Our fundamental research studies, conducted over the past ten years and the subject of patents and publications in internationally-respected journals, have demonstrated that your baby's skin is immature from birth until the age of 2 years: it has not yet acquired the resistance and qualities of adult skin. The skin barrier is therefore less effective, and more vulnerable and sensitive to external stresses (such as cold, wind, sun, rubbing, etc.). (The surface area to weight ratio in babies is 3 times higher than that of an adult, therefore requiring the use of different ingredients at different concentrations).Furthermore, depending on their skin type, your baby will have specific needs that Mustela can meet through its various product ranges. Each of these products undergoes a specific safety and efficacy assessment to ensure they meet the strict requirements needed for babies' skin. All of our formulas are associated with a toxicological evaluation based on the characteristics of babies’ and children's skin, as well as allergen and tolerance testing of the finished product. Our products meet the safety guarantees needed for the most fragile skins.