Each of us has a unique skin microbiome, leading some of us to be more susceptible to acne than others for reasons we can’t quite explain (yet).
The main acne-causing bacteria – Propionibacterium acnes – has provided some clues as to the nature of acne development, but this bacteria also exists on healthy skin, and is not the full story when it comes to successfully treating acne.
The real cure, or at least better management techniques, may include the facilitation of different types of skin bacteria working in harmony to protect our skin from infections. Skin dysbiosis is characterised by a lack of diversity in bacteria, which may also occur in the intestine, and respiratory and reproductive tracts, as well as the skin.
Why the bacterial genome matters
Over 500 species of bacteria live on healthy skin, with over two million genes expressed amongst them. Humans only have 20,000 genes, making us genetically vastly more bacterial than we are human. This system of life means working together with our bacteria for survival – we need them just as much (or even more) than they need us. We are at one with our microbiome, creating a superorganism. Part of this symbiosis is creating harmony, so when one element is off, we are left out of balance: this is dysbiosis.
The nature of skin bacteria
Skin bacteria are many and varied, and each bacteria has the areas of our skin it prefers: moist, dry, oily, dark, light. For example the forearm will have different types of bacteria compared to our armpit or groin areas, or skin creases or folds, or our scalp.
A 2012 study in four healthy volunteers showed that the microbiota from four swabbed areas of their bodies varied immensely in diversity and composition of bacteria present. Factors that alter this diversity and composition of bacteria include our age, immune system, gender and genes, but also where we live, what we eat, what animals and other creatures we are around, and our daily activities. Environmental factors are meaningful, because we our skin is in direct contact with many elements each day.
How skin microbes affect skin conditions
Our skin microbes are now known to play a role in many skin conditions, such as eczema and psoriasis. A lack of diversity of bacteria has been found on the skin (including clear skin) of those with acne, and in successful acne treatments, healthy skin microflora is restored. Interestingly, while antibiotics are one way in which we deliberately destroy parts of our microbiome to cure disease, some research has indicated that acne patients receiving antibiotics had greater facial microbiota diversity after treatment than before.