical industry to offer a temporary quick fix for CVD, today’s number one killer. They have developed statin drugs to reduce cholesterol. They promote aspirin and warfarin to thin the blood. They provide anti-hypertension medications to reduce blood pressure and offer bypass surgery and angioplasty to clear the arteries. Essentially, these all help prolong the life of a patient with cardiovascular disease. But none of these drugs or procedures is without risk or side effects. So what do we do?

You can greatly reduce the risk of cardiovascular disease by modifying your lifestyle and adding nutritional supplements proven to support cardiovascular health. Research has shown that oral EDTA chelation is extremely effective in removing toxic heavy metals from the blood stream. And there are new studies showing that vitamin K2 can prevent arterial calcification. And of course, eating a lighter, more balanced diet, quitting tobacco and exercising regularly will go a long way towards heading off most cases of heart disease and stroke before they ever happen.

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But, can you do more? Yes, there is something else you can do to ensure your circulatory system is operating optimally. But before we get to that, we’d like to first mention …

A word about blood clots

Blood clotting is a natural process that allows our blood to thicken and form a clot or thrombus of blood cells. When a blood vessel is injured, platelets clump together and strands of the blood protein fibrin glue them together in order to stop the bleeding. Eventually the clot helps form a protective scab over a healing wound. If our bodies did not have the ability to clot blood, we would bleed to death after even a minor cut, which was often the case with hemophiliacs before the development of pharmaceutical blood clotting agents.

But sometimes blood clots form even when you have not been wounded or cut. Although most blood clots naturally dissolve on their own without complications, there are two situations in which they can wreak havoc before they are reabsorbed by your body.

1) A thrombus (blood clot) can form in an artery and block the flow of blood which cuts off oxygen supply. This can trigger a heart attack and result in damage, destruction (infarction), or even death of the tissues (necrosis) in the heart. In the brain, blood clots also block blood and oxygen from reaching necessary areas, which can result in senility and/or stroke.1

2) A piece of the blood clot could form in one of the heart’s chambers and then travel through the bloodstream, lodging in either an organ or an artery and cutting off the blood supply from that point, causing an embolism. An embolism is especially dangerous when it ends up in your lung, as it can result in a sudden lack of respiratory function.

The most common cause of these emboli is blood clots that form during atrial fibrillation. This is a disorder found in about 2 million Americans. In atrial fibrillation the heart’s two small upper chambers (the atria) quiver instead of beating effectively. Some blood isn’t pumped completely out of them when the heart beats, so it pools and clots. When a blood clot enters the circulation and lodges in a narrowed artery of the brain, a stroke occurs.

The chances of developing thrombi increase as we age

Although our human body produces several enzymes for making blood clots, it produces only one enzyme—plasmin—for dissolving them. The problem is, as we age the production of plasmin is reduced, making blood more prone to coagulation and clotting.

To make matters worse, fibrinogen (a blood clotting protein) levels rise as we get older.2 And high levels of fibrinogen usually lead to increased platelet aggregation, blood clots, and eventually heart attack or stroke. In fact, high fibrinogen levels are considered a more dangerous risk factor for heart attack and stroke than high cholesterol. A study of 2,116 men found that those with high LDL (bad) cholesterol but low fibrinogen levels had only one sixth the risk for heart attack than the men with low LDL and high fibrinogen.3

So preventing blood clots, particularly in older individuals, is a crucial step in preventing heart attack and stroke. And if you can do this naturally, without expensive pharmaceuticals and their nasty side effects, why not start now?

Nattokinase – the natural blood thinner

Natural nutritional support for normal, healthy blood flow and circulation can be found in the enzyme Nattokinase. Nattokinase has been shown to support normal blood pressure, dissolve blood clots and prevent them from forming in the first place!

What is Nattokinase?

Nattokinase is a potent fibrinolytic (anti-clotting) enzyme extracted and highly purified from a traditional Japanese food called Natto. Natto is a fermented cheese-like food that has been used in Japanese culture for more than 1,000 years and as a folk remedy for heart and vascular diseases. Research has shown that Nattokinase supports the body’s ability to break up and dissolve the unhealthy coagulation of blood. In fact, it has been shown to have four times greater fibrinolytic activity than plasmin—the body’s primary anti-clotting enzyme.4

How is Nattokinase made?

Natto is produced in a fermentation process by adding the bacteria Bacillus subtilis to boiled soybeans. The resulting Nattokinase enzyme is produced when Bacillus subtilis acts on the soybeans. While other soy foods contain enzymes, it is only the Natto preparation that contains the specific Nattokinase enzyme.

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How was Nattokinase discovered?

