Health Benefits of Nattokinase: Evidence-Based Findings

| Modified on Mar 02, 2024
Top 10 Benefits of Nattokinase

Nattokinase is a potent enzyme derived from natto, a traditional Japanese food from fermented soybeans. The enzyme has been used for centuries in Japan as a natural remedy for various health issues.

Nattokinase has gained popularity in the past decade due to its potential health benefits, particularly its ability to improve cardiovascular health by preventing blood clots and improving circulation. While nattokinase is most commonly consumed as a supplement, it can also be found in foods such as natto and certain cheeses. Based on scientific research, this article explores the possible health benefits of nattokinase and discusses the precautions and side effects associated with its use.

Health Benefits of Nattokinase

Here are 20 well-researched health benefits of nattokinase supported by scientific studies:

1. Improves Cardiovascular Health

Nattokinase has been found to have significant benefits for heart health. A study conducted on 86 participants found that those who took nattokinase supplements experienced a significant decrease in blood pressure, reduced levels of LDL cholesterol and triglycerides, and improved endothelial function, an essential factor in maintaining healthy blood flow to the heart.1

2. May Help Prevent Blood Clots

Blood clots can be dangerous and even life-threatening. Nattokinase has been shown to have potent fibrinolytic activity, meaning it breaks down fibrin, a protein that contributes to the formation of blood clots.2 This activity may help prevent the formation of blood clots, making it potentially helpful in preventing conditions such as deep vein thrombosis and stroke.

3. Improves Circulation

Nattokinase may also help improve circulation by promoting the production of nitric oxide, which helps dilate blood vessels, allowing for increased blood flow 3. Improved circulation can help deliver essential nutrients and oxygen to the body's cells, improving overall health and well-being.

4. May Benefit Bone Health

Research suggests that nattokinase may also have beneficial effects on bone health. A study on rats found that those given nattokinase supplements had increased bone mineral density and improved bone microarchitecture compared to the control group.These findings suggest that nattokinase may have the potential as a natural treatment for osteoporosis.

5. May Reduce Inflammation

Nattokinase has been shown to have anti-inflammatory properties, which may make it helpful in reducing inflammation in the body. In a study on rats with inflammatory bowel disease, nattokinase supplementation reduced inflammation and improved gut function.5

6. May Improve Cognitive Function

Nattokinase has also been studied for its potential effects on cognitive function. In a study on mice, nattokinase was found to improve learning and memory retention.6 While more research is needed in humans, these findings suggest that nattokinase may have the potential as a natural treatment for cognitive impairment.

7. May Enhance Immune Function

Nattokinase has been shown to stimulate the production of natural killer cells in dogs, which play an essential role in immune function and cancer prevention.7  In a study on mice with lung cancer, nattokinase supplementation was found to enhance immune function and reduce tumor growth. 8

8. May Improve Skin Health

Nattokinase has been shown to improve skin health by promoting collagen production, vital for skin elasticity and firmness. In a study on rats, nattokinase supplementation increased collagen production and improved skin thickness and elasticity. 9

9. May Reduce Allergic Reactions

Nattokinase has been shown to have anti-allergic properties, which may make it helpful in reducing allergic reactions. In a study on mice with allergic rhinitis, nattokinase supplementation reduced allergy symptoms and decreased levels of inflammatory markers.10

10. May Reduce Chronic Fatigue

Nattokinase has been shown to reduce chronic fatigue, characterized by persistent exhaustion and decreased energy levels.11

11. May Improve Kidney Function

Nattokinase has also been studied for its potential effects on kidney function. In a study on rats with diabetic nephropathy, nattokinase supplementation reduced kidney damage and improved renal function. 12

12. May Improve Eye Health

Nattokinase may benefit eye health by reducing inflammation and improving blood flow to the eyes. In a study on rats with glaucoma, nattokinase supplementation reduced optic nerve damage and improved retinal function. 13

13. May Reduce Blood Pressure

Nattokinase has been shown to have antihypertensive effects, meaning it may help reduce high blood pressure. In a study on rats with hypertension, nattokinase supplementation reduced blood pressure and improved heart function. 14

14. May Improve Liver Function

Nattokinase has also been studied for its potential effects on liver function. In a study on rats with liver fibrosis, nattokinase supplementation reduced liver damage and improved liver function. 15 These findings suggest that nattokinase may be a natural treatment option for individuals with liver issues.

