Part Two: The Importance of a Healthy Skin Barrier
The skin barrier is a dynamic system that plays an important role in maintaining skin health and overall well-being. It serves as a multifaceted defence mechanism, fulfilling several crucial functions to ensure the body's protection and harmony.
One of the primary functions of the skin barrier is to prevent excessive water loss from the body, known as transepidermal water loss (TEWL). The outermost layer of the epidermis, the stratum corneum, together with its lipid matrix, acts as a barrier against moisture evaporation. This helps to maintain optimal hydration levels within the skin, which contributes to its suppleness, elasticity, and overall health. Proper hydration is not only essential for the skin's appearance but also for its proper functioning and resilience (Denda et al., 2016).
As well as maintaining hydration, the skin barrier acts as a physical shield, protecting the body from a wide range of external threats. It forms an effective barrier against harmful microorganisms, such as bacteria and fungi, preventing them from getting deeper into the body. The stratum corneum's compact structure and the presence of antimicrobial peptides provide an innate defence against potential infections (Gallo et al., 2017).
The skin barrier also acts as a protective shield against environmental factors, including pollutants and UV radiation. Environmental pollutants can penetrate the skin and lead to oxidative stress and inflammation, which can accelerate skin ageing and contribute to various skin conditions. The skin barrier acts as the first line of defence, reducing the penetration of these pollutants and minimising their adverse effects. The stratum corneum provides a barrier against the harmful effects of UV radiation, shielding the underlying layers of the skin from damage caused by the sun's rays (Svobodova et al., 2015).
The skin barrier also acts as a guardian against irritants and allergens. It helps to minimise the penetration of potentially irritating substances, preventing them from triggering inflammatory responses or allergic reactions in the skin. The integrity of the skin barrier is crucial in maintaining a balanced immune response and reducing the risk of hypersensitivity reactions (Kim & Kezic, 2019).
A healthy, intact skin barrier is essential for optimal skin function and overall well-being. When the skin barrier is compromised or impaired, a variety of issues can arise, including dryness, sensitivity, inflammation, and increased susceptibility to infections.
Understanding the importance of the skin barrier encourages us to make mindful choices in our skincare routine. By selecting gentle, pH-balanced cleansers, moisturisers enriched with barrier-supporting ingredients, and protective products, we can enhance the integrity and function of the skin barrier. Avoiding products that contain harsh surfactants, preservatives and avoiding over-use of chemical exfoliants (including AHA and BHA) or aggressive synthetic actives such as retinol is also important. Practicing positive skincare habits such as avoiding excessive exfoliation, protecting the skin from extended sun exposure, and maintaining a balanced diet and lifestyle can contribute to a strong and resilient skin barrier (Chamlin et al., 2008; Im et al., 2018).
By prioritising the health and well-being of our skin barrier, we can enjoy not only a radiant and vibrant complexion but also the confidence that comes with knowing our skin is protected and nurtured.
Chamlin, S. L., Kao, J., Frieden, I. J., Sheu, M. Y., Fowler, A. J., Fluhr, J. W., ... & Williams, M. L. (2008). Ceramide-dominant barrier repair lipids alleviate childhood atopic dermatitis: Changes in barrier function provide a sensitive indicator of disease activity. Journal of the American Academy of Dermatology, 58(2), S7-S17.
Denda, M., Sato, J., Tsuchiya, T., & Elias, P. M. (2016). Stratum corneum acidification in neonatal skin: Secretory phospholipase A2 and the sodium/hydrogen antiporter-1 acidify the neonatal rat stratum corneum. Journal of Investigative Dermatology, 136(4), 745-754.
Gallo, R. L., Nakatsuji, T., & Huang, C. M. (2017). The skin microbiome. In Cold Spring Harbor perspectives in medicine (Vol. 9, No. 2), a018271. Cold Spring Harbor Laboratory Press.
Im, M., Lee, M. K., Park, G., & Kim, J. H. (2018). Effects of lifestyle and the environment on the skin microbiome. Clinics in Dermatology, 36(1), 15-22.
Kim, J. E., & Kezic, S. (2019). Causal relationship between epidermal permeability barrier dysfunction and immune abnormalities underlying atopic dermatitis. Experimental Dermatology, 28(5), 452-456.
Svobodova, A. R., Galandakova, A., Sianska, J., & Dolezal, D. (2015). DNA damage after acute exposure of mice skin to physiological doses of UVB and UVA light. Archives of Dermatological Research, 307(1), 53-62.