Linoleic fatty acid. High oleic oil: advantages over regular oil, benefits and harms, reviews. Linoleic acid: for skin

Acids are considered the most popular and very effective components of many cosmetics. They whiten the skin, even out the complexion, increase the firmness and elasticity of the skin, moisturize, smooth out wrinkles, rejuvenate, etc.

Acids- complex substances, which usually include hydrogen atoms that can be replaced by metal atoms and an acid residue.

Classification of acids:
1. According to oxygen content: oxygen-free, oxygen-containing;
2. By basicity - the number of acidic hydrogen atoms: monobasic, dibasic, tribasic, polybasic;
3. By strength: strong - dissociate almost completely, weak;
4. According to stability: stable, unstable;
5. By belonging to the classes of chemical compounds: inorganic, organic.
6. By volatility: volatile, non-volatile;
7. According to solubility in water: soluble, insoluble.

Organic acids that are used in cosmetology include fatty acids, fruit acids, etc.

The main fatty acids are palmitic, stearic, and linoleic acid.

Stearic acid- one of the most common fatty acids in nature, which is part of lipids in the form of glycerides, primarily triglycerides - fats of animal origin, the latter serve as an energy depot. The highest content of stearic acid is in animal fats: up to 30% - in lamb fat; up to 10% - in vegetable oils (palm oil). In the body, stearic acid is synthesized from palmitic acid.

Palmitic acid is part of the glycerides of most animal fats and vegetable oils: palm oil - 39-47%, cow's oil - 25%, soybean - 6.5%, lard - 30%. In animal organisms, palmitic acid is the end product of fatty acid synthesis.

With a lack of these acids in the body, the skin peels, nails become split, and hair becomes dull.

Stearic and palmitic acids are used in cosmetics, as emulsifiers, stabilizers and thickeners. In creams the content of these acids is 2-5%. The use of these acids in creams is very important for dry and chapped skin, to protect the skin from wind and frost. They relieve itching and irritation, increase elasticity and hydration. And stearic acid is an emollient, fixed in the stratum corneum, giving the skin smoothness and softness.

The largest group of acids used in cosmetics are AHA and BHA.

AHA acids– these alpha-hydroxy acids are commonly called fruit acids, as they were originally found in fruits: glycolic, lactic, malic, citric, almond.

TO VNA– beta-hydroxy acids include salicylic acid. The main difference between AHA and BHA is solubility; AHA acids are water-soluble, and BHA acids are fat-soluble. Cosmetic properties of AHA: promote exfoliation of the surface layer of the epidermis (weaken the bonds between keratin scales, accelerating the natural process of their separation), have a moisturizing effect, have an anti-inflammatory and antioxidant effect on the skin, stimulate the synthesis of collagen and glycosaminoglycans, and provide a pronounced rejuvenating effect.

Glycolic acid– hydroxyacetic acid, extracted from sugar cane and grapes. Accelerates the exfoliation of keratinized epidermal cells, easily absorbs water, and is used to adjust skin pH, deep cleanse the skin, reduce wrinkles and age spots. The glycolic acid molecule has the smallest molecular weight, easily penetrates the skin, stimulates fibroblasts, as a result of which collagenogenesis occurs, skin density and elasticity increases, and the depth of wrinkles decreases.

Mandelic acid– phenylglycolic acid, the simplest fatty aromatic hydroxy acid, is found in bitter almonds. It also belongs to the class of alpha hydroxy acids and has all the properties of fruit acids. The mandelic acid molecule is larger than the glycolic acid molecule, so it penetrates the skin more slowly, causing minimal irritation. It has a keratolytic effect, stimulates collagen synthesis and activates cellular renewal. It has a whitening effect, affects the pathogenesis of acne, and has a comedolytic and bactericidal effect. Reduces skin photosensitivity.

Apple acid– hydroxysuccinic acid is released from the pulp of unripe apples, has antioxidant, cleansing, moisturizing, anti-inflammatory and astringent properties, enhances cellular metabolism.

