Influence of UV filters on the texture profile and efficacy of a cosmetic formulation

Objective Considering that many cosmetic products contain UV filters in their composition and that few studies have evaluated the role of UV filters in the physical properties and clinical efficacy of these products, the aim of this study was to assess the influence of UV filters on the properties and immediate effects of a cosmetic formulation. Methods Four cosmetic formulations, vehicle (V), vehicle containing UV filters (F), vehicle containing cassava polysaccharides and alfalfa (A) oligosaccharides and vehicle containing UV filters plus cassava polysaccharides and alfalfa oligosaccharides (multifunctional formulation, M) were developed. The texture profile of the formulations was analysed with a TA.XT plus Texturometer®. Twenty female volunteers aged 39–45 years were then selected for the assessment of immediate clinical efficacy of the formulations under study and of transepidermal water loss (TEWL), stratum corneum water content and microrelief of the skin obtained with their use. Results The presence of UV filters resulted in an improvement of the physical properties of the multifunctional cosmetic formulation (M) and of skin microrelief. However, the presence of UV filters also caused a significant decrease in hydration. Conclusion The presence of sunscreens had a negative influence on immediate skin hydration and TEWL. On the other hand, it positively influenced parameters related to the physical properties of the multifunctional formulation and skin microrelief. Thus, we conclude that the influence of UV filters on the development of cosmetic formulations is an important factor to be considered because it can have either positive or negative effect on the efficacy of the product. Résumé Objectif Étant donné que de nombreux produits cosmétiques contiennent des filtres UV dans leur composition et que peu d’études ont évalué le rôle de ces filtres dans les propriétés physiques et dans l'efficacité clinique de ces produits, l'objectif de cette étude était d’évaluer l'influence des filtres UV sur les propriétés et les effets immédiats d'une formulation cosmétique. Méthodes quatre formulations cosmétiques, un véhicule (V), un véhicule contenant des filtres UV (F), un véhicule contenant des polysaccharides de manioc et des oligosaccharides de luzerne (A) et un véhicule contenant des filtres UV ainsi que des polysaccharides de manioc et des oligosaccharides de luzerne (formulation multifonctionnelle, M) ont été développés. Les paramètres de texture des f