Lipids are a group of natural organic compounds soluble in organic solvents and not soluble in water.
They play a very important role in our body, but not everyone realizes how important.
The list of their properties and functions is extremely extensive, I will cite only a few.
Fats are important components of biological membranes, nervous tissue, they are an important element that is part of many hormones, cholesterol and important substances inside cells. In addition, fats play a protective role in our body
-insulation (protect against heat loss),
– keep internal organs in a fixed position, preventing their displacement,
– they protect them from mechanical injuries.
As I wrote earlier, these are just a few of their functions that they perform, but on their basis we can state that without their participation our body could not exist.
Lipids are the most caloric nutrients of all (1g – 9 kcal). They improve the taste of our dishes and create a feeling of fullness between meals.
In addition, fats found in natural foods contain fat-soluble vitamins and essential fatty acids.
The average fat requirement (according to the study) varies between 15 and 30% of the total caloric demand.
Specific fats are composed of 3 molecules of fatty acids and one molecule of alcohol – glycerol. A fatty acid molecule consists of an even number of carbon, hydrogen and oxygen atoms. Depending on the type of fatty acids forming a given type of fat, you can distinguish between saturated, monounsaturated and polyunsaturated fats. Saturated fatty acids do not have double bonds in their composition, monounsaturated acids have one such bond, whereas polyunsaturated fatty acids have two or more.
Saturated, monounsaturated and polyunsaturated acids can be formed in the human body. However, there are polyunsaturated acids that the body can not produce, and so they must be supplied from food. They carry the name of the essential unsaturated fatty acids. These include linoleic acid and α-linolenic acid and other compounds belonging to their families (eg eicosapentaenoic acid – EPA, docosahexaenoic acid – DHA).
So much for the introduction.
In the following, I would like to present the issues that are most often addressed.
1.) Food fat = fat gain – so many people think.
First of all, we have to realize that the growth of body fat corresponds to a positive energy balance, not the presence of fat itself.
This issue also applies to reduction cycles. We think that by eliminating fats we will achieve a faster effect. Therefore, fats are replaced with carbohydrates, thus depriving the body of a nutrient that is extremely important as mentioned above.
When comparing fats with carbohydrates, carbohydrates have a greater tendency to build spare fat. Why?
Well, excess carbohydrates (glucose) goes to fat cells, where it converts into the active form of glycerol. For the construction of fat cells, fatty acids are needed in addition to glycerol, which in the case of excess carbohydrates may also come from them. Therefore, excess carbohydrates will always turn into fat tissue.
Foods rich in fat, of course, also affect the growth of fat, but not to the extent of carbohydrates, because the fat of fat can provide fat cells only fatty acids (glycerol supplied by fats is not activated by our body).
In addition, with a diet rich in carbohydrates, and also low in fat, the body increases the synthesis of fatty acids.
So let’s remember not to combine too much fat with carbohydrates (especially saturated fats) because it does not have a beneficial effect on our body composition and is not healthy.
2.) Another issue is what fats should I include in my diet and where can I find particular types of fatty acids?
When choosing fats for our diet, we must remember their appropriate proportions (more on below). A frequently asked question is also the question whether to choose animal or vegetable fats. Due to the right proportions, we must consider both the first and the second in the diet.
These fats differ mainly in the type of fatty acids and the content of vitamins. In animal fats (except for fish fats) mainly saturated fatty acids occur, whereas in vegetable fats unsaturated. In some animal fats – milk and fish – there are vitamins A and D that are not found in vegetable fats. Vegetable fats, on the other hand, contain vitamin E, which is found only in small amounts in animals.
In my opinion, we should include in our diet first of all
– as a source of fatty acids saturated with natural butter, coconut oil, lard (about which more when frying),
– as a source of monounsaturated fatty acids extra virgin olive oil, rapeseed oil with a reduced content of erucic acid (Canola),
– as a source of fatty acids polyunsaturated fish oil, linoleic oil, walnut oil, pumpkin seed oil.
