Scientists from L’Oréal Research and Innovation (France) and the Nestlé Research Center (Switzerland) report that two months of supplementation with the probiotic strain displayed significant increases in lactobacilli counts in stool samples, compared with the placebo group, which measures of skin sensitivity also increased for the female participants.
“The results of this study demonstrate that the probiotic ST11, taken by the oral route, has a beneficial effect on reactive skin, i.e. decrease in skin sensitivity, increase in the rate of barrier function recovery, and maintenance of moisturising factor concentrations (urea and sodium lactate) in the skin,” they wrote in the journal Beneficial Microbes .
“These findings support the idea to further develop a probiotic-based nutritional approach for the treatment and/or prevention of the symptoms related to reactive skin.”
The findings have potential implications for the growing number of people with sensitive skin in developed countries, with data indicating that as much as 50% of women and 30% of men suffer from sensitive skin. Symptoms include feelings of heat, burning, stinging or itching, while the skin is also very sensitive to heat, cold, and wind, and to specific chemicals, particularly those used in topical products.
While many topical products have been designed to ease sensitive skin, scientists from L’Oréal and Nestle proposed a different way of dealing with the issue: “To act […] deeply from inside the body via an innovative nutritional approach”.
Led by L’Oréal’s Dr Audrey Guéniche, the researchers recruited 64 Caucasian women with sensitive skin to participate in their study. The women were randomly assigned to receive either placebo or the L. paracasei supplement (daily dose of about 10 billion colony forming units – cfu) for two months.
“Lactobacillus paracasei NCC 2461 (ST11) was selected because of its specific beneficial skin properties discovered in in vitro studies, i.e. diminution of neurogenic inflammation and promotion of the recovery of skin barrier function,” they explained.
Results showed that, in response to capsaicin skin tests, the probiotic groups displayed a “clinically significant” reduction in skin sensitivity, compared to placebo. In addition, there was a trend towards less skin dryness of the leg, but that did not reach statistical significance.
“It is currently postulated that, subsequent to the interaction between probiotics and the intestinal epithelium, the associated immune cells are activated resulting in a release of immune mediators, such as cytokines, into the blood stream,” wrote the researchers. “This may contribute to reinforcing or restoring skin homeostasis.”
Source: Beneficial Microbes
June 2014, Volume 5, Number 2, Pages 137-145, doi: 10.3920/BM2013.0001
“Randomised double-blind placebo-controlled study of the effect of Lactobacillus paracasei NCC 2461 on skin reactivity”
Authors: A. Guéniche, D. Philippe, P. Bastien, G. Reuteler, S. Blum, I. Castiel-Higounenc, L. Breton, J. Benyacoub