Balancing the skin microbiome: fact or fiction


Skin Clinical Research Consultants, NY, USA


The “skin microbiome” consists of the skin’s resident microorganisms (bacteria, archaea, fungi, viruses) as well as their genomic content and metabolic by-products. Modern techniques for sequencing DNA have enabled researchers to find microbes that could not be cultured in the lab using traditional microbiology culture techniques. Skin microflora is influenced by environmental conditions, temperature, humidity, clothing, exposure to pollution as well as internal factors like diet and psychological stress, thus making it very challenging to study and understand. Nevertheless, the cosmetic industry is teeming with products claiming to “balance” the skin microbiome. There is no doubt that there is a serious shift in microbiome diversity of diseased skin versus healthy skin. However, healthy skin is balanced already, so claims to balance healthy skin with cosmetics is somewhat a fallacy.
Studies are needed to determine the variations in the day to day, week to week as well as seasonal and other environmental factors on healthy skin microbiome of untreated skin to determine if the changes observed from cosmetic products is meaningful.

Human skin is a complex barrier organ that prevents moisture loss, helps regulate body temperature and protects the body from pathogens. The skin microbiome is comprised of trillions of bacteria, fungi, viruses, archaea, and small arthropods which colonize the skin surface; it is comparable to a living throbbing ecosystem flourishing on the skin, all around the body. This ecosystem is in a symbiotic relationship with the host via complex signals of the innate and the adaptive immune systems.


In order to maintain a healthy tissue homeostasis, interaction of the skin microbiome with the immune system is vital for optimal barrier function, pathogen defense, and tissue repair via production of key anti-inflammatory and anti-microbial compounds (1). This symbiosis of skin and its microbiome leads to a well‐controlled but delicate equilibrium. However, the skin is constantly exposed and affected by exogenous factors such as temperature, humidity, clothing, exposure to pollution as well as endogenous factors such as diet and psychological stress. Physiological and behavioral changes, related to age and the amount of contact ...