Sebum plays a role in skin barrier function and it is well known that its excretion rate is positively correlated to acne severity. However, it was previously shown by Yamamoto et al that acne patients have a diminished water barrier function. The authors suggested this impaired barrier function was caused by a qualitative modification of skin surface lipids, also known as dysseborrhea. The objective of this study was to assess the efficacy of a cosmetic product on sebum excretion reduction and skin barrier function improvement after repeated applications for 4 weeks, under the normal conditions of use, on adult females.
Twenty-four caucasian females with oily skin and presenting skin imperfections of acne type were enrolled in the study. They applied the tested product, Sébium Sensitive, on the entire face and neck twice a day for 4 weeks. Transepidermal Water Loss (TEWL) measurements were performed at baseline (D0), D7 and D28 on the cheekbone, using a TewameterTM TM 300 (Courage + Khazaka electronic). The skin surface lipid rate measurements were performed at baseline (D0), D7 and D28 on the forehead, using a SebumeterTM SM815 PC (Courage + Khazaka electronic), without skin degreasing. Statistical analysis was performed and significativity threshold was set at 5%. 
We observed a statistically significant decrease in the Skin Surface Lipid rate, after 1 and 4 weeks of repeated applications of the product (-16% and -32% respectively), in comparison with the initial values, showing an improvement of hyperseborrheic condition. We observed a significant decrease in the TEWL after 1 and 4 weeks of repeated applications of the product (-11% and -20% respectively), in comparison with the initial values, showing a favourable effect on skin barrier function.
Although the use of the product for 4 weeks resulted in a decrease in Skin Surface Lipid Rate, it also reduced TEWL of volunteers with acne-prone skin. It suggests that the BGM complex inside the product, by restoring qualitative sebum composition (as previously shown), helped the skin recover its barrier function.

Cosmetic product designed for acne-prone skin reduced sebum excretion and improved skin barrier function