Health Benefits of Nattokinase: Evidence-Based Findings

| Modified on Jul 17, 2024
Nattokinase Daily Usage
Posted by Hollyhock (America ) on 03/02/2024

I have been taking nattokinase now for a couple months. Mostly because my family has a blood clotting disorder and I've had covid in the past. My question is,,, should I take a weekend break each week from taking it?

Nattokinase Tips
Posted by Prioris (Fl) on 02/21/2014

Serrapeptase does also include some fibrinolytic enzyme but can clear out debris. Yes, you can take nattokinase and serrapeptase at same time. The two enemies of these enzymes is acid and food particles.

I take K2 during the mid day with main meal. There are different theories on how K2 works. One says it goes to the liver and only is used if needed but don't know for sure. Nattokinase has a 3 to 8 hour window in which it is active. I take it morning and bedtime. So I just take K2 during my evening meal so outside the 8 hour windows.

My plan is to take K2 for 2 or 3 months - sort of like doing a cleansing of calcium from the arteries - then take it every second or third day dor maintenance. I'll experiment.

I would take a strong antioxidant like astaxanthin with your cod liver oil and butter. Fish oil without antioxidant protection can damage your brain.

Here is general guideline for the nattokinase

In regard to what dosage one takes with nattokinase and serrapeptase, it really depends how sick and symptomatic one is. Also age is a factor. As one ages, one can build up a lot of gunk in the arteries. Another factor is the profile of ones disease.

If your under 40 and relatively healthy, ones arteries are generally going to be in decent shape so I don't think one needs it. If one is relatively healthy and over 45, I would say 2000 FU on empty stomach before bed is all you need for preventative measure.

If one has anything related to heart disease and you are symptomatic, it means there are more serious problems going on. So probably a good idea to take higher dose just to be sure. I would dose nattokinase at dosage of 6000 FU 2X per day.

Whether one needs serrapeptase is not clear but it can't hurt and may help. PLus it works a little different than nattokinase. I'd go 80,000 IU three times a day. Take it with nattokinase. In my particular situation, I found I needed it.

You do this for 1 to 3 months. If you think you may have clots that need dissolving, it usually takes 2 to 3 months to take a lot of the clot away. Any symptoms you have should be gone within one month. For maintenance, taking 2000 FU when going to bed and upon wake. It's really ones call to decide whether serrapeptase is right for you and also length of time.

If one has cancer, i'd look into enzyme therapy also.

If one has a chronic illness then besides the aforementioned factors, you have to look at the profile of your disease. If people with your disease are dropping dead from heart disease or show any signs of blood coagulation then I would do a 1-3 month cleansing of your arteries then go on maintenance. So I'd follow what I said about heart disease and adjust it for ones age and other factors. i'd look into enzymes in general and experiment with them.

Everyone's situation can be different so the above is just some framework to operate within. you adjust it accordingly for your risk factors.

There are some rare blood clotting disorders that nattokinase doesn't treat so be careful. nattokinase can replace things like tpa, coumadin etc. It doesn't replace something like heparin. heparin by the way seems like one of the few positive prescription drugs that actually addresses the underlying problems.

Posted by RedCardinal (Minneapolis, MN) on 12/02/2023 3 posts

Be aware that there are different manufactured FU strengths per mg. You cannot go by mg, you want to go by FU's per serving. The best capsules have the lowest mg with the highest FUs

Where to Buy
Posted by Hollyhock (America ) on 10/31/2023

I read your report on nattokinase and decided to buy some recently hoping for help from the after effects of covid. But, I bought a product called "Nattozimes Exo/Endo Proteases" and now I'm thinking it's not nattokinase, the product description says "inspired by nattokinase". So probably a fake product?

Posted by Barbara (Washington) on 10/28/2023

My husband's bottle of nattokinase states that 1 softgel = 100 mg = 2000 FU. He takes 1 a day.

Blood Clots
Posted by CJ (Hendersonville NC) on 10/07/2023

I also would like to find a doctor to work with me in Hendersonville NC.

Posted by Linda (Virginia) on 08/11/2023

2,000 FU is 400 mg. Likewise, 4,000 FU is 800 mg. So if a person is taking 50 to 100 mg of Nattokinase they are taking a much lower dose than 2 or 4,000 FU. Amazon sells the higher dose of Nattokinase.

Blood Clots
Posted by kcm (western NE) on 04/27/2023

Samuel, I will recommend you contact Kyle Hampton, DO in Ft. Collins, and see if he might be able to help you.

Hope this might help.


