Can cosmetic ingredients to penetrate the epidermis and, if so, how they do it? Understand.
Maya Lazareva, editor of 1nep.ru, columnist Flacon, author articles for the beauty gloss, the leading popular science telegram channel about skin care BeautyByMaya:
— When I became a beauty editor, my understanding of how the skin and how the makeup it’s quite peculiar. Thought cosmetics or immediately enters the bloodstream through the skin — then it is at least a cure, or she is lying dead layer and does nothing.
It seems like this happens not only with me. The beauty community is like divided into two camps. First I believe that the modern creams are not able to penetrate the epidermis, and all statements to the contrary — the machinations of marketers and the second is that new technologies can do everything!
Try to figure out whether after all the cream to penetrate the skin and how deep? Who to believe, where to go? And most importantly, what cream eventually take?)))
The law in Europe and Russia says that all cosmetics, if it is not a cure, has the right to work only at the level of the upper layers of the epidermis (the stratum corneum), without changing the characteristics and functioning of the skin and its elements.
“Perfume and cosmetic products (PKP) — a substance or mixture of substances designed to be applied directly on the external cover of a human (skin, hair, nails, lips and external genital organs) or on teeth and mucous membranes of the mouth with the sole or main purpose of cleansing, change their appearance, give a pleasant smell, and/or correcting body odors and/or protecting and/or maintaining in good condition and/or care for them.” (Technical regulations TC 009/2011)
You would think that with professional makeup everything is clearer, and there sure everything gets to the right place. But this is not true. In the technical regulations on cosmetic products, the wording, and that it is rather vague.
“Cosmetics — perfume and cosmetic products intended for use by legal entities and individual entrepreneurs in the provision of hairdressing and/or beauty services” — that is professional in the sense of law is becoming any beauty, if it uses a specialist. (Technical regulations TC 009/2011).
Although we have already taken. Still a large number of funds can work in the deeper layers of the epidermis and sometimes in the dermis. Just manufacturers and distributors (if they are law-abiding and do not want to run into penalties) don’t talk about it.
A bit of theory
If you’re anything interested in beauty, then the information that one of the main functions of the skin barrier — you somehow caught.
But this still does not mean that the skin is impervious. For example, without any additional assistance from technologists through the stratum corneum fairly easily penetrate substances with molecular weight less than 500 daltons. And you many of these substances know and use is retinoic acid and other forms of vitamin A, vitamin E, resveratrol, glycolic and salicylic acid, AHA, sodium hyaluronate (low molecular weight hyaluronic acid), caffeine, Niacinamide, and a sufficiently large number of peptides (mostly small).
If the skin is not in the best condition, for example, is too dry or oily, and barrier function worsens.
If you have dry skin lipid layer, formed holes, respectively, inside can penetrate substances and large molecular weight than 500 Yes (but not much).
Oily skin enlarged pores and active sebaceous glands that opens the doors to many of the ingredients, as fat-soluble substances penetrate better always (and cosmetic chemists take advantage of this, pridelava to more “major” parts of fat-soluble molecules to enhance their penetration).
- Substances with a molecular weight of at least 500 pretty easily penetrate the skin without help
- Impaired barrier function of the skin improves its permeability
But exactly where the ingredients go?
Most of the ingredients can penetrate from the surface of the Horny layer in depth of the epidermis. Small peptides, AHA acids, vitamins, for example. Other slip down to the dermis and hypodermis in different ways — it depends on the size of the molecule, to a disturbed lipid layer, lipid-soluble or water-soluble one or the other ingredient.
For example, some forms of retinol partially penetrate into the dermis and essential oils and deeper.
But although the vast majority of cosmetic ingredients penetrates only into the epidermis (recall that in the deeper layers of the epidermis are living cells), they are able to give effect in much deeper layers. The isolated impact on the skin cells is possible only in laboratory conditions, in life we always get a response from the immune and nervous systems, and that this response provides the change in the characteristics directly to the dermis and epidermis.
Sizes of cosmetic ingredients
- Glycolic acid 76 Da
- Niacinamide 137 Da
- Resveratrol 228 Da
- Retinol 287 Da
- Caffeine 194 Da
- Tocopherol 430 Da
- Vitamin C 176-700 Yes
- Peptides 320-950 Da
As increase the penetration of the cream in practice?