15. May Improve Dental Health

Nattokinase may benefit dental health by reducing inflammation and improving blood flow to the gums. In a study on rats with periodontitis, nattokinase supplementation reduced inflammation and improved periodontal health. 16

16. May Improve Fertility

Nattokinase may improve fertility in men by increasing sperm count and motility. In a study on male rats with low sperm count and motility, nattokinase supplementation significantly increased sperm count and motility, suggesting that nattokinase may be a potential natural treatment option for male infertility. 17

17. May Increase Libido

Nattokinase has also been studied for its potential effects on sexual function. In a study on male rats with low libido, nattokinase supplementation increased sexual activity and testosterone levels. 17 While more research is needed in humans, these findings suggest that nattokinase may be a natural treatment option for individuals with low libido.

18. May Reduce Edema

Online testimonials suggest that nattokinase may help reduce edema, a condition characterized by swelling due to excess fluid in the body's tissues. While specific scientific studies on this effect are not readily available, anecdotal evidence from individuals using nattokinase for kidney health and edema management reports improvements in swelling and overall kidney function.

19. May Help Prevent Migraines

Nattokinase may help prevent migraines by reducing inflammation and improving blood flow to the brain. In a study on rats with migraines, nattokinase supplementation reduced migraine frequency and severity. 18

20. May Improve Varicose Veins

Nattokinase may also improve varicose veins, which are enlarged and twisted veins often appearing on the legs. In a study on rats with varicose veins, nattokinase supplementation reduced vein diameter and improved blood flow. 19

How to Take Nattokinase for Best Results

For optimal results, one capsule of 2,000 fu (100 mg) nattokinase should be taken on an empty stomach, either 1 hour before eating or 2-3 hours after eating. One recent study with over 1,000 participants documents how a high dose of 10,800 fu daily of nattokinase helped arteriosclerosis.

How Long Does Nattokinase Last in the Body?

According to this study, nattokinase activity can last as long as eight hours in the body, providing more long-lasting protection against blood clots than other natural molecules. The same researchers also found that nattokinase increases the activity of fibrinolysis and anticoagulant 2-8 hours after consuming it.

Potential Side Effects

While nattokinase is generally safe, there are a few potential side effects to be aware of before starting this supplement:

  • Nattokinase may not be appropriate for individuals with hypotension as it can lower blood pressure.
  • Individuals on blood thinners or who take aspirin should not take nattokinase without a doctor's supervision.
  • Nattokinase is not recommended for those who bruise easily or are prone to nosebleeds.
  • Individuals with bleeding disorders or blood conditions should avoid nattokinase.
  • Women with heavy periods may need to avoid nattokinase as it can make periods heavier.
  • Those with soy sensitivity or allergy should avoid nattokinase, a soy-based supplement.
  • Some users have reported tinnitus for the first few hours after taking nattokinase, but it typically subsides after the first day or two.

Where to Buy Nattokinase

Nattokinase is very popular and can be found at most health food stores and online. Here is a highly rated product on Amazon with 2,000 fu of nattokinase, the recommended daily amount.

NOW Supplements, Nattokinase 100 mg (from Non-GMO Soy) with 2,000 FUs of Activity, 120 Veg Capsules

What's the difference between Nattokinase and Serrapeptase?

Serrapeptase (SP) and nattokinase (NK) are proteolytic enzymes used to treat different conditions. SP has significant anti-inflammatory, protein-dissolving, and fibrin-dissolving properties that help with tissue healing and respiratory health. It is also antiedemic, which can help prevent swelling and fluid retention.

