Microbiome is the latest buzzword in skincare, but what on earth is it? Is it legal to utilize it in cosmetics? What are probiotics in cosmetics? Do you have many questions hovering in your mind? ZMUni is here to help.
I. What are probiotics?
The concept of probiotics is originally from food science. Presently, the most widely accepted definition is ‘living microorganisms that, when administrated in adequate amounts, confer a health benefit on the host’ by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO).
However, due to the difficulties such as keeping probiotic activity and level, probiotics normally are not added directly to cosmetics. Instead, substances derived from probiotics through the fermentation process or non-viable probiotic products are utilized in cosmetics. They have the potential to restore the skin microbiome so as to reinforce its immunity system.
It, therefore, needs to be weighed and measured carefully to make efficacy claims involving probiotics.
II. What is Microbiome Skincare?
At present, microbiome skincare is achieved mainly through the following two approaches.
Most recently, a prebiotic has been defined as ‘a substrate that is selectively utilized by host microorganisms conferring a health benefit.’ Prebiotics are mainly carbohydrates, such as fructooligosaccharides, lactose, sorbitol, xylitol, etc. They can preserve and reinforce skin health by moisturizing and promoting the production and reproduction of symbiotic bacteria.
Postbiotics are metabolites or fragments of cell walls produced by probiotics that do not contain living cells, for instance, substances derived from probiotic fermentation, substances derived from the fermentation of probiotic-agricultural products, substances derived from the fermentation of medical fungi and herbal products, etc. Postbiotics, a group of low-weight-molecular compounds with multi-activities, provide nutrition for the skin. Meanwhile, they can stimulate the gene expression of surrounding tissue cells and microflora. Therefore, they can preserve and reinforce skin barriers and the immunity system
Since cosmetics are one of the external factors influencing skin microbiome, great consideration is required in researching and developing products, for instance, cleaning ability, pH control, the use of preservatives, the use of prebiotics and byproducts from probiotics, etc. The products shall not only reach their functions as cosmetics, but also keep the balance of the skin microbiome.
According to research, phenoxyethanol and methylparaben have the least effect on indigenous bacteria at concentrations that can inhibit Staphylococcus aureus and Escherichia coli. Additionally, in the formula of microbiome skincare, 0.50%~1.00% 1,2-pentanediol did not show any inhibition on 5 kinds of skin bacteria within 24h. However, when the concentration increases to 2.00%, it has an obvious inhibitory effect on propionibacterium acnes after 6 hours. Therefore, the concentration of preservatives and their impacts on the skin microbiome should both be taken into consideration in developing products.
III. How to make efficacy claims of microbiome skincare products in compliance with laws and regulations in China?
The Standard for Efficacy Claims of Cosmetics lists 26 types of efficacy claims, but microbiome skincare is not one of them. The microbiome is a mechanism like anti-saccharification and anti-oxidation claimed in many products. It is often utilized to restore the balance of the microbiome to accelerate skin metabolism, repair skin barriers, etc. It, therefore, is associated with many efficacy claims, such as hair loss prevention, moisturizing, spot removing, whitening, repair, soothing, etc.
The ingredients such as substances from lactobacillus fermentation, filtrate from dichotomous yeast fermentation, extracts from lactobacillus/soybean fermentation, etc are used in many products. The association between their skincare mechanisms and efficacy claims is verified by many enterprises. However, the concept of microbiome skincare has not been widely known by consumers. Besides, there are no scientific definitions and verification of probiotics or prebiotics on the skin surface, which will cause a certain degree of misunderstanding. It is, therefore suggested that enterprises should make claims on the efficacy of ingredients added to their products instead of using ‘microbiome skincare’.