Hyperviscosity, Heart Disease, Varicose Veins
Posted by Jim (CB, IA) on 03/19/2023

My girlfriend was diagnosed with PVCs, said she felt like she was having a heart attacked 24/7, doc did stress test, had her wear a heart monitor, then wanted to start her on 3 different meds (beta blocker, cholesterol med & something else heart related). We tried several OTC supps, a calcium/magnesium supplement gradually cured her in two weeks. She told her doc on a follow up visit what we did, he said his wife has the same condition and he would have to tell her about our solution. My girlfriend was taking a birth control prescription long term and I think that caused a magnesium deficiency as many prescription drugs do, I don't think she really needed the calcium in the supplement.

Hyperviscosity, Heart Disease, Varicose Veins
Posted by Jami (Texas) on 01/24/2023

If you please, have your cardiologist check specifically for PVCs [Premature Ventricular(sp) Compressions. They are usually benign but can feel very alarming. They are triggered by anxiety/stress. I have them and will be asking my cardiologist for Nattokinase when I see her next week. It's worth looking into.

Take Care,


Calf Pain
Posted by Lori (Chester. NY) on 01/21/2023

I've been experiencing calf pain, started talking 2 caps today. I hope It goes away, it's driving me crazy.

Hyperviscosity, Heart Disease, Varicose Veins
Posted by Mandy (Qld) on 01/12/2023

I use Nattokinase due to hyperviscosity, I have severe varicose veins, and hemorrhoids and cannot take blood thinners.

After multiple thromboses, 2 heart attacks, and a stroke, I found out about it on a coronary care website.

5 weeks ago, I began with 4000 FU per day increasing to 4x 4000 FU per day for 3 weeks. Will shortly drop back to 4000 FU per day. I use alongside K2 every second day. My issues have settled, my varicose veins are noticeably less, not hard and painful anymore. ( I have had this chronic complaint for approximately 35 years.)

To say that I am impressed by the results is an understatement.

My heartbeat is still often irregular however I am seeing better results and quicker recovery times.

Blood Clots
Posted by Samuel (Denver, CO) on 12/02/2022

I was on it... it was working great for years. I was forced to switch to Xarelto, which doesn't dissolve clots. I'd like to find a doctor that can work with me in the denver, co area with both

Calf Pain
Posted by Art (California) on 02/28/2022 2221 posts

Hi Deborah,

Glad to hear that you were able to resolve the pain in your calf using nattokinase!

There are different strengths of nattokinase. Could you tell us what strength and brand you used? Thank you!


Calf Pain
Posted by Deborah (MI) on 02/27/2022

I wanted to add my wonderful experience using Nattokinase I ordered off Amazon. I had a horrid knot in my left calf for three straight months. I thought it was a spasm but it never went away no matter what I tried. I think it was a clot. Took the Nattokinase and after 3 days the pain was totally gone. Took two 800mg capsules per directions on the label. So happy I tried this.

Fibrocystic Breasts
Posted by Martha (Keene, NH) on 01/12/2022

Glad the Nattokinase is working for you. My understanding is that it's best taken on an empty stomach; an hour before or 2-3 hours after a meal.

Nattokinase Side Effects
Posted by joe233 (United Kingdom) on 09/03/2021

Hi everyone,

Just thought it is worth sharing my experience with Nattokinase. Took it for a week without any other supplement, everything went fine even noticed a decline in the size of a small cyst.
Yesterday I took the supplement with Chaga mushroom, this morning I woke up and passed blood in my urine, little clots nothing major. Persisted throughout the day, went the GP they confirmed I have no infection and the GP and I both believe it is the Chaga interacting with the Nattokinase in a negative way, so I have no stopped Nattokinase and will stop all supplements for a few days to allow my body to reset.

Once this is done, I will resume with just chaga. Natto is good but make sure due to its blood thinning properties you are careful with what you mix it with.

Take care all, Joe

Trigeminal Neuralgia
Posted by Kay (MI) on 07/26/2021

Look up youtube Dr. Berg for trigeminal neuralgia. It is the best treatment for trigeminal neuralgia. It is the only thing that would stop my pain and it is so simple. Dr, Berg has so many good excellent topics and the comments on his youtube videos show how much he is loved. Hope this helps.

Trigeminal Neuralgia
Posted by Natalia (Romania) on 07/19/2021

I had debilitating trigeminal neuralgia. Let say pain score 1-10 I have had 15. Classic therapy Gabapentin 600 mg, Stugeron 50 mg, Diclofenac or either Naproxen, Magnesium bisglicinate gave me just temporary relief.

