How to recognize a damaged epidermal barrier?

What is skin made of?

The skin consists of 3 layers . Starting from the outermost one , we distinguish:

Epidermis ( Latin: epidermis )

The epidermis consists of:

• Keratinocytes – these are cells that produce keratin (a building block protein). They are formed in the basal layer of the epidermis. Over time, they lose their ability to divide, flatten, and flake off.
• Merkel cells – cells that receive sensory stimuli .
• Melanocytes – pigment cells that – as their name suggests – produce melanin (the pigment that determines the colour of our skin, hair and iris).
• Langerhans cells – they play an important role in supporting the immune system because they process information about microorganism antigens and, if necessary, stimulate the immune response.

Additionally, the previously mentioned keratinocytes are arranged in several layers , among which we can distinguish (also starting from the top):

• The stratum corneum ( Latin: stratum corneum ) is the outermost layer of the epidermis, composed of large, flat, anucleate cells filled with keratin. Some of the cells are arranged in a roofing pattern and form a compact part of the stratum corneum, while the rest are loosely arranged and are more easily exfoliated.
• Light ( Latin: stratum intermediale , also called luminous – lucidum ) – affects only places on the body where the skin is thicker (e.g. feet, hands).
• Granular ( Latin: stratum granulosum ) – intensive protein synthesis and production of glycolipids and sterols occur here, which create a layer impermeable to water.
• Spinous ( Latin : stratum spinosum ) – consists of 5 to 10 layers of polygonal, flattened cells. Together with the basal layer, they form the Malphigian layer – above this layer, the keratinization process begins.
• Basal ( Latin : stratum basale or germinativum ) – the deepest layer, where epidermal cells are formed. Melanocytes are also located in the basal layer.

Dermis ( Latin: cutis vera)

It is located just beneath the epidermis and is divided into two layers made of connective tissue: papillary (upper) and reticular (lower).

The dermis contains: blood vessels , nerve endings , and skin appendages (including sweat glands and hair follicles).

Subcutaneous tissue ( Latin: hypodermis )

It is made of connective and adipose tissue , which performs thermal insulation, protection and energy functions. The number of fat cells depends on a number of individual factors, such as gender , hormone levels and lifestyle .

What is a hydrolipid coat?

The hydrolipid film is a mixture of sebaceous gland secretions (sebum) and sweat glands (sweat). This film covers the stratum corneum of the epidermis and performs many important functions.

What are the functions of the hydrolipid coat?

• Regulates the pH on the skin surface.
• Limits transepidermal water loss .
• Reduces the negative effects of exposure to harmful external factors.
• Lubricates the skin.

The hydrolipid coat is removed each time you wash, but healthy skin rebuilds it in a relatively short time (from 1 to 1.5 hours). In addition to the hydrolipid coat, we must mention the stratum corneum of the epidermis , which resembles an unplastered wall.

The "bricks" are the cells of the aforementioned layer , and the "mortar" (binder) is the intercellular cement . This cement consists of a mixture of lipids and together with the cells of the stratum corneum of the epidermis creates (or at least should create) a wall protecting the deeper layers of the epidermis and the dermis from the undesirable effects of factors from the external environment.

A solid epidermal barrier (in combination with the hydrolipid coat) is one of the most important aspects of healthy and properly functioning skin.

To illustrate this effectively, I will tell you what would happen if the hydrolipid coat disappeared from the surface of your skin and the wall in the form of the epidermal barrier was not very solid .

The water in your body would evaporate like crazy – there would be no point in drinking 2 liters of water a day when all your H₂O resources would be floating around you in a moist mist during the heat.

Okay, maybe that's a bit of an exaggeration, but let's remember that our bodies have wisely and thoughtfully developed natural defense mechanisms against potential threats. It's worth keeping that in mind and taking care that the damaged epidermal barrier is just a medical curiosity!

What can disrupt the epidermal barrier?

Factors that may contribute to the disruption of the proper functioning of the epidermal barrier and hydrolipid mantle include:

• Improper care – for example, with cosmetics with an inappropriate pH for your skin or containing strong cleansing ingredients . Rubbing your face too hard with a towel can also cause you additional worries. A paper towel works best for drying your face, which should be gently applied to the skin after washing it. This is also a more hygienic option, because you can ruthlessly throw the used sheet into the bin.
• Excessive exfoliation of the epidermis - because if you exfoliate , do it wisely! The needs of the skin are different for each of us, but it is worth approaching the subject consciously and, best of all, with a dermatologist to determine the frequency and method of exfoliating dead skin. You can find more information on this subject here !

• Using too high a concentration of retinol – I know it’s tempting, but when it comes to retinoid therapy, patience and sensible dosing are key . It’s also good to keep in mind that it’s safest to include retinol in your skincare routine in the fall and winter (direct exposure to the sun can cause additional irritation and skin discoloration!).
• Genetic factors – this obviously refers to individual conditions and natural predisposition to certain skin ailments.

How do you know if the epidermal barrier is damaged?

A damaged epidermal barrier can manifest itself as follows:

• Hypersensitivity to cosmetics used . Do you know this? It seemed to you that your cosmetic routine was tailored PERFECTLY to your needs, but after a while it stings here, reddens there... Less is more , so it is worth treating the issue of used products sensibly and choosing them in such a way as not to overload the skin with unnecessary care steps.
• Itching, irritation , redness – and most often the whole package! If your skin feels dry and washing your face has gone from being a pleasure to a nuisance, it is probably the epidermal barrier and hydrolipid coat that are failing.
• Increased sebum production. You probably don't associate it with anything very positive (i.e. "shining"), but your skin needs sebum! It protects it from excessive water loss through the epidermis. Excessive sebum production is often a defensive reaction of the skin, which is activated when, among other things, it is dry or irritated.

If such symptoms occur, consult a dermatologist . In the next text, we will also give you some known methods of dealing with a damaged epidermal barrier. See you soon!

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