Ask the doctor

Can I take nattokinase instead of warfarin?

Q. I would like to find a safer, easier alternative to warfarin, which I have been taking for a couple of years. I have been hearing about nattokinase "" can I take it in place of warfarin?

A. Nattokinase, an enzyme extracted from fermented soybeans, helps dissolve blood clots "" in test tubes. But there's barely a scrap of evidence showing that taking nattokinase or eating natto (the fermented beans themselves) breaks up blood clots in human arteries or prevents them from forming in the first place.