Enfermedad cardiovascular y grasas: “amigo o villano”

Dietary fatty acids and cholesterol are the main determinants of cardiovascular disease. In the last 25 years our traditional dietary pattern has tended to include higher total fat content and lower nutritional quality, which will have negative effects on our state of health. In this review, we provide an overview of current knowledge on the influence of different dietary fatty acids and cholesterol on cardiovascular risk. There has been renewed interest in the different hypercholesterolemic and thrombogenic actions of saturated fatty acids because of the irruption on the market of foods prepared with tropical oils (coconut, palm, kernel), which are very rich in saturated fat. Partial or completely hydrogenated fats are also involved in the preparation of numerous prepared foods (confectionery, bread and cakes, breakfast cereals, spreads, snacks, frozen dishes, etc.) because of consumers’ growing demand for these types of product. Hydrogenated fats generate the formation of trans fatty acids, whose action on lipid metabolism is more harmful than that of saturated fat: they not only increase concentrations of low-density lipoprotein cholesterol (LDLc) but also diminish concentrations of high density lipoprotein cholesterol (HDLc) and increase concentrations of triglycerides, fibrinogen and Lp(a). At the other end of the spectrum, consumption of unsaturated fats, mainly monounsaturated fatty acids from olive oil, remains high. In addition to their well-known neutral action on lipid metabolism, many of their beneficial effects probably reside in the minority components of olive oil (phenolic compounds). The beneficial effects of these compounds on the development of arteriosclerosis go beyond their remarkable antioxidant action. Among the polyunsaturated fats, ω-3 fatty acids, derived from fish or from foods with a high α–linolenic acid content (nuts, soy, linseed or borrago oils) have mainly antiarrhythmic effects, which are responsible for the decrease in episodes of sudden cardiac death. However, the preventive effects of these fatty acids on new cardiovascular events remain controversial. The actions of dietary cholesterol on cardiovascular risks are lower than expected because their absorption depends on several factors. Some of these factors are dietary (interference with phytosterols, for example) but genetic factors, such as the apoprotein E genotype, are also involved in the absorption or transport of cholesterol. Industrial biotechnology is looking for new combinations of fatty acids that would meet consumers’ demand for new foods. Despite the doubts that can arise when faced with a label of vegetable oil, as a synonym for healthy fat, we can still select healthy dietary patterns, based on foods produced by the soil: fresh fruit and vegetables, cereals and pulses, tree nuts and olive oil. We can also reduce our intake of fatty meats, whole dairy products, refined sugars, confectionery, and frozen dishes.