Nattokinase and Blood Thinners

Dear Dr. Meletis,

Following successful treatment for Atrial Fibrillation (AF) my mother has been prescribed aspirin as a blood-thinning agent (i.e. to help prevent blood clots leading to stroke etc.). She used to take Nattokinase instead of aspirin, but has been advised not to take both at the same time. Her doctors are unaware of Nattokinase, and so she has stopped taking it. Please could you advise whether it is safe to take Nattokinase as well as aspirin (and if so, the safe dosage levels). Please could you also provide some information her doctors could use on the relative strength of Nattokinase as a blood thinner compared with aspirin. Many thanks.

Kind regards,

Mr. R.

Dear Mr. R.,

Below is an article that you can share with your mother’s physician. The article is from a 2009 medical journal.

Relative to taking both aspirin and Nattokinase together, if one was to do so, starting with a low dose such as found in Nattokinase+ once per day would be a starting place. However, I can’t advise such a combination, since I do not know your mother’s other health concerns. Her physician could order a PT/PTT bleeding time to get a baseline, then incorporate the Natto, if her doctor chooses to and retest her bleed times, in this manner, or her doctor’s preferred technique. Many of my patients incorporate both; the concern is to make sure that excess blood thinning does not occur. 

You will also want the doctors in general to measure her C-reactive protein, homocysteine and fibrinogen to help control cardiac risk factors. Additionally, getting a 25-OH vitamin D test would be prudent, so would having her get tested for sleep apnea if she snores.

The information shared here is educational and is not intended as either diagnosis or treatment. Conferring with her physician prior to supplementing will be important. 

See below for the article abstract on Nattokinase.

Sincerely,

Chris D. Meletis, ND

Hsia CH, Shen MC, Lin JS, Wen YK, Hwang KL, Cham TM, Yang NC. Nattokinase decreases plasma levels of fibrinogen, factor VII, and factor VIII in human subjects.Nutr Res. 2009 Mar;29(3):190-6

Nattokinase, a serine proteinase from Bacillus subtilis, is considered to be one of the most active functional ingredients found in natto. In this study, we hypothesized that nattokinase could reduce certain factors of blood clotting and lipids that are associated with an increase risk for cardiovascular disease (CVD). Thus, an open-label, self-controlled clinical trial was conducted on subjects of the following groups: healthy volunteers (Healthy Group), patients with cardiovascular risk factors (Cardiovascular Group), and patients undergoing dialysis (Dialysis Group). All subjects ingested 2 capsules of nattokinase (2000 fibrinolysis units per capsule) daily orally for 2 months. The laboratory measurements were performed on the screening visit and, subsequently, regularly after the initiation of the study. The intent-to-treat analysis was performed on all 45 enrolled subjects. By use of mixed model analysis, a significant time effect, but not group effect, was observed in the change from baseline of fibrinogen (P = .003), factor VII (P < .001), and factor VIII (P < .001), suggesting that the plasma levels of the 3 coagulation factors continuously declined during intake; also, the extents of decrease were similar between groups. After 2 months of administration, fibrinogen, factor VII, and factor VIII decreased 9%, 14%, and 17%, respectively, for the Healthy Group; 7%, 13%, and 19%, respectively, for the Cardiovascular Group; and 10%, 7%, and 19%, respectively, for the Dialysis Group, whereas blood lipids were unaffected by nattokinase. No significant changes of uric acid or notable adverse events were observed in any of the subjects. In summary, this study showed that oral administration of nattokinase could be considered as a CVD nutraceutical by decreasing plasma levels of fibrinogen, factor VII, and factor VIII.