Lactic acid– alpha-hydroxypropionic acid, which is obtained from whey. It moisturizes the skin, normalizes the renewal process of epidermal cells, and enhances the synthesis of glycosaminoglycans and collagen. Helps strengthen the skin's lipid barrier by increasing the synthesis of linoleate-containing ceramides. The external manifestations of this process are an improvement in complexion, increased hydration, elasticity and firmness of the skin, and a decrease in the depth of wrinkles. It also normalizes the process of epithelization in the excretory ducts of the sebaceous glands and the mouths of hair follicles, reduces the density of comedones and pore sizes, therefore, it is also used in products for the care of problematic and oily skin.

Lemon acid found in lemons, limes, grapefruits and oranges. It has the highest molecular weight of all AHAs. It has a whitening, antipruritic, antiseptic, astringent effect, and is also added to cosmetics as a preservative, diluent and pH modifier.

Lactobionic and gluconolactonic acids- polyhydroxy acids, have a good moisturizing effect and do not cause skin irritation reactions.

Phytic acid- organic acid obtained from wheat seeds. Contained in the skins of legumes. Inactivates the enzyme tyrosinase and due to this has a whitening and pigmentation-preventing effect when used in a course. Has a good antioxidant and vascular strengthening effect.

Exfoliating acids also include salicylic and azelaic acid.

Salicylic acid– organic beta-hydroxy acid. It has antiseptic, antioxidant, keratolytic and anti-inflammatory properties. Already in small concentrations it prevents the growth of yeast and mold fungi and some bacteria. Used in cosmetics for oily and problem skin.

Azelaic acid– natural saturated dicarboxylic acid. A tyrosinase inhibitor inhibits RNA and DNA in melanocytes, thereby inhibiting the growth of abnormal melanocytes and reducing hyperpigmentation. It has antibacterial, anti-inflammatory and keratolytic effects. Used to treat acne, reduce hyperfunction of the sebaceous glands and lighten age spots.

Hyaluronic acid– non-sulfonated glycosaminoglycan, a natural component of connective, epithelial and nervous tissue, a key component of the extracellular matrix, found in many biological fluids (saliva, synovial fluid). The body of a 70 kg person on average contains about 15 grams of hyaluronic acid. It binds water in the intercellular spaces, thereby increasing tissue resistance to compression. One hyaluronic acid molecule binds about 500 water molecules. It is involved in the transport and distribution of water in tissues, determines the barrier and protective functions of the intercellular space. The hyaluronic acid molecule is very large and cannot penetrate into the deeper layers of the skin. But even when used externally, this acid gives very good results; when applied, it forms a thin film on the skin that draws moisture from the air. Consequently, hyaluronic acid is included in sunscreen and anti-aging products intended for dry and dehydrated skin.

When using cosmetics with acids, you must follow the rules to avoid side effects:
• mandatory consultation with a specialist (cosmetologist, dermatologist);
• use sunscreen SPF - at least 15;
• Avoid exposure to the sun, and on sunny days wear a wide-brimmed hat and long sleeves;
• for people with sensitive skin, test cosmetics on small areas of the skin, and if irritation occurs, it is better to refuse further use;
• Use the acid concentration appropriate for the specific age (do not use for children).

Pharmacological group: omega-6 fatty acids; essential fatty acids; anti-inflammatory drugs; anti-acne drugs; fat burners; antitumor drugs.
IUPAC name: (9Z, 12Z) - 9,12 - octadecadienoic acid
Molecular Formula: C 18 H 32 O 2
Molar mass: 280.45 g mol-1
Appearance: colorless oil
Linoleic acid is an unsaturated omega-6 fatty acid. At room temperature, linoleic acid is a colorless liquid. Chemically, linoleic acid is a carboxylic acid with an 18-carbon chain and two cis double bonds. The first double bond is located on the sixth carbon from the methyl end.
Linoleic acid belongs to one of two families of essential fatty acids. The body cannot synthesize linoleic acid from other food components.
The word "linoleic" comes from the Greek word Linon (flax). Oleic means “relating to or derived from olive oil” or “related to oleic acid” because when the omega-6 double bond is saturated, oleic acid is produced.
Some medical research suggests that excessive levels of certain omega-6 fatty acids, associated with certain omega-3 fatty acids in combination with exogenous toxins, may have negative health effects.