Then I took 200 mg of Nattokinase because it was throbbing in spite of all this and started in the middle of the night while I was sleeping, so to take all this again was a bit too much. After about 1 hr pain stopped. In the morning I had just a vague sensation of throbbing maybe 1-2 out of 10.

So I took 200 mg of Nattokinase more and NO PAIN. AND I DID NOT TAKE ANYTHING FROM THE LIST ABOVE.

I am so happy! I will continue to have Nattokinase 100 mg as a support for the next few days. I am an emergency physician myself and I can say this supplement is miraculous. In the way to replace Aspirin, but now with your post, it saved my life. Thank you.

Posted by Ampy (FL) on 12/01/2020


I just read that you were taking CoQ10 and now added the Nattokinaise and it has helped your migraines. I have migraines now for 40+ years I have been taking CoQ10 for years, my question is, do you take both of these at the same time before a meal on an empty stomach? I was told to take my supplements (which we take a lot of them) after our night time meal. So that's why I'm asking. Would love to know how you are taking this. I will try anything for migraines. Thanks in advance. Ampy

Atrial Fib
Posted by Sharon (Wisconsin) on 12/01/2020


Have you tried magnesium supplementation for A-Fib? Lots of great information out there by Dr. Carolyn Dean.

Deep Vein Thrombosis
Posted by Prioris (Fl, Usa) on 03/05/2014

The solution for DVT is fairly simple - use nattokinase. It should resolve the pain and problem within a month. Take higher dosage for first couple weeks.

Look for my posts on nattokinase by searching earth clinic "+prioris+nattokinase".

You will also find a lot of positive anecdotal reports on internet from people.

Posted by Mary (Newport, RI) on 05/14/2018

I have had poor circulation my whole life, especially cold hands and feet, which got worse when I hit my 60s. I started on 1 capsule of nattokinase at dinnertime and rapidly felt more warmth in my hands. Then about a week later I had more warmth in my feet. This improvement to my extremities is remarkable to me because I have tried other supplements to improve circulation like horse chestnut but they absolutely did not help.

I will continue to take 1 capsule of 2,000 a day. Only side effect is that I tend to bruise more easily but that's okay.

Atrial Fib
Posted by Hwkmn05 (Nh) on 06/19/2020 109 posts

Pat, how goes the afib battle? I found a Vit D protocol that seems to work for many. Also, high dosage of Lugol's Iodine for some. Hope all is well.

Nattokinase Side Effects
Posted by Kevin (Wv) on 12/25/2018

If you've only been taking the Nattokinase for a short time then it hasn't had the time to compensate for your meds. If on meds your bp is 130/80 chances are that with no meds it would be about 180/110.

Only taking Natto for one week it's likely it's lowered your bp 13/9 from what it would have been if you weren't on any meds.

This is why one should always take the natural supplement at least a month before starting to taper slowly off the meds while keeping close watch on bp.

Best Way to Take Nattokinase
Posted by Destiny (Alexandria, Va) on 06/19/2018

Just reiterating what Joe Tulsa said - Nattokinase is to be taken on an empty stomach ... at least one hour before eating or 2-3 hours after eating.

It is my understanding that you get the best results when taken on an empty stomach because when you take it with food, the enzymes will work on breaking down any protein you have just eaten instead of the problem proteins you want it to work on.

I take it along with Serrapeptase and I leave them on my bathroom counter so I can take them when I wake up in the night to use the restroom. That way, by the time I wake up the hour has passed and I can eat my breakfast without worrying! It is great that it's working for you - it will probably work even better on an empty stomach :-)

Carotid Artery Circulation
Posted by Whimofnature (Austria) on 04/25/2018

Day #3: no tinnitus

Carotid Artery Circulation
Posted by Whimofnature (Austria) on 04/24/2018


Today is day #2 on Nattokinase. 2 hours after intake I experienced high pitched tinnitus for 5 seconds. Same yesterday.

Nattokinase Side Effects
Posted by Vincent (Australia) on 03/01/2018

Hi Reba, Thick blood can often be too many animal products.Cut down for a month and see how you feel.Most cheeses are very very high in fats.Best Wishes, Vince.

Posted by Marguerita (Usa) on 01/18/2018

To strengthen my veins, I take standardized hawthorn, standardized ginkgo, and a plant-derived vitamin C.

Posted by Hisjewel (Usa) on 01/16/2018

Nattokinase is an excellent blood thinner. It is worth reading up on and studying. I have read that older adults that means like sixty, should take Pine Bark or Boron or another supplement that strengthens blood vessels when using nattokinase long lengths. It is said that this rule actually applies when taking any blood thinner such as aspirin etc.

