Amyloid-Degrading Ability of Nattokinase From Bacillus subtilis natto

This laboratory study tested whether nattokinase, the fibrinolytic enzyme from natto, can break down amyloid fibrils — the protein aggregates implicated in Alzheimer’s disease and other amyloid disorders.

In the test tube, nattokinase degraded amyloid fibrils with activity comparable to known protein-cleaving enzymes (proteinase K and subtilisin Carlsberg), an ability not shared by trypsin or plasmin. The authors speculated about therapeutic potential for amyloid-related diseases.

This is purely in vitro work. An enzyme dissolving amyloid in a dish has no demonstrated relevance to what an orally consumed supplement does in a living brain — where absorption, the blood-brain barrier, and physiology all intervene. It is far upstream of any clinical claim.

We rate the evidence limited. It is basic biochemistry of interest to researchers, providing no support for nattokinase as a treatment for amyloid disease or any cardiovascular condition.