Japanese researcher Dr. Hiroyuki Sumi had spent many years searching for a natural thrombolytic agent that could successfully dissolve blood clots associated with heart attacks and stroke. Finally in 1980, after testing more than 173 natural foods, Sumi found what he was looking for.

Some traditional Natto was dropped onto artificial thrombus (blood clot) in a petri dish and allowed to stand at 37 degrees C (approximately body temperature)—and over the next 18 hours, the thrombus around the Natto completely dissolved! Sumi named the newly discovered protease enzyme Nattokinase, which means “enzyme in Natto.” Dr. Sumi remarked that Nattokinase showed “a potency matched by no other enzyme.”5

How does Nattokinase work?

Nattokinase enhances our body’s natural ability to fight blood clots, and has an advantage over blood thinners because it has a prolonged effect without side effects. Nattokinase:

  • Supports normal blood pressure
  • Prevents blood clots from forming
  • Dissolves existing blood clots
  • Dissolves fibrin
  • Enhances the body’s production of plasmin and other clot-dissolving agents, including urokinase (an enzyme produced by the kidneys and found in the urine, which activates plasminogen)

Research studies

Nattokinase has been the subject of numerous scientific studies, including two small human trials. In 1990, Dr. Sumi’s research team published a series of studies demonstrating the fibrinolytic effects of Nattokinase.7 Here are some of the research highlights:

Nattokinase dissolves blood clots

Researchers from JCR Pharmaceuticals, Oklahoma State University, and Miyazaki Medical College tested Nattokinase on 12 healthy Japanese volunteers (6 men and 6 women, between the ages of 21 and 55). The researchers gave the volunteers 7 ounces of Natto (the food) before breakfast, and then tracked fibrinolytic activity through a series of blood plasma tests.

In one test, a blood sample was taken and a thrombus (clot) was artificially induced. The amount of time needed to dissolve the clot was cut in half within two hours of treatment, compared to the control group. Additionally, the volunteers retained an enhanced ability to dissolve blood clots for two to eight hours. Later, as a control, researchers fed the same amount of Natto to the same volunteers, and tracked their fibrinolytic activity. The tests showed no significant change from the initial test.6

In another study, Dr. Sumi’s team induced blood clots in a major leg vein in animals that had been given either four capsules of Nattokinase or four placebo capsules. Angiograms (x-rays of blood vessels) showed that the blood clots in the animals that received Nattokinase had completely dissolved within five hours of treatment, and that normal blood circulation had been restored. Blood clots in the animals who received the placebo showed no sign of dissolving 18 hours after the treatment.6

Researchers from JCR Pharmaceuticals Co. of Kobe, Japan, tested Nattokinase’s ability to dissolve a blood clot in the carotid arteries of rats. Animals treated with Nattokinase regained 62 percent of blood flow, whereas those treated with plasmin regained just 15.8 percent of blood flow.7

In another laboratory animal study, endothelial damage was induced in the femoral arteries of rodents that had been given Nattokinase. In normal circumstances, a thickening of the artery walls and blood clotting would occur, but they were both suppressed because of Nattokinase’s fibrinolytic activity.8

These tests all indicate that Nattokinase generates a heightened ability in the body to dissolve blood clots.

Helps reduce high blood pressure

Human volunteers with high blood pressure were given 30 grams of Natto extract (equivalent to 7 ounces of Natto food), orally for 4 consecutive days. In 4 out of 5 volunteers, the systolic blood pressure decreased on average from 173 to 154. Diastolic blood pressure decreased on average from 101 to 91. These impressive results represent about a 10.9 percent drop in systolic blood pressure and a 9.7 percent drop in diastolic blood pressure.569

A study of animals that were given Natto extract showed a significant drop in systolic blood pressure, also, from an average of 166 to 145 in just 2 hours, which further decreased to an average of 144 in 3 hours. This data represents an approximate 12.7 percent drop in systolic blood pressure within 2 hours.59

Restores blood circulation

This is one of the most dramatic case studies about the effects of Nattokinase. A 58-year-old man had a blood clot in the retina of his right eye that caused fluid build up and bleeding. He started losing his vision in that eye and was admitted to a university hospital, where researchers prescribed a three ounce dose of Natto to be taken before bed every night in order to get the benefit of Nattokinase.

The man’s bleeding completely stopped by the 10th day, and by the 20th day, his vision returned and he was released from the hospital. He continued to eat Natto twice a week. When he had a retinal angiogram two months later, it showed that the blood clot was completely gone.10

Excellent for periods of inactivity

This soy extract is considered extremely useful for those wanting a safe, non-drug, aspirin alternative for healthy blood flow. Over the past few years, medical professionals began alerting the public about the increasing evidence that long flights and car trips put people at risk for deep vein thrombosis (DVT)—a blood clot (thrombus) that develops in a deep vein, usually in the leg. DVT is more common in women than in men and in those over 40 years of age.

