401 The Human Stratum Corneum
compromising the SC barrier and the skin microbiome. Even if all the ingredients on
their own are mild in clinical testing, when formulated with other ingredients, the fully
formulated systems can be harsh, and therefore it is important that fully formulated
systems are tested for clinical mildness and skin benefits.
With the increasing consumer desire towards switching to more sustainable and greener
chemicals, the importance of understanding the functional role of newer chemicals and
their impact of the SC structure and function will become significant in the coming
years. Availability of biomarker assays, increased use of in vivo imaging and spectroscopic
techniques, wearable in-vivo methodologies, advanced data collection, and analysis using
AI driven technologies will help guide the technology development with newer and safer
ingredients.
Our improved understanding of the SC biological and biophysical properties over the past
three decades will now lead to novel approaches and ingredients that will provide enhanced
benefits in the coming years. Some of the areas that will receive increased attention in the
coming years include enhanced skincare for population segments such as skin of color,
very elderly skin, sensitive skin, and infant skin. The impact of cosmetic ingredients
and products on the skin microbiome also will become an active area of research in the
coming years. These will offer challenging and exciting opportunities for introducing new
ingredients and products that are safe and sustainable in cosmetics and personal care in the
coming decades.
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