Linoleic acid in physiology

Linoleic acid is a polyunsaturated fatty acid used in the biosynthesis and therefore of some prostaglandins. It is found in the lipids of cell membranes. Linoleic acid is present in large quantities in many vegetable oils, including poppy seed, safflower, sunflower and corn oils.
Linoleic acid is an essential fatty acid that must be consumed through food. In rats, due to a deficiency of linoleate in the diet, peeling skin, hair loss and poor wound healing are observed. However, in a normal diet, linoleic acid deficiency is extremely rare.
Cockroaches secrete linoleic and oleic acids when dying, which serves as a signal to other cockroaches, protecting them from entering the danger zone. The same mechanism works in ants and bees, which produce oleic acid after death.

Metabolism and eicosanoids

The first step in linoleic acid metabolism is delta-6 desaturase, which converts linoleic acid to gamma-linolenic acid.
There is evidence that infants cannot produce delta-6 desaturase on their own, so infants must obtain it from breast milk. Research shows breastfed infants have higher concentrations of gamma-linolenic acid than formula-fed infants, while formula-fed infants have elevated concentrations of linoleic acid.
Gamma-linoleic acid is converted to dihomo-gamma-linolenic acid, which in turn is converted to arachidonic acid (AA). AA can be converted into a group of metabolites called eicosanoids, which are a class of paracrine hormones. There are three types of eicosanoids: prostaglandins, thromboxanes and leukotrienes. Eicosanoids derived from AA are generally pathogenic. For example, the AA-derived thrombaxane and leukotriene-B4 are vasoconstrictor eicosanoids. Oxidized products of linoleic acid metabolism, such as 9-hydroxyoctadecanoic acid and 13-hydroxyoctadecanoic acid, also activate TRPV1, the capsaicin receptor, and may therefore play an important role in hyperalgesia and allodynia.
Increased intake of certain omega-3 fatty acids while decreasing intake of omega-6 fatty acids reduces inflammation due to reduced production of these eicosanoids.
One study that followed two groups of myocardial infarction survivors found that “in the experimental group, alpha-linolenic acid concentrations increased by 68% and linoleic acid concentrations decreased by 7%...survivors of the first myocardial infarction, which was prescribed a Mediterranean diet with increased levels of alpha-linolenic acid had markedly reduced relapse rates, risk of cardiovascular events, and overall risk of mortality."

Usage

Industrial use

Linoleic acid is used in creating quick-drying oils, oil paints and varnishes. Linoleic acid easily reacts with oxygen in the air, which leads to the formation of cross-links and the formation of a stable film.
When linoleic acid is reduced, linoleyl alcohol is formed. Linoleic acid is a surfactant with a critical micelle concentration of 1.5 x 10−4 M @ pH 7.5.
Linoleic acid is gaining popularity in the beauty products industry due to its positive effects on the skin. Research indicates that linoleic acid has anti-inflammatory properties, fights acne, and helps maintain skin moisture when applied topically.

Use in research

Linoleic acid can be used to study the antioxidant effect of natural phenols. Experiments on 2,2"-azobis(2-amidinopropane)-induced linoleic acid oxidation with various combinations of phenolics indicate that binary mixtures can have either a synergistic antioxidant effect or an antagonistic effect.
Linoleic acid may be associated with obesity because it may promote overeating and damage to the arcuate nucleus in the hypothalamus of the brain.

