Illustration: Matija Medved

Optimize Me

No Showers, No Soap, Perfect Skin? Meet the Bacteria Facial

The skin microbiome is having a moment

Published in
5 min readJan 14, 2020


Optimize Me is an Elemental column exploring (and fact-checking) the weirdest self-improvement trends. It comes out every Tuesday.

DoDo you really need to shower every day or at all? And could showering actually be bad for your skin? Scientists and skin care companies are becoming increasingly aware of the billions of bacteria that live in and on our skin and the potential roles they play there, including eating our natural oils and sweat. Modern hygiene habits may be wiping out these good bugs, leaving us greasier, flakier, and at a greater risk of skin infections than if we just left our skin alone. Consequently, a movement is growing around the idea that people should scale back on the harsh soaps and hot water that have become the norm and let the bacteria just do their thing.

One company in particular, Mother Dirt — the cosmetic arm of AOBiome — is leading the charge. It’s developed a line of products that it claims are friendly to the skin’s microbiome and will let the bugs live in peace. Going one step further, Mother Dirt sells a spray containing a live strain of bacteria to repopulate one of the microbes they say we’ve washed away. The strain — Nitrosomonas eutropha, an ammonia-oxidizing bacterium (AOB) — eats the ammonia in sweat and produces nitric oxide, a molecule that’s important for blood vessel health and combating inflammation. Nitric oxide can also act as a natural antimicrobial, keeping bad bugs like Staphylococcus aureus (the cause of staph infections) at bay.

Nitrosomonas eutropha lives in the dirt, and according to Jennifer Cookson, director of research and product development at Mother Dirt, it existed on the skin of indigenous tribes and on people from “many generations ago before we started our westernized routine of washing every day as well as not interacting with our environment as much as we used to.”

Cookson says that adding back these bacteria and their nitric-oxide-producing abilities helps to normalize the skin, improving both oily and dry skin and potentially helping to treat acne and eczema. The company is currently running clinical trials to test the spray’s efficacy. However…



Dana G Smith

Health and science writer • PhD in 🧠 • Words in Scientific American, STAT, The Atlantic, The Guardian • Award-winning Covid-19 coverage for Elemental