Skin is the largest organ in the human body and plays a key role in defending against harmful external agents and in regulating body's water loss. The latest article by Miriam Deola - Cosmetic R&D Specialist and Nicola Lionetti - Cosmetic R&D Manager on Cosmetics&Toiletries, entitled Care and Repair for Compromised Skin, focuses on the skin's barrier function and the importance of lipids - such as cholesterol, fatty acids and ceramides - in its proper functioning.
Skin performs an important barrier function to protect the body from harmful external agents and to regulate its hydratation. Lipids in the skin contribute to the proper functioning of this barrier. There are basically three epidermal lipids:
In particular, ceramides play an essential role in maintaining the balance of the skin barrier. In fact, it can be observed that in some conditions, where the barrier function is compromised, there is a decrease in ceramide levels. Treatments with ceramide-based formulations can effectively help restore the balance of the skin, aiding its healing and reducing trans-epidermal water loss (TEWL).
For skin treatments, it's preferred to use water-in-oil emulsions, which tend to be more emollient, protective and water-resistant. However, oil-in-water emulsions can also be viable if characterized by nourishing texture and high substantivity.
Having defined the most appropriate vehicle, lipid emollients with strong reparative properties are, for example, squalane - derived from the hydrogenation of squalene and with great epidermal penetration power - and shea butter - endowed with powerful anti-inflammatory properties.
Recent research has shown that skin repair treatments using lipids similar to those present physiologically can contribute to the correction and healing of skin problems such as atopic dermatitis, psoriasis, acne vulgaris and photodermatosis. However, it is important that the molar ratio of lipids used be 3:1:1, with ceramides representing the majority (3).
Finally, you should keep in mind that when developing skin care formulations, it's important to limit the number of ingredients used to only those that are safe and strictly necessary. Careful selection of ingredients helps to preserve the integrity of the skin and maximize the effectiveness of formulated treatments.
From the selection of active ingredients to that of preservatives, the formulation of cosmetic products for topical use is one of the great challenges LabAnalysis faces daily in its laboratories.