In the 80's, three retrospective studies showed an inverse relation between fish consumption and ischemic heart disease (IHD) mortality. In parallel, fish fats containing the polyunsaturated fatty acid eicosapentaenoic (EPA) were shown to impair platelet aggregation and thromboxane formation. The results of the large prospective Diet and Reinfarction (DART) Study in the secondary prevention of myocardial infarction have further supported the possibility of potential interrelationships between diet and thrombogenic factors with respect to IHD. More recently these concepts have been confirmed and extended in the prospective Lyon Heart Study. However, in the latter in addition to changes in the content of EPA, changes in other well known variables (i.e. leukocytes and vitamin E) often abnormal in subjects prone to arterial thrombosis have been found. From studies on polygenic disorders, we have learned that by lowering the threshold and becoming a susceptibility gene, a polymorphism can lead to an effect assuming that it is present in the appropriate milieu. Nutrients have been shown to affect major determinants of myocardial ischemia such as fibrinogen or factor VII. However, the extent to what these and other hemostatic variables have been affected in studies devoted to dietary prevention of ischemia remains presently elusive.