Products containing linoleic acid

Saltweed oil 75%
Safflower oil 74.62%
Evening primrose oil 73%
Poppy oil 70%
Grapeseed oil 69.6%
Sunflower oil 65.7%
Hemp oil 60%
Corn oil 59%
Wheat germ oil 55%
Cottonseed oil 54%
Soybean oil 51%
Walnut oil 51%
Sesame oil 45%
Rice bran oil 39%
Argan oil 37%
Pistachio oil 32.7%
Peanut butter 32%
Almonds 24%
Rapeseed oil 21%
Chicken fat 18-23%
Egg yolk 16%
Flaxseed oil 15%
Lard 10%
Olive oil 10% (3.5 - 21%)
Palm oil 10%
Cocoa butter 3%
Macadamia oil 2%
Butter 2%
Coconut oil 2%

The opinion that existed even in the first decade of our millennium that any oils are categorically contraindicated for oily, and especially problem skin, has now undergone a significant change or, more precisely, has become completely opposite, declaring oils for oily skin almost a panacea. Although everything here, of course, is purely individual and far from so simple. There has never been a universal panacea for everyone.

Followers of the above theory argue that the reason for pores clogged with too thick sebaceous secretion lies in the chemical, fatty acid composition of this sebaceous secretion, which contains too many saturated and monosaturated fatty acids and too little polyunsaturated linoleic acid.

It is linoleic acid that is responsible for the skin’s ability to properly renew and cleanse itself. Its deficiency leads to strong sebaceous secretion (hyperfunction of the sebaceous glands) and peeling of the skin (hyperkeratosis), which clog the flow of the sebaceous glands, which becomes the cause of acne and pimples. The use of linoleic acid in the care of oily and problem skin gives a good effect on both teenage and adult pimples and acne.

The most beneficial vegetable oils for oily and problem skin that contain linoleic acid are:

iHerb),
• blackcurrant oil,
• borage oil,
• kukui oil,
iHerb),
• kiwi oil,
• raspberry oil,
• Spanish sage (chia) oil.

Linoleic acid is not produced by the body and oils containing it are recommended to be used not only externally, but also internally. Most often, evening primrose oil is chosen for internal use. It is worth noting here that this oil is classified as an estrogenic phytohormone, and its uncontrolled use can cause serious hormonal imbalance.

The most affordable for us is rosehip oil, which is sold in almost every pharmacy. If you decide to experiment with it, make sure that your oil is sufficiently purified and does not stain the skin.

Since rosehip oil is an unstable oil, do not heat it and store it in the refrigerator. To increase the shelf life of the oil, add vitamin E or some much more stable oil, such as jojoba oil.

In previous times, rosehip oil was classified as a comedogenic oil and was not recommended for use in its pure form, and these recommendations should not be neglected at all. Most often, this oil is recommended to be applied in a ratio of 10% to the total mass of the cosmetic product. Although you can put more of it in home masks, provided that the product does not remain on the skin for a long time.

In the following recipes, rosehip oil is completely replaceable with evening primrose oil or other oils from the list above, including their mixtures.

Oil mask

• 1 egg yolk,
• 1 teaspoon glycerin (buy on iHerb),
• 1/2 teaspoon rosehip oil,
• 5-7 drops of lavender essential oil,
• 5-7 drops of tea tree essential oil.

Grind the yolk with rosehip oil, add essential oils and glycerin.

Apply for 10-15 minutes, then rinse thoroughly. If your skin requires cream, give it to it, but if your skin does not need cream, then you should not overload it.

Well: every 3-5 days for 12-14 weeks.

After five to six weeks, results should appear showing whether oil care is suitable for your skin.

Serum gel

• 1 bottle of Blefarogel 2 (sold in a pharmacy, contains sulfur, hyaluronic acid and aloe vera gel),
• 1/8-1/3 teaspoon soy or sunflower lecithin - not necessary, but recommended (Iherb),
• 1/2 teaspoon glycerin,
• 1/3 teaspoon rosehip oil,
• 10-15 drops of lavender essential oil,
• 10-15 drops of tea tree essential oil.

To prepare the serum, use clean and dry objects that have been previously treated with chlorhexidine or wiped with alcohol wipes for injection. Put disposable gloves on your hands and also treat them with an antiseptic.

Decide in advance how you will store the finished product. A bottle with a dispenser is best suited for this. Disinfect it properly too.

Mix Blepharogel with glycerin and rosehip oil. Mix everything vigorously or, even better, beat with a mini mixer, gradually adding lecithin and achieving the consistency you need. Then, continuing to stir, add essential oils.

