A fibrinolytic enzyme from fermented soybeans (natto). The best-supported effect is a modest blood-pressure reduction; the virally spread claim that nattokinase dissolves arterial plaque rests on weak (retrospective) evidence — the highest-quality RCT found no effect on atherosclerosis.
DoseWhat matters is not the milligram count but the enzyme activity in FU (fibrinolytic units). Preventively, ~2,000 FU/day is common; trials with cardiovascular endpoints used higher doses (up to 10,800 FU/day). Take on an empty stomach (~30–60 min before or 2 h after a meal) so the enzyme isn't broken down as a dietary protein.
· Fasted
