NattoPine combines nattokinase, an enzyme derived from fermented soybeans, with Pinus massoniana pine bark extract (PMBE), a source of proanthocyanidins. Each ingredient contributes a different kind of support for healthy circulation: nattokinase has been studied for normal fibrinolytic activity and fibrinogen metabolism, while pine bark extract provides antioxidant support. Here is the research behind this two-ingredient formula, and why combining them is the smart choice.