Fats – role, demand, sources. Dietary fat sources

Proven content

Many people associate fats with unnecessary kilograms. They are partly right, but it is worth knowing that fats also play an important role in the human body. What is the body’s need for fats? What fats are needed and which are better to avoid? What foods are high in the fats you need?

What are fats – structure and division

The common name of fats covers lipids, glycerol esters and fatty acids. The vast majority of fats do not give off any smell, they are insoluble in water and lighter than water. The aggregate state of fats depends on what acidic residues make up the fat molecule. The main component of edible fats are triglycerides, i.e. esters composed of three fatty acid molecules and one glycerol molecule. Triglycerides that are found in the human body come from food or have been produced endogenously in the liver, adipose tissue, mucosa of the small intestine or the mammary gland.

The structure of fatty acids differs in the length of the carbon chain as well as in the number and position of double bonds. Fatty acids are made of carbon, hydrogen and oxygen. Fatty acids can form 6 to 24 carbon molecules. Therefore, depending on the number of carbon molecules and the length of the carbon chain, short-chain, medium-chain and long-chain fatty acids are distinguished. The foods we eat on a daily basis usually contain long-chain fatty acids. Short and medium chain fatty acids are found, for example, in milk fats and butter.

The division of fats depends on the criteria of this division. Fats are divided according to their origin, the presence of double bonds, their chemical structure and the state of aggregation.

Want to learn more about the different types of fat in your diet? Check: Margarine is not bad at all

Breakdown of fats by origin

The simplest and most understandable division of fats is based on their origin. This breakdown lists:

1. vegetable fats – they are mainly obtained from rape seeds, sunflower seeds, soybeans or linseed. There are also vegetable fats made from hazelnuts, coconut and walnuts. Vegetable fats can also be obtained from the flesh of avocado, palm oil or sea buckthorn. Vegetable fats are a source of unsaturated fatty acids, which is why they most often come in liquid form. Monounsaturated and polyunsaturated fatty acids are responsible for maintaining the proper level of cholesterol and triglycerides. They also have a positive effect on blood pressure. Vegetable fats are a rich source of vitamin E and polyphenols, i.e. antioxidant substances;
2. animal fats – they are produced by smelting them from comminuted tissue. Animal fats at room temperature usually take the form of a solid, due to the fact that they are rich in saturated fatty acids. The exception in this case are oils that are obtained from fish. These oils are a rich source of polyunsaturated acids. Fats consisting of saturated fatty acids are resistant to high temperature and therefore ideal for frying; 
3. artificial and modified fats – they arise as a result of industrial hydrogenation, i.e. hardening of vegetable oils. During this process, vegetable oil is enriched with hydrogen molecules and exposed to very high temperatures.

If you want to know which fats are harder to digest, check out: Hard to digest fats

Division of fats due to the presence of double bonds

The second important division of fats is division due to the presence of double bonds. In this case, you can replace:

1. unsaturated fats – the human body does not produce unsaturated fats on its own, but they are necessary for proper functioning. Unsaturated fats are divided into monounsaturated and polyunsaturated. Most unsaturated fats are found in vegetable oils, nuts or fish fats. Among unsaturated acids, special attention is paid to omega-6 and omega-3 fatty acids. Unsaturated acids in the diet help prevent atherosclerosis, heart attacks and strokes. They lower the level of LDL cholesterol and regulate the level of triglycerides in the blood. Try a dietary supplement with omega-3 acids – N ° 1 Omega VIT. You will find it on Medonet Market at a promotional price;
2. saturated fat – these are fats mainly of animal origin. They are found in meat, butter, cheese and eggs. Saturated fats are also found in palm and coconut oil. Saturated fatty acids are those in which all carbon atoms are linked together by a single bond, while unsaturated acids have double bonds. Consumption of saturated fat should be monitored, for example, the American Heart Association recommends that saturated fat should cover a maximum of 5-6 percent of your daily energy needs. This means that by consuming about 2000 kcal a day, saturated fat should be about 120 kcal, which is about 13 grams of saturated fat per day.

