We tried Mother Dirt so you don't have to


After many years of operating under the assumption that bacteria are fundamentally and universally bad for our bodies, science is finally catching up to the reality that things just aren’t that simple. We now know that the relationship between our bodies and the microorganisms that inhabit them is much more nuanced. While there are certainly pathogenic “bad” bacteria that we all want to avoid, there’s an entire bouquet of beneficial and necessary “good” bacteria that live in harmony with us, making up what is now referred to as the human microbiome. The surface of our skin and its various nooks and crannies is home to droves of good and bad bacteria that do everything from cause acne to heal wounds and preserve moisture. As it turns out, when we cleanse our bodies with traditional soaps and body washes, we are doing daily to our skin what antibiotics do to our gut.

Enter AO Biome, a company looking to set things right in the world of skin bacteria. AO Biome is a recent startup that is making and selling a line of products by the irresistibly au naturale name of Mother Dirt. The idea behind the Mother Dirt line of products is that, among the many species of bacteria that the average American’s skin is missing, there is one important type that our ancestors all had and that we are distinctly lacking. That component is Nitrosomonas, a variety of bacteria naturally found in dirt that converts certain chemicals in our sweat into other chemicals that are important to the normal functioning of our cells. While these types of bacteria are utterly benign to humans, they are extremely susceptible to death by detergents and other chemicals commonly found in soaps. Thus, as the theory goes, while our ancestors evolved a you-scratch-my-back-I’ll-scratch-yours relationship with these microbes, modernity has exterminated them from the surface of our skin.

The Mother Dirt package entails, quite simply, a bottle of live Nitrosomonas that you spray on your skin, accompanied by shampoo and body wash that are specially designed not to harm these bacteria. The idea is that you replace all of your personal care products with the ones provided in the package—including nixing deodorant, moisturizer, dry shampoo, the works—and apply the live bacteria spray to your body instead. The little guys take care of everything—the stink, the acne, the dry skin, etc.

When I learned about Mother Dirt and the premise behind it, the scientist in me was intrigued; the startup junkie in me was tickled; the hippie in me was star-crossed. I’ve long fantasized about science cracking the key to the no-poo, minimalist bathing lifestyle, although nothing I’ve yet tried has worked. With a long list of failed personal hygiene experiments under my belt, I nonetheless held out hope for the Mother Dirt lineup and set off on a two-week trial of the stuff to heal my skin microbiome.

What follows is an account of my experience with Mother Dirt and how things changed when I replaced my entire hygiene routine with a little bottle of good bacteria.

Day 1:

On the first day of the experiment I savored my last full-fledged shower before saying goodbye to all of my normal cleansers. After emerging, I applied the spray to my body, especially my armpits and face. At the time I was deep in the throes of an acne outbreak, and since I had to go cold turkey on all of normal remedies the spray was my only hope.

My boyfriend caught me in the act of applying the stuff and asked what would become of my deodorant during this experiment.

“No deodorant,” I replied grimly.

He looked at me, horrified. “None at all?”


And so it begins.

God help me. God help my poor boyfriend.

Day 2:

On the second day I washed my scalp with the Mother Dirt shampoo, which was surprisingly effective at removing the oil from my hair.   I am normally a very oily person and expected that I would need to use some of my own shampoo at least periodically throughout the two weeks, so the effectiveness of the Mother Dirt shampoo was a pleasant surprise.

I cleaned my face and body with the body wash, spritzed myself thoroughly with the spray, and went about my day.

At the time I was getting around on crutches due to a sprained ankle. I found that I had greatly underestimated the effect of two rubber pads rammed into your armpits while you huff and puff around all day in the summer heat. Using crutches is hard work, and by mid-day I was able to detect a little bit of stink, but only if I went out of my way and smelled my pits. I reapplied the spray once, and then again later on in the day. By the end of the day there was no detectable body odor whatsoever.

My acne was somewhat better, although I attributed this to the breakout running its normal course rather than the effect of the spray. I reapplied to my face before bed, and this became my face care routine for the two weeks—spray once in the morning, and once in the evening.

Day 3:

The third day of my experiment will be remembered in infamy as “The Ripening.”

