How Cosmetic Use Changes the Microbiome

Almost everyone in developed countries uses cosmetics, from body washes to make-up. In the US, the cosmetics industry makes over $56 billion dollars in revenue. As a society, we use a lot of personal care products. And in order for those products to have a useful shelf-life, they contain antimicrobials – no one wants to open their hair gel and find a fuzzy patch in there.

But just like how antibiotics have had a huge impact on human microbiota, especially in terms of resistance, I wondered how antimicrobial use in cosmetics affect our skin microbiota. It has an effect, no doubt, but is it significant and can we say anything about positive or negative effects on human health? Should it be as huge a concern as antibiotic use? And how prevalent is antimicrobial use in everyday products or even food?

The most recent antimicrobial to get attention from the public was Triclosan, which is used in a variety of everyday products, including personal care items. Triclosan has been correlated with allergies and has raised worries of antibiotic resistance. However, there are other antimicrobials in products we regularly use on our skin. For instance, titanium dioxide is widely used in food and personal care items primarily as an anti-fungal. There are a few studies researching the effect of using products containing titanium dioxide, but even fewer of these examine the effect on the skin microbiome. In fact, a lot of skin microbiome research can be summarized as follows:

The human skin microbiota can be affected by many environmental factors, such as temperature, humidity, pH, exposure to air and light, and host factors, such as genetic background, body locations, gender, immune response, hygiene habit, use of antibiotics and antimicrobial detergent, and cosmetic use.

Unsurprisingly, fungi (like yeast), have started developing resistance to common anti-fungals used in cosmetics.

It shouldn’t be surprising by now that antimicrobial resistance is so prolific in our human environment. It is always surprising to become aware of where these antimicrobial compounds exist.