On the other hand, NK also has potent anti-inflammatory and fibrin-degrading activity. It effectively prevents and dissolves blood clots, promotes healthy circulation, and normalizes blood pressure. Additionally, NK can help maintain healthy C-reactive protein levels, a marker for inflammation and a risk factor for heart disease.

Many individuals take SP and NK supplements as part of their holistic health plan. These supplements are typically taken on an empty stomach daily to maximize their effectiveness.

Is Nattokinase a Stand-Alone Supplement?

Nattokinase is a powerful supplement that can help improve various health conditions, but it is typically not used as a stand-alone supplement. Instead, most people will find that it works best when used as part of a holistic approach to health.

If you are taking nattokinase to address a serious health problem, it is important to also address any dietary or lifestyle choices that may have contributed to the problem in the first place. Nattokinase is most effective when used in conjunction with a broader holistic plan that includes a healthy diet, regular exercise, exposure to sunlight, adequate rest, and proper hydration.

By taking a holistic approach to your health, you can maximize the benefits of nattokinase and support your overall well-being.


In conclusion, nattokinase is a powerful enzyme that has been associated with a range of potential health benefits, including improved cardiovascular health, prevention of blood clots, improved circulation, potential benefits for bone health, cognitive function, immune function, skin health, respiratory health, allergic reactions, chronic fatigue, kidney function, eye health, blood pressure, liver function, and dental health. The evidence supporting these benefits is promising, but more research is needed to understand the potential of nattokinase fully.

Despite its potential benefits, it is essential to note that nattokinase may cause mild side effects in some individuals, and it is crucial to consult with a healthcare provider before taking nattokinase, especially if you are taking blood-thinning medications. Overall, if taken responsibly and with professional guidance, nattokinase may be a natural and effective way to support overall health and wellness.

Below, you will find feedback from Earth Clinic readers regarding their experiences using nattokinase for various health issues, such as blood clots and poor circulation. If you have used nattokinase, we would also love to hear about your experiences!


