Tip: The Probiotic-Prebiotic You've Never Heard Of

Should you be eating dirt? Well, sorta. Here's what you need to know about SBOs or soil based organisms.

Probiotics are trendy, and for good reason. The bacteria in your gut are the true powerlifters of your body's overall health.

So you probably already know about the value of prebiotics, probiotic supplements, and eating fermented foods. But you're probably not eating dirt yet. Yes, dirt. More specifically, something called "soil-based organisms" or SBOs. Nope, this isn't hippy stuff. This is actually science-based stuff.

Soil-Based Organisms

No, you don't have to actually eat dirt. But you do need some of the stuff found in dirt for a healthy gut. SBOs are probiotics (live bacteria) and prebiotics (stuff that feeds the bacteria) that come from the soil. They've always been part of the human gut microbiome.

These spore-forming bacteria basically "seed" the digestive tract with good bacteria which flourish and support a healthy microbiome. Back before shiny grocery store produce, people gathered, grew and ate their own food. This produce was inevitably dirty, and people weren't as clean-obsessed as we are now.

In fact, something called "the hygiene hypothesis" is pinning the rise in many chronic conditions like asthma, allergies, and overall lowered immunity to the fact that our world has become overly sanitized. Because of this, we're not eating as much dirt as we historically have.

The Study

In a double-blind, placebo controlled study, one particular SBO was put to the test against IBS (irritable bowel syndrome). The study also wanted to identify the main symptoms experienced by those with IBS, which are:

  1. General illness and nausea
  2. Flatulence and indigestion
  3. Colitis. This is inflammation of the colon, which can show up as abdominal pain, diarrhea, and other super-fun symptoms.

Researchers took 25 farty IBS patients and split them into two groups. One group took 500 mg of an SBO twice per day. The other group got screwed with a placebo.

The Results

The group using the SBO had a significant reduction in all three of the main symptoms after a few weeks. Pretty impressive. Even though the sample size was small, the results were significant enough for the researchers to put their seal of approval on the stuff.

Let Them Eat Dirt

Some people worry about these organisms becoming pathogenic, but that has never been supported by the research. Keep in mind, it's possible for all strains to become pathogenic (even the good guys like lactobacillus) if things are out of whack. The key is balance.

Some initial side effects that could be seen as "negative" are a slight increase in bloating and digestive issues for a short amount of time. This is called a "Herxheimer reaction" and happens when you begin rebalancing your gut flora. Man up. It goes away quickly and you'll come out feeling better than before.

Make sure you're also eating small amounts of fermented foods each day (sauerkraut, kimchi, apple cider vinegar) to get other beneficial strains. You don't need to go crazy, but we do need SBOs as well as the other strains from fermented sources for a balanced microbiome.


  1. Bittner, Alvah et. al., "Prescript-assist probiotic-prebiotic treatment for irritable bowel syndrome: A methodologically oriented, 2-week, randomized, placebo-controlled, double-blind clinical study", Clinical Therapeutics 27, (2005): 755-761.
Tessa Gurley is the owner of Enliven Wellness, and a nerd about all things health and fitness. Tessa is currently working on her Master's in integrative medicine, and strives to empower her clients and readers so they can live their most vital lives. Follow Tessa Gurley on Facebook