[Dietary intake and hyperlipoproteinemias]

The role of nutrition on the prevalence of cardiovascular diseases is largely, but not exclusively linked to the effect of dietary intake on plasma lipids and lipoproteins. Among the regular nutrients, saturated fats, and to a lesser extent cholesterol, do raise plasma cholesterol, namely in the LDL fraction. Classical recommendations consist of reducing dietary lipids to < or = 30% and saturated fats to < or = 10% of total caloric intake. However, recent findings demonstrate that not all saturated fatty acids are exerting a similar effect on cholesterol metabolism. Likewise, whether saturated fatty acids should be most appropriately replaced by carbohydrates or monounsaturated lipids is a matter of controversy, especially when managing patients with high plasma triglycerides and/or insulin resistance. In contrast, there is currently some agreement for limiting the intake of polyunsaturated fatty acids; and for considering separately the essential n-6 or omega 6 fatty acids (largely present in many vegetable oils) and the n-3 or omega 3 derivatives (present in algae and fish oils). This leads to evaluate other properties of fatty acids (and of other dietary components) such as the capacity to modulate inflammatory responses and thrombotic reactions, as well as to influence cell sensitivity to stimuli, cell to cell communication, and cell proliferation. Finally, the confirmation that peroxidative processes are playing an important role in lipoprotein metabolism and the development of atherosclerotic lesions largely explains the present interest to antioxidants.