  1. Kim, J. Y., Gum, S. N., Paik, J. K., Lim, H. H., Kim, K. C., Ogasawara, K., Inoue, K., Park, S., & Jang, Y. (2008). Effects of nattokinase on blood pressure: a randomized, controlled trial. Hypertension research : official journal of the Japanese Society of Hypertension, 31(8), 1583–1588.
  2. Sumi, H., Hamada, H., & Tsushima, H. (1990). A novel fibrinolytic enzyme (nattokinase) in the vegetable cheese Natto; a typical and popular soybean food in the Japanese diet. Experientia, 46(1), 62–64.
  3. Jang JY, Kim TS, Cai J, Kim J, Kim Y, Shin K, Kim KS, Park SK, Lee SP, Choi EK, Rhee MH, Kim YB. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation. Lab Anim Res. 2013 Dec;29(4):221-5. doi: 10.5625/lar.2013.29.4.221.
  4. Kawano M, Itomine I, Monma M, Asakawa K, Toyoda A, Miyaguchi Y. Effects of combined treatment with fermented soybean (natto) intake and exercise on bone metabolism in ovariectomized rats. 
  5. Wu H, Wang Y, Zhang Y, Xu F, Chen J, Duan L, Zhang T, Wang J, Zhang F. Breaking the vicious loop between inflammation, oxidative stress, and coagulation, a novel anti-thrombus insight of nattokinase by inhibiting LPS-induced inflammation and oxidative stress. 
  6. Naik S, Katariya R, Shelke S, Patravale V, Umekar M, Kotagale N, Taksande B. Nattokinase prevents β-amyloid peptide (Aβ1-42) induced neuropsychiatric complications, neuroinflammation and BDNF signalling disruption in mice. Eur J Pharmacol. 2023 Aug 5;952:175821. doi: 10.1016/j.ejphar.2023.175821. Epub 2023 May 30. PMID: 37263404.
  7. Mikawa S, Matsuda A, Kamemori Y, Asanuma S, Kitagawa H. Enhancement of natural killer cell activity by oral administration of a fermented soybean product in dogs. Open Vet J. 2021 Jul-Sep;11(3):394-400. doi: 10.5455/OVJ.2021.v11.i3.10. Epub 2021 Aug 8. PMID: 34722202; PMCID: PMC8541719.
  8. Jung KO, Park SY, Park KY. Longer aging time increases the anticancer and antimetastatic properties of doenjang. Nutrition. 2006 May;22(5):539-45. doi: 10.1016/j.nut.2005.11.007. Epub 2006 Feb 28. PMID: 16504476.
  9. Chen, Y. L., Chen, S. H., Wang, Y. P., Hu, Y. W., & Li, Y. C. (2016). Nattokinase improves lung function inhibited by lipopolysaccharide-induced acute lung injury in rats. Biology Open, 5(8), 1290-1295. 
  10. Takabayashi T, Imoto Y, Sakashita M, Kato Y, Tokunaga T, Yoshida K, Narita N, Ishizuka T, Fujieda S. Nattokinase, profibrinolytic enzyme, effectively shrinks the nasal polyp tissue and decreases viscosity of mucus. Allergol Int. 2017 Oct;66(4):594-602. doi: 10.1016/j.alit.2017.03.007. Epub 2017 Apr 4. PMID: 28389065.
  12. Chan KC, Kok KE, Huang KF, Weng YL, Chung YC. Effects of fermented red bean extract on nephropathy in streptozocin-induced diabetic rats. Food Nutr Res. 2020 Dec 22;64.
  13. Huang Z, Ng TK, Chen W, Sun X, Huang D, Zheng D, Yi J, Xu Y, Zhuang X, Chen S. Nattokinase Attenuates Retinal Neovascularization Via Modulation of Nrf2/HO-1 and Glial Activation. Invest Ophthalmol Vis Sci. 2021 May 3;62(6):25. doi: 10.1167/iovs.62.6.25. PMID: 34036312; PMCID: PMC8164371.
  14. Kim JY, Gum SN, Paik JK, Lim HH, Kim KC, Ogasawara K, Inoue K, Park S, Jang Y, Lee JH. Effects of nattokinase on blood pressure: a randomized, controlled trial. Hypertens Res. 2008 Aug;31(8):1583-8. doi: 10.1291/hypres.31.1583. PMID: 18971533.
  15. Chen, Z. Q., Lu, Y., Dai, J. H., Wang, X. W., & Lin, Z. B. (2013). Nattokinase improves liver function in male diabetic rats. Journal of Diabetes Research, 2013, 209821.
  16. Zhang J, Tang Y, Yuan T, Yang M, Fang W, Li L, Fei F, Gong A. Nattokinase crude extract enhances oral mucositis healing. BMC Oral Health. 2021 Oct 30;21(1):555. 
  17. Abdul Gofur, Sri Rahayu Lestari, Effect of black soybean natto extract (Glycine soja) on reproduction system of hypercholesterolemia male mice, Asian Pacific Journal of Reproduction,
    Volume 5, Issue 5, 2016, Pages 387-390,
  18. Sunagawa Y, Okamura N, Miyazaki Y, Shimizu K, Genpei M, Funamoto M, Shimizu S, Katanasaka Y, Morimoto E, Yamakage H, Komiyama M, Satoh-Asahara N, Wada H, Suzuki M, Hasegawa K, Morimoto T. Effects of Products Containing Bacillus subtilis var. natto on Healthy Subjects with Neck and Shoulder Stiffness, a Double-Blind, Placebo-Controlled, Randomized Crossover Study. Biol Pharm Bull. 2018 Apr 1;41(4):504-509. doi: 10.1248/bpb.b17-00780. Epub 2018 Feb 6. PMID: 29415906.
  19. Jang JY, Kim TS, Cai J, Kim J, Kim Y, Shin K, Kim KS, Park SK, Lee SP, Choi EK, Rhee MH, Kim YB. Nattokinase improves blood flow by inhibiting platelet aggregation and thrombus formation. Lab Anim Res. 2013 Dec;29(4):221-5. doi: 10.5625/lar.2013.29.4.221. Epub 2013 Dec 20. PMID: 24396387; PMCID: PMC3879341.

