Betaine (trimethyglycine), isolated from sugar beet (Beta vulgaris) is a widely distributed natural compound and acts as a substrate in the betaine‐homocysteine methyltransferase process converting homocysteine to methionine. Homocysteine is a recognized risk factor for occlusive vascular disease. Betaine is currently registered as an orphan drug to control homocystinuria (Cystadane®, Orphan Medical Inc.). Although Betaine is also known to produce certain effects on the vascular system, the mechanism of these effects are not known. When repeatedly administered orally to normal human volunteers (n=12) at 6 g/OD for one week, Betaine exhibited hypocoagulant responses as measured by thrombelastographic methods. Blood samples drawn included a baseline, one week post oral administration of Betaine administration. Analysis of the plasma samples did not show any significant anticoagulant effects on the global clotting assays such as the PT, APTT. However, tissue factor pathway inhibitor (TFPI) antigen and functional levels were increased as shown below.