We should also remember that a large part of the fats we eat are invisible fats, i.e. those that form part of such products as meat, fish, eggs and dairy products.
3.) What should be the proportions of fatty acids in my diet?
Regarding the ratio of saturated fatty acids to monounsaturated and polyunsaturated fatty acids, their proportions should be 1/1/1. This proportion, contrary to appearances, is easy to keep choosing from the products I mentioned above.
However, when it comes to the proportions of omega 3 to omega 6, the matter is not so easy. The proportions should range from 15 to 11 (preferably 11). The case is not so easy because omega 6 is the dominant product in the vast majority of products. To meet the proportions given by me, add oil, omega 3 capsules to your diet, and oily fish is a rich source of omega 3.
Remember also that the intake of essential fatty acids (EFAs) must be related to the appropriate intake of vitamin E (tocopherol – an antioxidant) to control and reduce antioxidant. For every 1 g of EFA, 0.4 – 0.6 tocopherol should be used.
4.) Should you include margarine in your menu?
Margarine is a fat with a solid consistency at room temperature for the production of which vegetable oils are used. Vegetable oils, as you know, have the consistency of liquids, so they must take appropriate processes to change this consistency into a solid one. This process is called the hydrogenation process. It involves saturation of double bonds with hydrogen. This process takes place at elevated temperature, pressure and in the presence of catalysts. These conditions are radically different from those that occur in our bodies. As a result of hydrogenation, vegetable oils are deprived of all ingredients such as vitamins, carotenoids, tocopherols, whereas omega 3 and 6 fats are transformed into hydrogenated trans fats.
Trans-isomers increase the level of insulin in the blood, allow the flow of foreign substances into the interior of the cells causing them to mutate, increase cholesterol levels in the blood and disrupt the body’s immune processes. They may also act unfavorably on the fetus.
Taking the above into consideration, one should strive to reduce the content of trans isomers not only by eliminating margarine but also by eliminating from their diet such products as fast food, chips, powdered soups, sweets.
4) Frying – another frequently discussed topic.
It is a heat treatment process based on heating the food in a fat environment, which leads to increased calorie content. During frying, many unfavorable compounds are formed. One of them are peroxides, which are the result of free radicals decay. During frying, oxidation of vitamins also takes place, and fatty acids are transformed into toxic substances. As we can see the frying process is an unfavorable process and we should strive to eat as little fried products as possible. However, if we decide to fry, we should pay attention to it
– the amount of fat used for this process was as small as possible,
– the duration was as short as possible – in the conditions of short frying, oxidative changes are just started,
– pour the fat used,
– do not let it burn,
– take care of the proper temperature of the fat used (too low tempertaura causes fat to penetrate, too high formation of toxic compounds),
– take care of the right type of fat.
Regarding the type of fat, oils with a high content of polyunsaturated fatty acids are best used raw, without heating. Do not use them for frying because of the content in them, the large number of double bonds, to which oxygen joins, causing the hydrotherapy. The more double bonds contain fatty acid, the faster the setting process takes place.
Also, butter should not be used for frying, because under the influence of high temperature the fat contained in it is decomposed very quickly to produce harmful substances (eg acrolein, free radicals).
The relatively short-term heating is suitable for oils with a lower content of polyunsaturated fatty acids, e.g. rapeseed oil, olive oil.
Lard is suitable for heat treatment even at high temperatures.
The usefulness of individual fats for frying can be confirmed by their smoking temperature – this is the moment when the product begins to degrade and release carcinogens under the influence of the temeprture.
The temperature of smoking of some fats (degrees C)
– palm oil – 240,
– animal fat – 220,
– olive oil – 210,
– soy milk, sunflower – 170,
– a grape seed, corn – 160,
-marargine – 150,
– butter – 110.
The ideal temperature for frying is about 180 degrees C.
You can read also: The role and qualities of fat in the diet