Lipids or fats in nutrition

Opinions on the importance of lipids in the diet are very marked by the idea that they are usually associated only with the negative effects caused in the body by diets with excess fats. Such a criterion, product of the lack of information, can lead us to do without the necessary amount of one of the essential nutrients for the maintenance of health.

Lipids are a group of molecules made up of carbon, hydrogen and oxygen that can also contain phosphorus, sulfur and nitrogen. Biochemically, they are insoluble in water, but soluble in organic solvents. Together with carbohydrates, they provide the major source of energy for the organism.

Classification of lipids: Lipids can be divided into three major groups:

• Phospholipids.

• Triglycerides (fats).

• Sterols (cholesterol).

Phospholipids: they are a type of lipid composed of an alcohol molecule, to which two fatty acids and a phosphate are attached. Soy, milk and eggs contain phospholipids. Functions of phospholipids:

• They are a structural component of the cell membrane.

• They participate in the activation of enzymes.

• They are part of the pulmonary surfactant, which prevents the collapse of the alveoli during expiration.

• They are part of bile, they are responsible for making cholesterol soluble, to prevent the formation of cholesterol gallstones.

• They act as arachidonic acid donors for the synthesis of cell signaling substances.

Triglycerides: they are made up of three fatty acid molecules and one glycerol molecule. Within the lipid group, most of the fats we consume come from the triglyceride group.

Triglycerides are contained in butter, meat fat, vegetable oils, fish oil and hydrogenated fats produced in industry, such as margarine.

Classification of triglycerides: Triglycerides present in the human diet can be divided into three major groups:

• Saturated fatty acids (SFA).

• Unsaturated fatty acids.

• Trans fatty acids.

Saturated fatty acids (SFA): are those that in their chemical structure only have single bonds between carbon atoms, this property gives them great stability and the characteristic of being solid at room temperature.

Saturated fatty acids are found in large quantities in foods of animal origin such as butter, meat fat and also in some foods of vegetable origin such as coconut and palm oils.

Impact of saturated fatty acids on the body:

• They are more difficult to use by the organism due to the limited possibilities of combining with other molecules.

• Under certain conditions they can accumulate inside the arteries forming plaques giving rise to arteriosclerosis.

Unsaturated fatty acids: these are fatty acids with carbon double bonds and are usually liquid at room temperature. According to the number of carbon double bonds, they are classified as follows:

• Monounsaturated fatty acids (MUFA): have only one carbon-carbon double bond. Commonly called omega-9. They are contained in olive oil, avocado and nuts.

• Polyunsaturated fatty acids (PUFA): have two or more carbon-carbon double bonds. They are commonly identified as omega-3 and omega-6. They are contained in some fish, nuts, vegetable oils, such as sunflower, soybean and corn oils.

Repercussion for the organism of unsaturated fatty acids:

• It avoids cholesterol excesses.

• It favors the hepatic synthesis of bile salts, which contributes to the assimilation of fats.

• It satisfies the nutritional needs of fatty acids.

• Prevents cellular aging and also the formation of cancerous cells, due to its antioxidant action.

Trans fatty acids: they are obtained from the industrial processing of hydrogenation of fats, to modify their physical and sensory characteristics. An example is the solidification of liquid vegetable oil for the manufacture of margarine.

Impact of trans fatty acids on the body:

• Their consumption should be moderate because although they are of vegetable origin, in the industrial process of hydrogenation they undergo modifications in their configuration, acquiring the trans configuration, giving rise to fatty acids whose behavior is more similar to that of saturated fatty acids (SFA), destroying the qualities of oils of vegetable origin.

• They contribute to the elevation of harmful cholesterol, while lowering healthy cholesterol levels, increasing the risk of cardiovascular disease.

• It is associated with the increase of brain, metabolic, diabetic diseases and some types of cancer.

Sterols (cholesterol) are molecules formed by a structure of between 27 and 29 carbon atoms. They are found in cell membranes and in the blood plasma of our body. Meat, eggs, offal, fish, shellfish and egg yolk contain cholesterol. Characteristics of cholesterol:

• The cholesterol necessary for the organism is obtained by two ways, most of it is manufactured by the liver and the other is obtained from food.

• In a healthy organism, cholesterol levels remain constant, since the production of cholesterol in the liver decreases when the levels of cholesterol in the diet increase.

• Cholesterol can be harmful to health if its levels are too low or too high. In healthy organisms, both imbalances can be corrected by maintaining a balanced diet.

Cholesterol functions:

• It provides the necessary consistency to the membrane of all cells.

• It actively participates in the elaboration of sexual and adrenal hormones.

• It participates in the elaboration of biliary secretions necessary to digest food.

Some consequences of excess lipids in the body:

• It conditions health risk factors such as overweight and obesity.

• Elevation of the concentration of cholesterol and triglycerides in the blood, increasing the risk of suffering cardiovascular and cerebrovascular diseases.

Some consequences of lipid deficiency in the body:

• Lack of vitamins a, d, e, k, which are necessary for the health of organs and systems, mainly skin, bones and cardiovascular system.

• Lack of healthy fats such as omega-3 and omega-6 fatty acids, which can cause vision, skin and immune system disorders.

• Energy deficits in the body that would force the body to degrade protein for energy, affecting the ability to build muscle.

• Problems in cell formation and function, lipids are involved in the construction of the membranes that surround and protect cells.

• Testosterone insufficiency causing low libido in both men and women.

• Hydrocortisone insufficiency affecting the metabolism of carbohydrates, fats and proteins.

• Lipids. Together with carbohydrates, they provide the major source of energy for the body. They can be divided into three large groups: phospholipids, triglycerides and sterols.

• Phospholipids perform important functions in the organism, among which is to participate in the activation of enzymes.

• The triglycerides present in the human diet can be divided into three main groups: saturated fatty acids, unsaturated fatty acids and trans fatty acids.

• Under certain conditions, saturated fatty acids can accumulate inside the arteries forming plaques, giving rise to atherosclerosis.

• The use of unsaturated fatty acids is highly recommended for health, because they avoid cholesterol excesses, prevent cellular aging and the formation of cancerous cells.

• The consumption of trans fatty acids. It is associated with an increased risk of cardiovascular, cerebral, diabetic diseases and some types of cancer.

• Cholesterol can be detrimental to health when its levels are too low, or too high, both conditions can be resolved in healthy organisms by maintaining a balanced diet.