Fats in cardiovascular disease

| There is scientific evidence of the effect of the quality and quantity of fats consumed on health and the development of cardiovascular diseases

The fats that we consume with food are a heterogeneous set of substances composed mainly of triglycerides (that is, fatty acids linked together), but also by cholesterol, sterols and phospholipids. All of them fulfill important functions in the human being: they serve as an element to store energy, as fuel to produce energy, they are part of the cell membranes, they participate in the synthesis of hormones and bile acids, and participate in the aggregation of platelets and in the activation of coagulation.

Therefore, the diet must include fat in its composition. There are several types of fats of interest in cardiovascular risk:

• Saturated fats: They are triglycerides that contain "simple" fatty acids (without any double bonds in their chemical structure). unfavorable health effects by increasing blood levels of LDL cholesterol or "bad" cholesterol, raise blood pressure figures, increase the risk of thrombosis and increase the risk of suffering from cardiovascular disease.

They are present in all animal fats (red meat, milk and derivatives); but there is also saturated fats of vegetable origin. Palmitic acids (palm and palm kernel oil) and lauric (coconut oil) are saturated fats of vegetable origin, and also unfavorable for cardiovascular health. These fats generally appear on the labels of the products that contain them (pastry products, industrial pastries and precooked foods) as "vegetable oil". On the other hand, stearic acid, present in chocolate, and which is also a saturated fatty acid, behaves beneficially on cardiovascular health given its metabolization in the body to oleic acid (monounsaturated).

• Monounsaturated fats: They are triglycerides that contain fatty acids in whose structure there is a single double bond. Here are included the fatty acids of the omega 9 family (n-9), whose main representative is oleic acid, present in olive oil and nuts. These fats significantly improve cardiovascular risk. They slightly lower LDL cholesterol or "bad" cholesterol and slightly increase HDL cholesterol or "good" cholesterol; LDL cholesterol is also less damaging to the arterial wall. In addition, monounsaturated fats would improve blood pressure, blood thrombosis capacity, inflammation in the arterial wall, and the metabolic control of type 2 diabetes mellitus.
• Polyunsaturated fats: They are triglycerides whose fatty acids contain two or more double bonds in their chemical structure. Two families are included: omega 6 fatty acids (n-6), from vegetables, and Omega-3 fatty acids (n-3), found in fish and shellfish and nuts. They are very beneficial, especially omega 3s, for cardiovascular health.
• Fatty acids n-6 have as their representative linoleic acid, which we find in vegetable oils (sunflower, corn, soy) and in nuts. They have a lowering effect on LDL cholesterol and HDL cholesterol. Their role in the prevention of cardiovascular disease is unclear. But instead, if they substitute for saturated fats, yes reduce the risk of cardiovascular disease.
• Fatty acids n-3 they are found in fish (especially blue fish) and shellfish; its representatives are eicosapentaenoic acid and docosahexaenoic acid. They are also in vegetables (soybean, canola-rapeseed oils, green leafy vegetables, and walnuts); the representative is alpha linolenic acid. The n-3 fatty acids produce numerous beneficial effects: decrease the blood level of triglycerides and increase that of HDL cholesterol, reduce blood pressure, prevent arterial thrombi, reduce the incidence of ventricular arrhythmias after a myocardial infarction, and reduce the risk of sudden death in previously healthy individuals . In short, they clearly reduce the incidence of cardiovascular disease or its recurrence or death from it in individuals who consume them.
• Hydrogenated fats or trans fats: They are fats not present in nature until their appearance in the human food industry. Originate from unsaturated fatty acids by a hydrogenation process. Hydrogenation consists of adding, at high temperatures, hydrogen atoms to unsaturated fatty acids (generally monounsaturated acids). Thus, from a liquid fat (monounsaturated) a more solid fat is formed that can be said to be "of vegetable origin", and which, in addition, makes the products made with it last longer, keep it for longer. time the desired consistency and have a better flavor. For all these reasons, these fats are ideal in industrial bakery and in the production of hard consistency margarines. However, despite being "vegetable", trans fats have harmful effects on blood fats by increasing LDL cholesterol values ​​and reducing HDL cholesterol, they have a detrimental effect. enhance inflammation on the arterial wall, increase the risk of developing type 2 diabetes mellitus and increase the risk of cardiovascular disease, even more than saturated fats. The more liquid the margarine is, the less trans fatty acids it contains.
• Diet cholesterol: Interestingly, cholesterol in food does not have great effects on the blood cholesterol. This is true for the majority of individuals, but we also find some individuals who greatly modify their blood cholesterol compared to any change in the amount of cholesterol in their diet; They are the so-called "great responders" or "hyperresponders." Another important aspect to take into account is the relationship of dietary cholesterol with the risk of cardiovascular disease; the results are not conclusive in this sense, there are studies in favor and others against. But, in these studies that find a causal relationship between dietary cholesterol and the onset of cardiovascular disease, the risk is very low. Cholesterol is found only in food of animal origin, such as meats, organ meats, cold cuts, whole dairy products (milk, cheese, butter), eggs, fish and shellfish. But since many of these foods also contain saturated fat in their composition, it is not advisable to consume them in excess. On the other hand, it is important to note that the frequent indication in products made "does not contain cholesterol" does not presuppose that they are healthy either, as they may contain saturated fats. In this sense, the recommendations on eggs is a moderate consumption (2-3 eggs a week).

There is scientific evidence of the implication of the quality and quantity of fats consumed in human health, either in the development (saturated fatty acids and trans acids) or in the prevention (monounsaturated acids and omega-3 acids) of the cardiovascular diseases. We must take fat, but not of any kind and in any quantity. It is recommended that of the total energy that is incorporated with food, around 30-35% comes from fat: less than 7% in the form of saturated fat, 7-10% as polyunsaturated fat, and 15-20% as fat monounsaturated.

It is currently recommended that the relationship between the n-3 polyunsaturated fatty acids (alpha linolenic) and n-6 (linoleic) in the diet is approximately 1: 3 to 5; however, more clinical studies are needed to corroborate its clinical benefit.