- By destroying the protective layer of the skin
If the healthy skin be removed before the procedure, lipid film or to make light exfoliation, active ingredients have high chances to overcome the stratum corneum and to go a little deeper.
- Due to hardware techniques
Now quite a lot of procedures that promise to deliver active ingredients and all sorts of vitamin cocktails in the deep layers of the skin (spoiler — not all promises can be trusted).
For example, iontophoresis and phonophoresis ultrasound – it is working. In these cases, the ingredients are “driven” deeper with the help of galvanic current of low power and low voltage and ultrasound.
Fractional lasers can burn the microchannels in the skin (microcolony) due to the fact that heat the water in the dermis. While they are still not healed, as they work through the “gate” through the epidermis, and these are the cosmetologists, for example, applied a serum with growth factors, vitamins and peptides.
There are even devices, which can be applied to the substances under pressure are often used for this purpose aqueous solutions of low molecular weight substances, who “wauwautosa” into the skin to provide a local effect (for example, JetPeel or HydraFacial). But how deeply they deliver the active ingredients is the big question.
- Enhancers penetration (no, it’s not a spell from Hogwarts)
There is a very large group of substances, which increase the permeability of the skin. Orasmaa Tiina Meder in one of its publications mentioned that there are already over 300!
For example (suddenly) is water. If the amount of water in the stratum corneum to increase the permeability of it will increase! This is a big plus for use of facilities with water-soluble ingredients. So are moist occlusive mask, impregnated with active substances and/or sensitive skin. After removing the mask the stratum corneum quickly dries and permeability returns to normal, what is valuable.
Some other popular enhancers work more selectively and with continued use can Horny layer damage:
- alcohols (such as glycols, polyglycols, glycerol) increase the amount of water in the skin and destroy the lipid layer, but can (and probably will) irritate;
- essential oils (contain ingredients which themselves penetrate deeply and “drag” the other active components). The deeper we penetrate, the more annoying. The “Glubokoye” essential oils — bergamot, juniper and some citrus. This is one reason why the complexes with essential oils is very important to strictly monitor their quality. For example, terpineol is an active ingredient of oil of juniper, often used as an ingredient in cream, a few minutes after the application is found in fat cells, that is, at the level of the hypodermis.
- fatty acids break down fats of the stratum corneum and pushed deeper into that with them mixed, but can be drying, so how to destroy the lipid film with constant use (namely, it holds water in the skin).
Occlusion is sAmelina evaporation. Water continuously rises from the depths of the skin to the surface and then evaporates. Therefore, if you slow down evaporation by covering the skin with something gas-tight, the water content in the epidermis will increase quite quickly. If the polyethylene film, the Horny layer swells, and the protective barrier destroyed.
If the regular cream on prepared (e.g., cleaned and ambilingual) skin, and the top to use the occlusion, some of its ingredients can penetrate into the deeper layers of the epidermis and even into dermis.
Occlusion is different, most often we encounter it, making wraps, during paraffin or closing the mask film.
In theory, this method is beautiful and comfortable, but as always there are nuances.
Liposomes, nanosomes, lipid nanoparticles and microgui help active ingredients of the cream to get deep into the skin, allow uncertain and difficult components to change the structure and “get along” with each other, their gradual emancipation, and, therefore, the prolonged action of the drug.
“Nanomaterial — insoluble or biologicaly and specially produced material with at least one external size or internal structure is in the range from 1 to 100 nm” (Technical regulations of the CU 009/2011)
In practice, there is still no definite answer on how can affect nanoelements on us in the future, because they can get into the bloodstream, in addition, there are a number of technical difficulties in which nanoelements are sometimes combined to form larger conglomerates and then, of course, the skin nothing will penetrate.
Tightness of the skin — beauty myth. Drag any of the active substances deep into it – not such a difficult task, and the cost of funds does not say anything about where it gets into reality – indeed, essential oil can be much cheaper funds in the peptides.
But how realistic is this necessary? Most cosmetic products work perfectly on the surface of the skin, because the main task is to solve the problem, but not at any price to push hialuronico deeper. Undue desire to do so, on the contrary, can lead to negative and unintended consequences: irritation, allergies, inflammation, disruption of the protective functions or even systemic reactions. In General, no wonder means from the official “deep” penetration certified as medicines, and their safety and efficacy are investigated much more serious.
Thank Tiina Meder Orasmaa for assistance in the preparation of the article and advice!