Use as a serum, applying a thin layer under basic care, or as a mask, applying a medium layer to the skin for 30-40 minutes every day or every other day.

Store in the refrigerator for no more than a month and make sure that no water gets inside.

I am glad to welcome you to my website Youth of face, body and soul. Today on the agenda in the section Vitamins for youth And Benefit in everything composition of vegetable oil. What's in composition of vegetable oil includes a large list of various vitamins: E, C and micro- and macroelements (potassium, sodium, calcium, iron...) everyone knows or at least guesses. Nowadays it has become very fashionable to use the following terms in relation to fats: Omega 3,6,9 fatty acids. Few people know the difference between these three numbers, but many strive to eat these Omegas more often. The common belief is that all Omegas live in fatty sea fish and olive oil. But is olive oil really the best and only source of Omega 3, 6, 9? fatty acids. I present to your attention the rating of the usefulness of vegetable oil, the composition of which was analyzed from the point of view of its fatty acid content.

First, a little theory. Have fun exploring the differences in structure fatty acids, their molecules, bonds, relationships with each other, only a true chemist can, so take my word for it: unsaturated fatty acid have a positive effect on the structures of the walls of blood vessels, improve them, ensure the functioning of the immune system at an optimal level, do not allow cholesterol to settle on the walls of blood vessels and accumulate in the body, actively participate in the synthesis of various hormones and much more, keeping us youthful, healthy and beautiful for decades. Normal metabolism in the body is ensured, among other things, by unsaturated fatty acids, and the membrane of any cell without them will not form at all.

Now let’s remember three concepts in the composition of vegetable oil:

• Omega-9 fatty acids – oleic acid.
• Omega-6 fatty acids are linoleic acid and gamma-linolenic acid.
• Omega-3 fatty acids – alpha-linolenic acid.

Omega-9 fatty acids.

Oleic acid lowers total cholesterol levels, while increasing the level of “good” cholesterol and reducing the level of “bad” cholesterol in the blood), promotes the production of antioxidants. Prevents atherosclerosis, thrombosis, aging. If the composition of vegetable oil contains a lot of oleic acid, then fat metabolism is activated (helping to lose weight), the barrier functions of the epidermis are restored, and more intense moisture retention in the skin occurs. Oils are well absorbed into the skin and actively promote the penetration of other active components into its stratum corneum.

Vegetable oils, which contain a lot of oleic acid, oxidize less and remain stable even at high temperatures. Therefore, they can be used for frying, stewing and canning. According to statistics, residents of the Mediterranean region who constantly consume olive oil and avocados, nuts and olives themselves are much less likely to suffer from cardiovascular diseases, diabetes and cancer.

• Almond - 83%
• Olive – 81%
• Apricot - 39-70%

For comparison, sunflower oil contains 24-40%.

Omega-6 fatty acids.

They are part of cell membranes and regulate the level of various cholesterols in the blood. They treat multiple sclerosis, diabetes, arthritis, skin diseases, nervous diseases, protecting nerve fibers, cope with premenstrual syndrome, maintain smoothness and elasticity of the skin, strength of nails and hair. If they are deficient in the body, the metabolism of fats in tissues is disrupted (then you will not be able to lose weight), and the activity of intercellular membranes is disrupted. Also a consequence of a lack of Omega-6 are liver diseases, dermatitis, vascular atherosclerosis, and the risk of cardiovascular diseases increases. The synthesis of other unsaturated fatty acids depends on the presence of linoleic acid. If it does not exist, then their synthesis will stop. Interestingly, when consuming carbohydrates, the body's need for foods containing unsaturated fatty acids increases.

• safflower – 56 – 84%
• nut – 58 – 78%
• sunflower – 46 – 72%
• corn - 41-48

For comparison, in olive oil it is 15%.

Omega-3 fatty acids.

Omega 3 is vital for normal brain function. With their help, there is an influx of energy necessary to transmit signal impulses from cell to cell. Maintaining mental abilities at a decent level and the ability to retain information in memory, actively use your memory - all this is impossible without alpha-linolenic acid. Omega-3s also have protective and anti-inflammatory functions. They improve the functioning of the brain, heart, eyes, lower cholesterol levels, affect joint health, and are excellent antioxidants. They improve the condition of eczema, asthma, allergies, depression and nervous disorders, diabetes, hyperactivity in children, arthrosis, cancer...

