The Human Microbiome

You might have already heard of the “human microbiome”. It is the term used to describe all the genetic material of all the microorganisms living on and inside the human body. Microorganisms (otherwise known as microbes) are microscopic organisms, specifically bacteria, viruses and fungi. Most of these microbes are harmless or even beneficial. The importance of the microbiome has become a topic of interest in the last few years.

It is estimated that the human body contains up to three times as many microoganisms as human cells. Individuals have a total of 30 to 50 trillion bacteria and up to 100 trillion microbes in general. And while estimates vary, there may be over 1000 different species of microorganisms. Adding to the complexity is that each of us has our own distinctive combination of these organisms. These bacteria live on the surface of the skin and inside the mouth, nose and urogenital tract. Not surprisingly, most live in the large intestine.

The Skin Microbiome

The skin is colonized by a diverse collection of microorganisms — including bacteria, fungi and viruses — as well as mites. These microbes vary between individuals and also between skin areas within the same individual (think underarm vs face). The microbiome protects the skin against harmful bacteria or other microbes and has to constantly recover from daily stressors such as sunlight, pollution and chemicals in cosmetic products.

Probiotics, Prebiotics, Postbiotics and Skincare

Probiotics include various strains of helpful bacteria that occur naturally on skin and that can be applied via probiotic skincare products. Prebiotics are carbohydrates that serve as a food source for probiotic bacteria so they can function optimally. Postbiotics refer to the metabolic byproducts of probiotic bacteria that are responsible for many of the beneficial effects of probiotics.

How Probiotics and a Healthy Microbiome Help the Skin

The skin’s microbiome acts as a protective barrier to prevent bad bacteria and fungi from causing infections. This happens via bacterial competition, immune system regulation, enhancing skin barrier, and simulating the production of the body’s own antimicrobial peptides. Keeping the skin’s microbiome balanced also increases hydration by reducing TEWL, restores pH and regulates sebum production. These microorganisms influence the production of carbohydrates, vitamins, amino acids and lipids. A balanced microbiome improves skin complexion and decreases redness, sensitivity, acne, eczema and signs of aging.