'Unhygienic make-up bags are rife with superbugs, scientists warn’ was the recent headline by the Cosmetics Business reporting on research by Aston University which found more than 90% of make-up products were carrying bacteria such as E.Coli and Staphylococci, which can cause blood poisoning and infections. The study has raised fears that people are unwittingly putting themselves at risk and its authors are urging manufacturers and regulatory bodies to do more to protect consumers.

The most well understood role of the skin is that it serves as a barrier between the human body and its external environment, preventing loss of moisture at the same time as preventing the entry of UV radiation, toxins, pathogens, allergens, and irritants.  However, the skin is also a biologically active ecosystem in which diverse communities of micro-organisms live. These microbial communities are known as the skin microbiome. We generally think of bacteria, fungi, and viruses as pathogens - foreign invaders seeing to harm us. In fact, pathogens are a minority among all of the microbes that populate our microbiome. Most of these microbes are not only harmless but are in fact beneficial, both in terms of our normal bodily functions a swell as protection from other pathogenic microbes.

Interesting fact: It is estimated that 100 trillion bacteria live in and on our bodies, with only 1% of the cells on our person are human, the other 99% are microbes. On our skin, there are 1,000 different bacterial species and up to 80 different fungi species. 

 

Skin microbes are usually non-pathogenic, and either commensals (are not harmful to their host) or mutualistic (offer a benefit). The benefits bacteria can offer include preventing pathogens from colonising the skin surface, either by competing for nutrients, secreting chemicals against them, or stimulating the skin’s immune system.

Alterations to the bacterial community structure or overgrowth of pathogenic microbes can cause problems including atopic dermatitis, acne, redness, irritation, accelerated skin aging, and more.

The skin microbiome prefers a relatively acidic environment (pH around 5.0), which also inhibits the growth of pathogens, thus protects us from infections. Whereas the opportunistic bacteria—the dysbiotic players—do better at a higher, more alkaline pH. Therefore alkaline topical products can contribute to increased risk of skin issues.