• flaxseed - 44%
• cotton - 44%
• camelina – 38%
• cedar - 28%

For comparison - in olive oil - 0%

Results.

Omega-3 and Omega-6 have one very important drawback - when fats are heated and interact with air, they actively oxidize. A large number of toxic oxides and free radicals are formed, which negatively affect the entire body. Therefore, if the composition of vegetable oil is rich in Omega-3 and Omega-6 - fry You can't use this oil. And it should be stored in a dark, cool place in a closed container.

I just don’t understand why in all the stores bottles of sunflower oil are on shelves under light bulbs! Pay attention to expiration dates! Fry only in olive oil!

The adult human body can synthesize only Omega-9 itself. And Omega-3 and Omega-6 can only be supplied with food.

Vegetable oils, the composition of which includes all Omegas.

Omega-9/Omega-6/Omega-3.

• Grapeseed oil 25/70/1
• Kedrovoe 36/ 38/18-28
• Hemp 6-16/65/15-20
• Sesame 35-48/37-44/45-57
• Linen 13-29/15-30/44
• Sea buckthorn 23-42/32-36/14-27
• Nut 9-15/58-78/3-15
• Sunflower 24-40/46-72/1
• Ryzhikovoe 27/14-45/20-38
• Soybean oil 20-30/44-60/5-14
• Cotton 30-35/42-44/34-44

Since catching the balance of consumption of the necessary fatty acids not very simple, the best solution is variety. Don't stop at one oil, try others! Fans of olive oil, please note that it contains little Omega-6, and no Omega-3, which the body cannot synthesize itself. Diversify your diet!

The consumption rate of vegetable fat is at least 30 grams per day.

P.S. If you abuse Omegas, you can earn yourself:

• high blood pressure
• vasoconstriction
• decreased immunity
• activation of inflammatory processes

Yes, and I also want to clarify, the article discussed composition of vegetable oil, which can be consumed orally. There are more valuable oil compositions that can only be applied to the skin.

One of the main functions of the skin is barrier. The protective layer of the skin consists of keratinized epidermal cells, fastened together by special bridges (desmosomes), forming intercellular gaps. The space between them is filled with a lipid layer.

Penetration of various substances through the stratum corneum, both water- and fat-soluble, is possible only in two ways: through the intercellular spaces or through the ducts of the sebaceous glands (transfollicular path). But the main route is through intercellular spaces.

Responsible for the permeability of the stratum corneum of the skin lipid barrier is a clearly structured mass consisting mainly of lipids and proteins, which represent the previously mentioned desmosomes.

The chemical composition of intercellular lipids is unique and absolutely does not correspond to the composition of sebum lipids. Lipids in the stratum corneum are synthesized in keratinocytes - epithelial cells - as they mature. At the level of the transition of the granular layer to the stratum corneum, the precursors of these lipids are released into the intercellular space, where, with the participation of enzymes, the assembly of the lipid layers that make up the barrier begins.

The lipids of the stratum corneum are organized into extended and continuous layers, each of which represents a classic biological membrane (for more details, see the blog). The layers are superimposed on each other, and the role of the layer between them is played by water, which is constantly in motion. Its molecules move and, reaching the very top layer, evaporate. Evaporation occurs slowly with the barrier intact. The composition of the lipid barrier is represented by 3 types of lipids (fats and fat-like substances):

• ceramides are substances of natural origin, solid or waxy substances of lipid nature;
• cholesterol is a natural fatty alcohol that plays an important role in the life of the body, is part of all cell membranes in tissues and organs, is a precursor of corticosteroid and sex hormones, bile acids, vitamin D, etc.;
• free fatty acids.

Let's talk about the latter.

In the lipid barrier, fatty acids are present both as part of ceramides and in the free state. An important characteristic of fatty acids is saturation, i.e. presence of double bonds in a molecule. Fatty acids containing two or more double bonds are called polyunsaturated, and the more such acids there are in the oil, the more liquid it is.

