Yoga is known to induce beneficial effects on physiological, biochemical and mental functions in man. Its effects on blood coagulation are not known. A study was conducted in seven previously untrained male adults who underwent a combination of yogic exercises, daily for one hour, over a period of four months. Parameters of blood coagulation were estimated before and after the end of yoga training. The following changes were observed: Fibrinolytic activity increased significantly with a concomitant fall in fibrinogen; activated partial thromboplastin time and platelet aggregation time were prolonged; blood and plasma platelets showed a rise; and both haemoglobin and heamatocrit were raised at the end of the training. These findings suggest that yoga induces a state of blood hypocoagulability. The impact of yoga on prevention of cardiovascular and thrombotic disorders is obvious.

Sulfuric-flavored compounds were extracted from shiitake (Lentinus edodes) and their inhibitory activity against platelet aggregation was investigated. Platelet aggregation induced by arachidonic acid and U-46619, the analog of thromboxane A(2), was inhibited by the essential oil from shiitake that contained lenthionine as a major sulfuric compound. This result indicates that the inhibitory site of the shiitake flavor compounds would be different from that of garlic-flavor compounds because the latter inhibits the passage between arachidonic acid and thromboxane A(2). The effect of the synthesized lenthionine was almost equivalent to that of the essential oil, which indicates that the inhibitory activity of the essential oil from shiitake would be mainly attributed to lenthionine.