Fats: moderate but necessary
Fats are edible fats, they are elements of animal or vegetable origin whose main components are the natural glycerides of fatty acids and other minor fats. Like carbohydrates, they are made up of carbon, hydrogen and oxygen.
Lipid structure
Fatty acids determine the basic structure of fats and, depending on them, their characteristics are different. These particularities are due to carbon, which can form single, double or triple bonds. The most common way to associate 2 carbons is the simple link, which is called saturated, but in some cases it is a double or triple link that is called unsaturated binding.
Saturated fats are stable so they are normally solid at normal temperature (20ºC). This is, for example, stearic acid, which is a fat present in butters and seams and which due to its difficulty of transport in blood can cause heart disease. Unsaturated binding fluids are liquids at the same temperature, such as oleic acid, the main component of olive oil, and linoleic acid, present in seed oils (sunflower, corn, soy, rapeseed oil, etc. ).
Fat in our body
Fats are essential for the proper functioning of our body, since there are many functions that are due to these fats. Among them are the following.
On the one hand, fats are the largest producer of energy; by oxidizing a gram of fat 9 Kcal are generated. In addition, fat intervenes in different body structures such as membrane cell, subcutaneous fatty tissue, etc. It is also important to regulate body temperature. They are also responsible for other fats such as bile fat, steroidal hormone, etc. They produce a feeling of satiety in the human body and form essential fatty acids that the body cannot produce otherwise: linoleic acid, linolenic acid and arachidonic acid. Finally, they are part of the different lipoproteins. In blood there are two: LDL and HDL. LDL carries liver fats to the cells and HDL from the cells to the liver, facilitating elimination and acting as a body protector.
Sources of fat
In order to carry out the functions of fat, the human body receives these substances from two main sources:
Animal fats
such as meat, sausages, milk and dairy, eggs, fish and butter. It can be of two types: what is evident, for example, what is in the flesh environment, and what is invisible — we all know that the egg has fat, but we do not see it. The amount of fat in animal products is variable, varying according to the type of animal, body part, breeding conditions (farm or hamlet) and the time of year. If we analyze meat, in general, the richest in fat are pork and lamb (20 -50%), in average grade we can take the veal, duck, turkey and ox (10-15%) and those that have the least are chickens, rabbits and horses (2-8%). On the other hand, its derivatives, such as sausages (chorizo, ham, pate, sausage, mortadella, black pudding, mondejo, etc.) contain at least 26% and a maximum of 50%. These sausages are very energetic, but they are not very rich in other ingredients, mainly in vitamins and minerals. 3-4% of the whole milk are lipids. Among dairy products, the less fat they have are yogurts (1-2%), while among cheeses there is a big difference, since the older the more fat the cheese has. For example, fresh cheese, known as Burgos cheese, has only 11% water and Idiazabal cheese 28-29%. As for eggs, it should be noted that the characteristics of each fraction are different, if the clear is only 0.20%, but the yolk 33%. The amount of fat also separates white and blue fish. White fish (cod, hake, tongue, rooster, etc.) are considered muscular (1-2% fat). Blue fish (sardines, anchovies, salmon, tuna, chicharro, etc.) contain between 8 and 13% fat.But we have to make a difference between all the products mentioned, since the type of fat of the animals of the year or the soil is very different. Those of ureta contain polyunsaturated fatty acids and those of saturated earth. For this reason, unlike fish, meat and eggs, it protects us against blood circulation and heart disease.
Vegetable fats,
fruits, vegetables, legumes and oils, for example. Only 1% of fruits and vegetables are fats, except olives, avocados and dried fruits, which can contain between 10-60%. In legumes, soy is the richest in fat (18%, compared to 1.5% of the rest). The oils come from fruits or seeds and are 100% lipid. The difference between olive oil and seed oils lies in the type of fatty acid, according to which the melting point is different. Since olives have a higher melting point, it is best for frying. Seed oils, by their lowest melting point, burn before and produce irritating substances for the body's mucous membranes. Of all these oils, coconut and palm oil is separated from the oil as they are more solid. They are widely used in pastry, as they are easy to use and have a very pleasant taste for the palate.
Margarine is a special product that cannot be found as in nature. The fatty acids of vegetable fats are enriched in hydrogen by an industrial process, that is, they are saturated and from there the solid product is obtained.
Cholesterol
Cholesterol is a special fat derived from other lipids. It is found exclusively in products of animal origin, that is, it never occurs in plant origin.
To a certain extent, cholesterol is necessary for our body because, among other functions, it participates in the formation of hormones. Its origin can be varied, either by the body (liver) or by food. The cholesterol produced by the body, therefore, should always be taken into account when completing our diet, so it is recommended to ingest a maximum of 300 mg/day of cholesterol.
Among foods rich in cholesterol and therefore necessary to measure their consumption, we can mention:
- Baby carrier: Liver: 300 mg/100 g Marrow: 2,000 mgr/100 g Kidneys: 400 mg/100 g
- Sausages: Paté: 300 mg/100 g
- Sweets: 225 mg/100 g
- Muffins: 130 mg/100 g
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