Nattokinase has helped me with circulation problems. I do use Pine bark also.


Fibrocystic Breasts
Posted by Joe (Tulsa) on 01/09/2018

Nattokinase is to be taken on an empty stomach according to the instructions.

Atrial Fib
Posted by Hwkmn05 (Nh) on 01/07/2018 109 posts

Pat, 100mg = 2,000 FU

Atrial Fib
Posted by Pat (Pa) on 12/27/2017

Thanks, but what is 2000 FU? The Nattokinase I find is 50 mg or 100 mg! Don't know how much to take! Never saw any labeled 2000 FU

EC: Pat, FU is the acronym for Fibrinolytic Units, which are defined as enzyme activity units specific for breaking down fibrin. If you search on Amazon for Nattokinase, you will see various brands of Nattokinase have 2,000 - 4,000 FU per capsule. More info regarding Fibrin Units in a Q&A on Amazon here.


Posted by Pat (Pa) on 12/26/2017

thx Elaine! I started using Nattokinase as blood thinner for Afib about 6 mos ago Only my bottle says 50 mg and another at store said 100 mg. Why does everyone say 2000 FU? Am I taking right dose? I take 1 a day! No side effects. Hope it is working. I think it is!

Nattokinase Side Effects
Posted by Reba (Alabama ) on 07/01/2017

Is it possible for Nattokanisse to raise blood pressure? I am taking myself off of the drug lisinopril and trying to cure my high blood pressure naturally. I have been taking one and sometimes two Nattokinesse capsules for one week and my blood pressure is ranging around 167/101. It didn't seem to get that half before I started taking this supplement. Has anyone else been affected in this way when taking Nattokanisse?

Nattokinase Side Effects
Posted by Bethany (Boulder, Co) on 04/15/2017

I started using Nattokinase supplementation about a year ago after reading about it online in numerous articles are research docs on pubmed. I wanted to take something to prevent blood clots as heart disease and strokes runs in one side of my family. I think this is an amazing supplement, but wanted to warn that people it is extremely powerful (more so than aspirin) and people should always start off with a very low dose for at least a week. I consistently get a high pitched ringing in my one of my ears if I go off it and then start up on it. I like to take time off from all of my supplements, so I do this every week or so (take a few days off from supplements, that it). The high pitched EEEEEE happens once or twice after about 4 hours of taking nattokinase and then no more, but it always happens. I now take only 1/3 of a capsule per day. I pour open the capsules and pour 1/3 of the contents into a 1/2 cup of water and drink that down.

The other thing worth mentioning is to be very careful if you take nattokinase with Advil as it may cause blurry vision. I took an advil at night a few days ago to help with muscle stiffness and the next morning my vision was extremely blurry for the most of the day. Advil can cause blurry vision (one of the listed side effects), but I have never had that before. Worth noting. Would love to hear from other's experience. Can't find much about feedback from real people about nattokinase side effects on the web.

Atrial Fib
Posted by Robert Henry (Ten Mile , Tn) on 04/01/2017

PAT,,,,,,,, I have no clue, but I take one capsule a day that is 2,000 FU / capsule. I take that because that is what my integrative doctor gives his wife for her A FIB. I take one Rx and several other supplements that are in EC's archives. I do bruise easily, but maybe that goes with age.


Atrial Fib
Posted by Pat (Pa) on 03/31/2017


Does anyone know how much Nattokinase to take everyday for blood thinning? I don't know whether to take 50mg daily or if I need 100mg daily? I also take VitE, Garlic and a good Fish oil but thought I should start that also! Don't want to go on Pharmaceutical blood thinners! Don't like that idea!

Carotid Artery Circulation
Posted by Glen (Montauk, NY) on 12/11/2016

I started taking Nattokinase (2000 fu, once a day) a few months ago instead of a daily aspirin for heart attack and stroke prevention after reading studies on it. Interestingly, I got a slight case of tinnitus for a few minutes within 2 hours only the first two days of taking it.. just in my left ear. Felt like the inner ear was adjusting to increased blood flow. The noise went high pitched and then quiet. I also got a temporary pain in my left temple/brain. I suspect thought I don't know for sure this was a sign of carotid artery circulation improvement. Well I ran out of my nattokinase a couple of weeks ago. I ordered it online and had a week off of it while I waited for it to arrive. I started back on a few days ago and got the exactly same symptoms. Just for a day as my body adjusted to the supplement again. I am wondering if anyone else on this site had the same symptoms on Natto?

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