Deep vein thrombosis

DVT—blood clots inside veins found deep in extremities or body cavities—is a common disorder. A venous thrombus is a clump of blood cells, platelets, and fibrin (clot) which attaches to the inside walls of veins, can grow in size, and break off to travel downstream from the clot. If the clot stays localized, it can cause swelling and vein irritation. If part of it breaks off, it can cause blockage downstream, or become an embolus and result in a pulmonary embolus. In some instances, deep vein thrombosis may also contribute to other serious medical problems such as heart attack and stroke. Nattokinase can prevent DVT by not allowing the venous thrombus to develop.

How safe is Nattokinase?

As with any nutritional supplementation program, it is best to consult your physician before beginning a Nattokinase treatment program. Having said that, we can report that Nattokinase is safe for most people when used according to the recommended dosage. Some people should avoid Nattokinase. This includes people with bleeding disorders, such as hemophilia, or the group of diseases called hemorrhagic diathesis. Also, people with bleeding ulcers, bleeding hemorrhoids, or recent major trauma, or those who’ve had neurosurgery or a hemorrhagic stroke should not take Nattokinase. If you take heparin, Coumadin® or aspirin, use only under the close supervision of a medical doctor.

Healthy blood flow without the side effects of pharmaceuticals

Researchers have found that Nattokinase is four times more potent than plasmin, works more effectively than warfarin drugs, and doesn’t produce any side effects. On the other hand, the side effects associated with warfarin (such as Coumadin®) blood thinners are numerous and well documented. The short list includes:

  • Hemorrhage – internal bleeding
  • Abdominal pain and cramping
  • Diarrhea
  • Fatigue and lethargy
  • Feeling cold and chills
  • Liver damage
  • Loss of hair
  • Nausea


The traditional Japanese food Natto has been used safely for more than 1,000 years. The safety record of its potent fibrinolytic enzyme, Nattokinase, is based upon the long term traditional use of the food, and recent scientific studies.

Nattokinase has many benefits including its prolonged effects, cost effectiveness, and its ability to be used preventatively. It is a naturally occurring, food-based dietary supplement that has demonstrated stability in the gastrointestinal tract, as well as to changes in pH and temperature.

It would then seem prudent to add this effective natural product to your heart health preventive arsenal. Finally, a nutritional approach to reduce the health damaging, double-edged sword of plaque and plasma fibrins has arrived. Using a potent blend of oral EDTA chelation and vitamin K2 to reduce arterial plaque, and Nattokinase to prevent dangerous clots seems to make perfect sense.


  1. Prevent Heart Attack and Stroke with Potent Enzyme that Dissolves Deadly Blood Clots in Hours. Health Sciences Institute, March 2002.
  2. Heinrich, J. et al. Fibrinogen and factor VII in the prediction of coronary risk. Arterioscler Thromb 1994, 14:54-59.
  3. Sumi H. Interview With Doctor of Medicine Hiroyuki Sumi. Japan Bio Science Laboratory Co. Ltd.
  4. Suzuki Y, Kondo K, Ichise H, Tsukamoto Y, Urano T, Umemura K. Dietary supplementation with fermented soybeans suppresses intimal thickening. Nutrition. 2003 Mar;19(3):261-4.
  5. Prevent Heart Attack and Stroke with Potent Enzyme that Dissolves Deadly Blood Clots in Hours. Health Sciences Institute, March 2002.
  6. Sumi, H. et al. “Enhancement of the fibrinolytic activity in plasma by oral administration of nattokinase.” Acta haematol 1990, 84: 139-43.
  7. Fujita M, Hong K, Ito Y, Fujii R, Kariya K, Nishimuro S. Thrombolytic effect of nattokinase on a chemically induced thrombosis model in rat. Biol Pharm Bull 1995 Oct;18(10):1387-91.
  8. Suzuki Y, Kondo K, Matsumoto Y, Zhao BQ, Otsuguro K, Maeda T, Tsukamoto Y, Urano T, Umemura K. Dietary supplementation of fermented soybean, natto, suppresses intimal thickening and modulates the lysis of mural thrombi after endothelial injury in rat femoral artery. Life Sci. 2003 Jul 25;73(10):1289-98.
  9. Maruyama M, Sumi H. Effect of Natto Diet on Blood Pressure. JTTAS, 1995.
  10. Nishimura, K. et al. Natto diet was apparently effective in a case of incipient central retinal vein occlusion. Japan Rev Clin Ophthalmol 1994, 88:1381-85.

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