If you want to learn more about palm oil, check out: Palm Fat – Learn the Facts and Myths About Palm Oil

Classification of fats due to their chemical structure

Another known breakdown of fats takes into account their chemical structure as a criterion. Due to the chemical structure of fats, the following are distinguished:

1. simple fats – these are the proper fats and waxes. For humans, fats are a high-energy material that provides twice as much energy as glucose. It is also a reserve material, therefore it is stored subcutaneously in the form of adipose tissue. Simple fats also have a thermal insulation and protective function.
2. compound fats – consist of fatty acids, alcohols and other compounds. They are divided into phospholipids and glycolipids. Complex fats are the building material of cell membranes. Moreover, they play the role of biologically active substances as steroid hormones and vitamins A, D, E and K. Complex fats are involved in digestive processes;
3. isoprene lipids – are the products of polymerization of molecules of a five-carbon unsaturated hydrocarbon called isoprene. There are steroids and carotenoids. Steroids are the starting material for the synthesis of steroid hormones, bile acids and vitamin D. On the other hand, carotenoids are involved in photosynthesis, are precursors of many compounds necessary for animals and act as antioxidants, i.e. compounds delaying the oxidation of various substances by free radicals;
4. derived fats – are saturated, monounsaturated, polyunsaturated fatty acids.

How to check how much fat is in our body? Check: Lipidogram – how much fat is in our body?

Fats and their role

There are saturated and unsaturated fats in the human body. Importantly, fats are found not only in animal products, but also in plant-based foods. The role of fats is to support the nervous system as well as the circulatory system. Surprisingly, fats lower cholesterol and protect internal organs, and are actively responsible for the absorption of vitamins A, D, E and K, as well as being their main source.

However, the main role of fats is the body’s need for energy. Thanks to fats, we can accumulate energy for proper functioning. Fat tissue under the skin is energy storage, but also protection against heat loss. Moreover, fats are a building material for cell membranes, and they increase the satiety of the food we eat, as well as reduce the secretion of acidic gastric juice and inhibit stomach cramps.

Can a high-fat diet be healthy? Read: A high-fat diet does not necessarily pose a risk of obesity

Digestion of fats in the human body

The digestion of fats is the breakdown of triglycerides into glycerol and fatty acids. Digestion begins in the stomach, which is influenced by the following enzymes: salivary and gastric lipase. However, the acidic environment of the stomach causes that the action of these enzymes is very limited and only a small part of the supplied fats are broken down.

Therefore, proper digestion of fats takes place in the duodenum and in the front part of the small intestine. In these organs, bile is secreted by the liver and stored in the gallbladder. When there is fat in the digested food, the gallbladder shrinks and bile is secreted, which emulsifies the fat, that is, it crushes it into tiny balls.

The pancreatic lipase then hydrolyzes the ester bonds of fats to form free fatty acids. In the small intestine, intestinal lipase acts, which breaks down fats into glycerol and fatty acids. Fatty acids with short and medium carbon chains and glycerol are absorbed into the blood and pass to the liver. On the other hand, fatty acids with a long carbon chain with cholesterol go to the tissues. The released fatty acids can be used as energy material or for the synthesis of new triglycerides.

Do you want to learn about the structure and functioning of the digestive system? Check it out: Human digestive system

Fats – the demand

The role of fats is very large, but it is worth remembering that what too much is not healthy. It is the same with fats. You should not eat too much of them, because they accumulate in our body and lead to excess weight. How much fat we can consume daily depends mainly on our physical activity, age, gender, and physiological condition. According to research, the need of an adult for fats is 3% of the total energy of food. The need for fats is greater in pregnant women and breastfeeding women. In the first case, the demand increases to 4,5%, and in the second, the woman needs 6% of the dietary fat requirement.

The right amount of fats in the diet will positively affect our health. However, if we eat too much of them, it can lead to obesity, and even to diabetes, coronary heart disease, hypertension or gallstone disease. What’s more, fats can promote the development of cancers of the colon, uterus or mammary glands. That is why it is so important that our diet is balanced and varied.

Fats – sources

We can divide fats into those of animal and vegetable origin. The group of vegetable fats includes those obtained from seeds and fruits of oil plants. Nuts are a valuable source of fats, for example. In contrast, animal fats come from the tissues of animals or their milk. We are talking not only about land animals, but also sea animals. Most of all, fish have a lot of valuable fat.

Sunflower, soybean or grape seed oils are an excellent source of fat that has a beneficial effect on our body. They reduce cholesterol levels. The fats in oily sea fish such as mackerel or herring are responsible for lowering cholesterol. If you have problems with triglycerides, it is worth consuming rapeseed oil or linseed oil, which reduce the concentration of these fats. Olive oils and rapeseed oil are also preferred sources of monounsaturated fatty acids.

You can also use fatty acid dietary supplements, such as OmegaMe Vege Health Labs – Omega 3 DHA fatty acids from sea algae.

The content of the medTvoiLokony website is intended to improve, not replace, the contact between the Website User and their doctor. The website is intended for informational and educational purposes only. Before following the specialist knowledge, in particular medical advice, contained on our Website, you must consult a doctor. The Administrator does not bear any consequences resulting from the use of information contained on the Website.