The heroes of our story have several names. Sterols, steroidal alcohols, sterols - these are one of the most important chemicals for a living organism. The most famous human sterol is cholesterol, which is the precursor of fat-soluble vitamins, steroid hormones. We know of plant sterols and bioadditives. People take them in a complex of vitamins of groups A, D, E and K. Next, we will tell as much as possible about sterols and their types. Why are sterols important to humans? How to recognize their excess / deficiency in the body? What products contain these elements? Read about all this below.
What is it?
Sterols are cyclic macromolecular alcohols that will belong to the class of lipids (fats). Their parts are able to dissolve in a fat-like and aqueous medium, and the elements themselves are resistant to saponification - hydrolysis with the formation of alcohol and acid. As for the structure of sterols, the basis of the whole group is steran-3-ol.
The cell structure, a number of vital body processes, directly depend on them. Responsible for the fluidity of cell membranes, the protection of plants from heat stroke.
Interestingly, the synthesis (production) of elements is carried out by all eukaryotes - living beings whose cells have nuclei. They will be people, and animals, and plants, and mushrooms. But prokaryotes (bacteria that do not have nuclei) do not produce them.
Sterols are an important class of steroids. Their concentration in the tissues of animals and plants is significant. Consider an example of vertebrates:
- 10% adrenal gland weight.
- 2% of the weight of the nervous tissue.
- 0.2% of the liver weight.
- Concentrated in the brain cells in the form of cholesterol.
- High content in the membranes of all cells.
Sterol chromatography is gas-liquid. This is the name of the method of separation, analysis of various substances, the study of their physical or chemical properties.
Having defined sterols, we will move on.
Substance groups
All sterols can be divided into the following large categories:
- Zoosterols. Contained in animal cells. The main role here is played by the cholesterol necessary for the synthesis of vitamin D.
- Phytosterols. Available in plant cells.
- Sterin mushrooms.
- Sterols bacteria.
Varieties of elements
The group is represented in a wide variety. The following are the types of sterols:
- Cholesterol. It acts as the main sterol in the body of vertebrates.
- Ergosterol (the second name is mycosterol) is an element that plays an important role in the life cycle of fungi. However, it is useful for humans.
- Stigmasterol. It can be found in plants.
- Sitosterol is another styrene of plants that is responsible for their embryonic development.
- Styrene surrogates are characteristic only for certain types of bacteria whose development occurs under extreme conditions.
Value for the human body
Why are sterols so important for the human body? Substances perform a number of important functions:
- In the form of salts of bile acids contribute to good digestion.
- Maintain elasticity, the structure of the outer walls of cell membranes.
- In the form of cholesterol, they are precursors of vitamin D.
- The basis for the creation of vitamin A, E complexes in plant organisms.
- Reduce bad cholesterol.
- They are natural antioxidants.
The main tasks of the elements
Four main tasks of sterols can be distinguished. It:
- Cell communication. These particles exchange signals, pulses, information. This is necessary for the proper functioning of tissues, organs, the body as a whole. Sterols are designed to transmit signals from cell to cell. They can also provide information from the external environment, which helps the cell to regulate its growth and development. Therefore, one of the names of sterols is "secondary messengers."
- Fat soluble vitamins. They will be synthesized by the body from sterols. Note that vitamin A is useful for vision, healthy skin, D - for bone structure, immunity, E is an antioxidant that protects damaged cell mass, K - is vital for normal blood coagulation.
- The integrity of cell membranes. As we have already noted, sterols (in humans this is cholesterol) maintain the state of the cell membrane. So called external shells that protect the particle. Like the skin on our body. Sterols are responsible for the integrity of this lipid double layer, its resistance to temperature extremes.
- In the human body, they act like steroid hormones. For example, cortisol - stress hormone, estrogen, testosterone - female and male sex hormones, respectively, aldosterone regulates the mineral balance.
Food Sources of Elements
What else can you say about sterols and steroids? Their highest concentration is observed in foods that are rich in cholesterol. The most useful among them are chicken eggs (in particular, yolks), sea shrimp.
It should be noted that plant foods are richer in sterols than animal products. For example, 100 g of corn oil will contain 700 mg of sterol. And in 100 g of oil obtained from wheat germ, there are as many as 13-17 g of the element! While for the main products of animal origin, the maximum will be 500 mg of sterol per 100 g of food.
The richest in sterol are nuts, legumes, vegetable oils, seeds. According to the researchers, the leaves of famous rapeseed consist of plant sterol at 72%! Surprisingly, sterols can also be found in chloroplasts, pollen, shoots of some of the "green inhabitants" of the planet.
Introducing the richest sterols products:
- Brains (more than 2000 mg per 100 g of product).
- Corn oil (600-1000 mg).
- Quail egg (600 mg).
- Chicken Egg (570 mg).
- Liver of cod fish (520 mg).
- Cow's milk.
- Flaxseed oil.
- Cottonseed oil.
- Beef kidneys.
- Rapeseed oil.
- Sunflower table oil.
- Soybean oil.
- Carp meat.
- Beef liver.
- Peanut butter.
- Olive seed oil.
- Butter in braces.
- Beef meat.
- Pork liver.
- Sour cream (not less than 30% fat content).
- Lard.
- Veal.
- Low-fat varieties of pork.
- Cottage cheese.
- Pike dishes.
- Mutton.
- Broiler chicken.
- Sour-milk products (ordinary kefir is especially valuable).
The list is presented from products with the highest concentration of sterols to food with a lower content.
Biologists note that plant sterols (phytosterols) are more easily absorbed by the human body than zoosterols ("brothers" of animal origin). This is due to the fact that the former are more vulnerable to gastric juice.
The daily need of the human body for an element
These indicators are individual - they depend on the health of a particular person:
- Healthy people are advised to consume about 3 g of phytosterols (of plant origin) and not more than 300 mg of zoosterols (of animal origin) in the form of cholesterol every day.
- For people with high "bad" cholesterol, suffering from cardiac, vascular pathologies, with a risk of developing atherosclerosis, the norm is calculated individually by a nutritionist.
- In the direction of increase, the specialist is reviewing the daily norm for a patient with a weakened immune system, general poor health, decreased libido, and a diagnosed deficiency of vitamins A, D, E, K.
- The norm rises for children with rickets, weakened immunity, as well as for pregnant and lactating women.
- Actively working people - both physically and mentally - should increase the amount of foods rich in sterols in their diet.
- If a person is at risk for a possible heart attack or stroke, he needs to increase the amount of sterol in his diet - but only of plant origin.
What indicates a deficiency of an element in the body?
There is no specific sign that would clearly indicate that the human body lacks sterol. But experts identify a number of conditions, which together will be a similar signal:
- Not the best condition of hair, nails, skin.
- Weakened immunity.
- Constant feeling of general weakness, loss of strength.
- Depletion of the nervous system.
- Hormonal problems.
- The appearance of early signs of aging.
- Various sexual disorders.
- The development of atherosclerosis, frequent mood changes will speak about the lack of sterols of plant origin.
What does overabundance of an element in the body indicate?
Not everything is good, which is a lot. An excess of sterols in the body is fraught with the following consequences for a person:
- Improper coagulation of blood mass.
- Problems with the functioning of the liver, spleen.
- The development of cholelithiasis.
- High blood pressure.
- An excess of cholesterol in the body is reflected in the development of atherosclerosis.
So, products rich in sterol are an integral component of the human diet, ensuring their good health and well-being. However, they should be consumed rationally, in consultation with a nutritionist, giving preference to elements of plant origin.