WARNING!
Natto and Serrapeptase enzymes are often closely compared and sometimes combined in remedies. BUT I URGE CAUTION TO READERS OUT THERE.
See my earlier comment about how Serrapeptase may actually damage joints further.
Using Serrapeptase to dissolve internal scar tissue can normally be a good thing, (ie endometriosis) unless that kind of scarring is also what patches-up joint damage (ie, splits in synovial tissue layers). Then it can cause more problems. A friend and I both found this out the hard way, repeatedly.
Another thing I am now very surprised to read is that Serrapeptase helps produce more Tumor Necrosis Factor - Alpha (TNF-A).
TNF-A has benefits in normal, youthful balance. BUT, it often gets overproduced with age and really contributes to autoimmune disorders and joint damage.
This may have been another reason why Serrapeptase, (for all its good benefits), was so awful to me and my friend's finger joints. This was in spite of my friend, at first calling it a "natural Ibuprofen." The damage soon followed.
I personally suspect the same, potential joint problems with other, inflammatory-reducing proteolytic enzymes I tried since then. It's just they are not as strong as Serrapeptase.
I would also be very wary of trying Serrapeptase to treat Rheumatoid inflammatory symptoms, because these are often treated with anti TNF-A drugs instead.
But so far, I've not noticed any of these concerns from using Nattokinase alone.
Natto seems to have noticeably improved my leg circulation, which is great news, but that's about it
It still doesn't help my allergies and sinuses like Serrapeptase miraculously did - (but at least it's not further injuring my hands.)
I hate throwing cold water on all the good things about Serrapeptase because it really benefited me too. But it also can have a pretty severe Dark Side for some conditions. So, you've been warned...