Saturated – fatty acids without double bonds, so they have a solid consistency. They are not subject to rapid oxidation, contribute to the hardening of the lipid layer, therefore they remain on the surface, acting as emollients (softening agents). Thus, the quantity and quality of saturated fatty acids determine the viscosity of the fat medium.

It’s difficult to overestimate the role vitamin F, which is a complex of unsaturated fatty acids: linoleic (Omega-6), linolenic (Omega-3) and arachidonic (Omega-6) in the “work” of our skin. Shortagevitamin F is expressed in peeling, dryness and redness of the skin. The uniqueness of these fatty acids is that, although they are not synthesized in the body, they are involved in many metabolic processes. In particular linoleic acid necessary for the formation of a proper epidermal barrier, therefore When it is deficient, the skin becomes dry and flaky. Linoleic, linolenic and arachidonic acids are substances for the production of hormone-like substances that regulate inflammatory processes - prostaglandins, therefore, with a lack of these acids (especially linolenic acid), the skin becomes prone to inflammation.

Feeding the skin with vitamin F from the inside (inclusion in the diet) and outside (applied to the skin) can correct problems such as dryness, flaking of the skin, and its tendency to inflammation [1].

The studies show that a mixture of lipids, which form the basis of the lipid barrier of the skin, is much more effective in maintaining the moisture-holding capacity of the skin and restoring the lipid barrier in case of external damage than each of the components of the mixture separately or a mixture of lipids, albeit similar in composition and properties, but still different from them. Moreover, the greatest effectiveness of the action of a mixture of lipids is observed in their natural proportion, characteristic of normal healthy skin, in contrast to a mixture of the same components in non-optimal proportions.

The grouping is mainly based on the characteristics of fatty acids. Here we consider the groups of the most basic acids: oleic, palmitic, linoleic and linolenic. Of which linolenic acids are considered as an additive, and the rest form the basis of the formulation. Of course, in your recipes you can focus on a certain group of acids - oleic or linolenic.

“Photostability” and oxidation stability

The resistance of fats and oils to oxidation is determined by the location, geometric configuration and number of double bonds: for oxidation under normal conditions, the presence of a double bond is necessary. It has been established that the higher the degree of unsaturation of a fatty acid, the lower its apparent oxidative stability. For linolenic acid, which has three double bonds, the relative rate of oxidation is twice as high as for linoleic acid, which has two double bonds. Oleic acid, which has one double bond (monounsaturated), is the most stable of the three fatty acids considered.

Note for some oils - » do not use in the sun" refers to oils with a high proportion of polyunsaturated fatty acids. Light and heat can accelerate the process of oxidation and decomposition of oils with polyunsaturated fatty acids on the surface and inside the skin; toxic breakdown products can damage cell membranes and lead to the formation of age spots, provoke sun allergies, and skin irritations. Oils suitable for use in sunscreens and for use in the sun are listed below according to the designation “Sun exposure”, which means their possible use in cosmetic products, when applied, can be exposed to intense sunlight for a long time (extended sun exposure). sun, beach, etc.).

It has been proven that, from a cosmetic point of view, day care products (with a high content of vegetable oils susceptible to oxidation) are better stabilized by the addition of base lipids, such as jojoba, marula, and meadowfoam oils. These oils extend the shelf life of polyunsaturated fatty acids and allow the creation of compositions that do not cause skin irritation. Very unstable oils are best used only in night products to minimize oxidative stress on the skin.

Brief overview of different groups of vegetable oils

1. Stabilizing base oils: group B-0 (accounts for 20-50% of the mixture):

The most resistant to oxidation are oils that contain large amounts of saturated fatty acids.