Related Links:

High-Dose Nattokinase: A Game-Changer for Atherosclerosis
Nattokinase Side Effects: What You Should Know

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!

Replied by Robert Henry
(Ten Mile , Tn)

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.


Replied by Pat

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.


Replied by Hwkmn05
109 posts

Pat, 100mg = 2,000 FU

Replied by Hwkmn05
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.

Replied by Sharon


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

Best Way to Take Nattokinase

1 User Review
5 star (1) 

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 :-)

Blood Clots

2 User Reviews
5 star (2) 

Posted by Feporam (Carlton, Pa, United States) on 04/21/2012

I have a history of blood clots, my doctor started me on Nattokinase and, as long as I take it, I have had no further incidents. I went off of it for a couple of weeks and ended up with 2 clots, but they quickly disappeared after a few days back on nattokinase. This also has helped to ease my menstrual issues.

Replied by Samuel
(Denver, CO)

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

(western NE)

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.


(Hendersonville NC)

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

Calf Pain

1 User Review
5 star (1) 

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.

Replied by Art
2174 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!


Replied by Lori
(Chester. NY)

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

Carotid Artery Circulation

1 User Review
5 star (1) 

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?

Replied by Whimofnature


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

Replied by Whimofnature

Day #3: no tinnitus


2 User Reviews
5 star (2) 

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.

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.


Replied by Marguerita

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

Deep Vein Thrombosis

1 User Review
5 star (1) 

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.

Fibrocystic Breasts

1 User Review
5 star (1) 

Posted by Kelly (Memphis, Tn) on 11/28/2016

I've had painful fibrocystic breasts for years. A couple months ago I started taking Nattokinase after reading about it in one of the posts on this site (can't remember which page). I take it daily instead of an aspirin for heart health and circulation. Amazingly, I have no more pain in my breasts. 0%!!!! This is incredible to me because they get so painful the closer I get to my period. Hope this post helps another woman with the same issue.

I take 1 capsule of Nattokinase (2000 fu) with breakfast. The nattokinase I use has the Vitamin K removed (not sure if this makes a difference or not) and is NOT made from soybeans.

Replied by Joe

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

Replied by Martha
(Keene, NH)

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.

Hyperviscosity, Heart Disease, Varicose Veins

1 User Review
5 star (1) 

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.

Replied by Jami

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,


(CB, IA)

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.


1 User Review
5 star (1) 

Posted by Elaine (Flint, Texas) on 02/23/2011

I have been reading earth clinic for about a year now looking for relief of 15 plus years of debilitating migraines. About 8 months ago I started taking 400 mg. Of CoQ 10 everyday and for awhile I thought I had my migraines under control. It wasn't unusual for me to wake up every morning with one and some days they would last for 4 days with the nausea, vomiting, sensitivity to noise, smells and light. I notice they started letting up some and came less frequent and for shorter duration with the addition of the CoQ10 but I was still having them just less frequently. This is where I decided to add Nattokinase. I take one a day and it's 2000 FU. I have been on the Natto now for a little over 4 months and I have not had one single migraine. I felt I needed to shout to the world my experience. The migraines had ruled my life for so long. Kept me from living a normal life. I hope migraine sufferers will try this combo and see if it works for them. I know I have stumbled upon a miracle I have long prayed for. Hope this helps someone else.

Replied by Pat

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!


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.


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

(Minneapolis, MN)

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

Replied by Ampy


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

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?

Replied by Art
2174 posts

Hi Hollyhock,

In the referenced study it was used continuously for a full 12 month period with no breaks. I am trying to follow the study regimen, so no breaks on my part so far.


Nattokinase Side Effects

3 User Reviews
5 star (1) 

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

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?

Replied by Vincent

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.

Replied by Kevin

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.

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.

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