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Dangers of Nattokinase

Nattokinase, a natural supplement that can actually lower blood pressure and help your heart is being used by more and more people today. What is it and why is it so popular? Are there side effects? If so, what are they and are they dangerous?

Natto, is made from fermented soybeans, nattokinaise is extracted from natto. In Japan, Natto is eaten with rice for breakfast. It has a cheese-like smell and a nutty/salty flavor. Nattokinase tablets do not have the same taste or smell. It is believed to be of assistance in increasing the flow of blood and dissolving blood clots that can cause heart disease and strokes, the lowering of blood pressure.

Platelets in the blood can form clots in the blood vessels, restricting the blood flow which can cause many ailments including high blood pressure, heart attack and stroke. Nattokinase has been found to prevent this from happening.

Researcher, Hiroyuki Sumi, at the “Japan Bio Science Laboratory, discovered around 1980 that Natto had the ability to dissolve blood clots. He then purified and isolated the enzyme responsible and called it Nattokinase.

Physicians used to prescribe medications such as Coumadin in order to dissolve these blood clots and thin the blood, but many of the side effects are harmful, even deadly. Nattokinase should not be taken with aspirin, Coumadin or any type of blood thinner because it is a blood thinner. Combining it with other blood thinners can result in your blood being too thin and serious health issues. Nattokinase also contains a lot of Vitamin “K”, which can decrease the effects of other medications such as Coumadin. If you already have a bleeding disorder; do not take nattokinase.

There really have not been enough trials, with which to discover any side effects or dangers connected with nattokinase, however, a study has revealed that 7 out of 92 participants that took a placebo rather than nattokinase and developed a blood clot. None of the participants who took nattokinase developed clots. The effects of nattokinase used by pregnant and nursing women and children has yet to be discovered.

The only dangers that I can see from nattokinase would be if some people may be allergic to nattokinase, if you find that you are allergic or sensitive to this substance; discontinue its’ use immediately and contact your physician.

If it is made from soybeans that are grown in the United States or other countries that use many insecticides, pesticides or herbicides, the nattokinase may be contaminated by these dangerous chemicals. It is best purchased with all-organic extracts. If you cannot locate an extract that is 100% all-organic, contact your prescribing physician in order to locate a completely pure formula.

One study did find that nattokinase, when combined with a 300mg extract or capsule of red yeast rice, can actually lower cholesterol.

All-in-all, what I am finding about nattokinase is that is much safer than many prescriptions that are on the market. If you do experience any negative or hazardous side effects; report them to your doctor immediately and get treatment.


“Reverse Heart Disease Now”, by Stephen T. Sinatra, M.D. and James C. Roberts, M.D.