• Thanks to its composition, jojoba oil is universal, very stable to oxidation, is not affected by bacteria, does not leave a greasy feeling, and thus creates a very long-lasting protective effect. It can be used as a base or as an additive to an oil mixture.
• Meadowfoam oil can essentially be described as jojoba
• Squalane (vegetable) usually obtained from olive oil is a stable emollient with good spreadability and low viscosity. Can be used as a base or as an additive to an oil mixture
• Marula oil is extremely resistant to oxidation
• Sesame oil contains a very strong antioxidant, sesamol, which is why it is called “sesame oil.”
• Capryl/caprylic triglycerides are a mixture of capric and caprylic acids that are obtained from coconut or palm oil. An emollient that does not cause irritation, has good spreadability and high oxidative stability.

2. Caring base oils: oils of groups B-1, B - 2, B-3 (50-70% of the mixture)

• Group B-1 - oils with dominant oleic acid, stable to oxidation, protect the skin, light or slightly oily skin: apricot kernels, avocado, hazelnut, camellia japonica, macadamia, almond, olive, sunflower high oleic, buriti, safflower, avocado, Brazil nut oil, plum kernels, peach kernels, moringa , papaya.
• Group B-2 - oils with a balanced ratio of mono- and polyunsaturated acids. Monovariants can be used: argan, baobab, rice bran oil, sesame oil, cherry pits.
• Group B-3 - oils with dominant linoleic acid, are absorbed more easily and provide less fat: amaranth, safflower, poppy seed oil, soybean oil, sunflower, grape seed, walnut oil, wheat germ oil, green coffee, corn, hemp, pumpkin, cedar, amla oil extract.

3. Active oils: oils of groups A1 and A2 (up to 10% of the mixture)

This group includes oils with a high proportion of polyunsaturated, partly rare, fatty acids. Such oils are very prone to oxidation, but you should not refuse them, because... They are the ones who exhibit pronounced cosmetic properties - restoring and activating. Depending on the dominant fatty acid, these oils belong to groups A-1, A-2 and A-3. They are usually taken in a small safe dosage, about 5-10%, and are recommended to be used at night or on days when you do not go outside.

• Group A-1 – oils with a predominance of alpha-linolenic acid(is a precursor of prostaglandins and can increase the level of prostaglandin E in the body, helps retain moisture in the skin and hair, is recommended for the care of dry skin, has anti-inflammatory properties, and is recommended for people suffering from skin diseases): hemp oil, elderberry oil, oil cranberry seeds, sacha-inchi, sea buckthorn oil, flaxseed, camelina, mustard, soybean, rosehip oil, strawberry seed oil, raspberry seed oil.
• Group A-2 – oils with a predominance of gamma-linolenic acid(substances formed from gamma-linolenic acid have an anti-inflammatory effect, strengthens the structure of cell membranes, recommended for dry skin with impaired barrier properties): borage, black currant seeds, evening primrose, cranberry seed oil, neem.
• Group A-3 – oils containing specific and rare acids: pomegranate seed oil, sea buckthorn oil, black cumin oil, laurel, tamanu.

4. Vegetable butters: oils group PB-1 and PB-2 (partially belong to group B-0), (up to 10-30%).

• Group PB-1 – oils with a high content of saturated long-chain fatty acids and with a solid consistency at room temperature. The most famous among them: shea, mango, cupuaçu. They generally have a higher proportion of non-saponifiables. Protect , have a greasy tactile sensation and are absorbed slowly but deeply into the skin. They can also be used for their sensory properties, i.e. they add fullness to the emulsion and make it pleasant to apply: cocoa butter, cupuaçu, mango, shea butter, palm oil.
• G group PB-2. This group includes oils that have a high content of saturated acids with short and medium chains. They distribute well, give a light, non-greasy feeling in emulsions and even out the tactile sensations in the emulsion. Oils of this group penetrate quickly, but only superficially into the stratum corneum of the skin: coconut oil, Monoi de Tahiti, babbasu.

List of used literature

1. Based on “New Cosmetology” by Margolin, Hernandez.
2. M. T. Houtsmuller, Progress in Lipid Reseach, 20,219 (1981)
3. Mao-Quing, K. R. Feingold, P. M. Elias, Arch. Dermatol., 129,728-738 (1993)
4. “Combination of vegetable oils (Olionatura ®)” Translation of the work by H. Käser “Öle kombinieren:Kombinationsstrategien”