FUNCTIONAL FOOD-SCIENCE AND THE CARDIOVASCULAR-SYSTEM

Cardiovascular disease has a multifactorial aetiology, as is illustrat ed by the existence of numerous risk indicators, many of which can be influenced by dietary means. It should be recalled, however, that only after a cause-and-effect relationship has been established between th e disease and a given risk indicator (called a risk factor in that cas e), can modifying this factor be expected to affect disease morbidity and mortality. In this paper, effects of diet on cardiovascular risk a re reviewed, with special emphasis on modification of the plasma Lipop rotein profile and of hypertension. In addition, dietary influences on arterial thrombotic processes, immunological interactions, insulin re sistance and hyperhomocysteinaemia are discussed. Dietary Lipids are a ble to affect lipoprotein metabolism in a significant way, thereby mod ifying the. risk of cardiovascular disease. However, more research is required concerning the possible interactions between the:various diet ary fatty acids, and between fatty acids and dietary cholesterol. In a ddition, more studies are needed with respect to the possible importan ce of the postprandial state. Although in the aetiology df hypertensio n the genetic component is definitely stronger than environmental fact ors, some benefit in terms of the development and coronary complicatio ns of atherosclerosis in hypertensive patients can be expected from fa tty acids such as ol-linolenic acid, eicosapentaenoic acid and docosah exaenoic acid. This particularly holds for those subjects where the hy pertensive mechanism involves the formation of thromboxane Az and/or a lpha 1-adrenergic activities. However, large-scale trials are required to test this contention. Certain aspects of blood platelet function, blood coagulability,:and fibrinolytic activity are associated with car diovascular risk, but causality has been insufficiently proven. Noneth eless, well-designed intervention studies should be initiated to furth er evaluate such promising dietary components as the various n-3 and n -6 fatty acids and their combination, antioxidants, fibre, etc. for th eir effect on processes participating in arterial thrombus formation. Long-chain polyenes of the n-3 family and antioxidants can modify the- activity of immunocompetent cells, but we are at an early stage of exa mining the role pf immune function on the development of atherosclerot ic plaques. Actually, there is little, if any, evidence that dietary m odulation of immune system responses of cells participating in atherog enesis exerts beneficial effects. Although it seems feasible to modula te insulin sensitivity and subsequent cardiovascular risk factors by d ecreasing the total amount of dietary fat and increasing the proportio n of polyunsaturated fatty acids, additional studies on the efficacy o f specific fatty acids, dietary fibre, and low-energy diets, as well a s on the mechanisms involved are required to understand the real funct ion of these dietary components. Finally, dietary supplements containi ng folate and vitamins B-6 and/or B-12 should bd tested for their pote ntial to reduce cardiovascular risk by lowering the plasma level of ho mocysteine.