Background and objective: Despite numerous body moisturizers being available, cosmetic xerosis continues to be a leading skin problem for consumers. We performed two 35-day studies to evaluate the ability of a variety of body moisturizers containing various levels of oils/lipids, humectants, as well as other ingredients (e.g., niacinamide) to improve stratum corneum integrity.
Methods: 63 and 58 female subjects were enrolled and randomized in an incomplete block design to six of nine products (eight moisturizers or no treatment control) in studies 1 and 2, respectively. The primary endpoints included visual dryness by a qualified skin grader, skin hydration as measured by Corneometer, and barrier integrity as measured by transepidermal water loss (TEWL). The primary comparisons for the two niacinamide/glycerin moisturizers were to the other six moisturizers and to the no treatment control for each endpoint.
Results: The two niacinamide/glycerin moisturizers demonstrated an overall better solution towards rapid and prolonged improvement of cosmetic xerosis due to functional improvement of stratum corneum barrier function compared to no treatment and the other moisturizers tested.
Conclusions: These studies establish the benefit of including niacinamide in a body moisturizer to improve the integrity of the stratum corneum and thus reduce cosmetic xerosis over time.