From the moment I woke up, I was aware of an odor coming from my pits. However, I was planning on doing some gardening this morning so I didn’t shower or apply the spray immediately in anticipation of the situation getting worse before it got better.

Indeed, my expectations came true, and over a short time outdoors I became extraordinarily smelly. I truly could not remember the last time I stank that badly, if ever. I am not typically a very smelly person. Normally my once-daily application of deodorant carries me through the whole day, including heavy exercise and Arizona summers. I found my previously unbeknownst capacity for stench horrifying, but thankfully the stink cleared up with a shower. The shampoo did a good job removing the sweat and oil from my hair again, and I realized that I probably wouldn’t have to use my normal shampoo as I had expected.

I spritzed and went about a very sedentary day of work. But despite my lack of exercise, by 3:00 PM the stink was back—and it was bad enough that I had to cheat. I shamefully applied a swipe of deodorant to each pit, and resolved to do better the next day.

Day 4:

I awoke with high hopes that Day 4 would not be a repeat of Day 3, but these hopes were quickly dashed. Despite my liberal application of the spray, by mid-day I was stinking powerfully.

And I wasn’t the only one suffering.

I lifted my arms to hug my boyfriend, and the look on his face told me that all was not well in the olfactory department.

“You’re…ah, you’re a bit ripe down there,” he confessed.

I apologized profusely and applied more spray, but it was no use. I couldn’t get the stink to disappear completely, no matter how much of the good bacteria I slathered onto me.

On the bright side, my acne was continuing to clear, and I hoped that the spray had something to do with it.

Day 6:

From the moment I awoke on Day 6, I was an odorous abomination. Now being aware of the effect my aroma was having on those around me, I found it necessary to put on deodorant from the very first of the day. I wasn’t happy about my faltering commitment to the experiment, but I cut myself some slack given that the average daily temperatures in Tempe, Arizona were above 110°F and humidity was hovering around 30 percent. Surely even an army of good bacteria can only do so much under conditions like that, right?

Thankfully, deodorant was the only sacrifice I had to make. All my other hygiene products remained tucked away, and the experiment slogged on.

Day 8:

On Day 8 I noticed that my hair was becoming limp and thin from the use of the Mother Dirt shampoo. The shampoo has been doing a great job of removing oil from my hair, but for some reason left it increasingly weak and listless. My hair is naturally curly, but with the use of the shampoo it couldn’t seem to hold a curl instead became awkwardly wavy. I wasn’t at all pleased about my volumeless hair and wondered if my scalp microbiome was actually healthier, because my hair certainly wasn’t.

Once again, I tried to get through the day relying merely on the spray but ended up having to apply deodorant. At this point I had to admit that I was fighting a losing battle with my own skin bacteria.

Day 11:

A few days before wrapping up the experiment, I officially gave up on trying using the spray as a deodorant substitute. With a heavy heart I forced to conclude that it was simply not humane to subject those around me to the odors of my unbridled microbiome. On this day, the armpit segment of Operation Mother Dirt was declared an uncontested failure.

My hair, too, was continuing to struggle under the Mother Dirt regimen. I resigned myself to having flat, lifeless locks for the duration of the experiment, and pressed on.

Day 14:

On Day 14 I woke up relieved. Today was the last day that I would have to feel guilty about using normal deodorant to control my stink. I was also really looking forward to re-establishing my normal hair texture, which I had taken wholly for granted until now. If nothing else, I emerged of this experiment with a deep appreciation for the capabilities of my normal cleaning products.

So maybe Mother Dirt isn’t all it’s cracked up to be, but I haven’t lost faith in my microbiome. I may have not found the philosopher’s stone healthy alternative personal hygiene products, but I wouldn’t call the experiment a total failure. The spray did seem to make a noticeable difference in my facial acne, as my breakup from the beginning of the two weeks cleared up expediently and stayed away. In fact, I plan to continue using the spray on my face for as long as it seems to work.

As for the rest of my cleaning products—tomorrow they’ll be making a much anticipated comeback from their early retirement.

Christine is a passionate social science scholar who works at a sustainable biotech venture capital fund.  She spends most of her spare time tending to her dogs, cats, chickens, and vegetable garden.