Connecting the Dots: From Skin Barrier Dysfunction to Allergic Sensitization, and the Role of Moisturizers in Repairing the Skin Barrier

The various functional levels (microbiome, chemical, physical, immune) of the skin barrier are all necessary to maintain skin integrity and are highly interdependent. Dysfunction can occur at solitary or multiple points and may have a domino effect on other levels. It is increasingly clear that barrier dysfunction leads to allergic sensitization, the atopic march, and CD. Thus, maintenance and restoration of the skin barrier are paramount to preventing these conditions. This may be achieved to greater and lesser degrees through the use of various moisturizers. 

In an ideal product, each aspect of the skin barrier would be considered. Attributes such as avoiding preservatives that can damage the microbiota while perhaps even having pre- or probiotics to support the microbiota, using pH-neutral and gentle ingredients to support the chemical layer, combining occlusives, humectants, and emollients for the physical barrier, and avoiding fragrance and common allergens and irritants to minimize the chance for immune activation are all desirable and should be considered when evaluating a potential moisturizer. 

S. Seité is employee of La Roche-Posay, France. M. Lin has served as a consultant for L’Oreal/La Roche-Posay. P. Lio has served as a consultant and speaker for L'Oreal/La Roche-Posay. He has also been a consultant/advisor for Micreos, Pierre-Fabre, Johnson & Johnson, Syncere Skin Systems, Altus Labs, AOBiome, Galderma, IntraDerm, Unilever, and is a board member of the National Eczema Association. T. Lazic Strugar has served as a consultant for L’Oreal/La Roche-Posay. P. Lio and T. Lazic Strugar received a writing grant from L'Oreal for this manuscript. A. Kuo has no conflicts. 

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