Are probiotics helpful or harmful for Small Intestine Bacterial Overgrowth? (I asked an expert)

To use probiotics… or not to use probiotics – that is the question (when you have Small Intestine Bacterial Overgrowth).

And it’s a BIG question. In fact, it’s one of the most common questions we receive at ALL of our SIBO SOS™ Masterclasses.

While different practitioners have different opinions, I decided it was time for me to ask one of the most experienced researchers in the field of probiotics – Dr. Jason Hawrelak.

Dr. Hawrelak is the mastermind behind Probiotic Advisor and has over 15 years of experience as a researcher, clinician, and teacher.

I sat down with him for a Masterclass and Q&A to talk probiotics and Small Intestine Bacterial Overgrowth (SIBO). (Watch a preview of the Masterclass in the video below.)

Why Are Probiotics Controversial for SIBO?

The first thing I wanted to know: why does this controversy exist in the first place?

Dr. Hawrelak told me that it all goes back to a big misconception about HOW probiotics actually work.

As we know, SIBO is the result of an overgrowth of bacteria in the small intestine.

Normally, there should be very little bacteria in the small intestine – bacterial growth should occur in the large intestine. But with SIBO, bacteria migrates into the small intestine and starts growing there.

The overgrowth of bacteria is the basis for why some practitioners recommend against probiotics for SIBO.

The thinking is: why would you add MORE bacteria with a probiotic when you already have too much?

At first, that made sense to me – but then Dr. Hawrelak explained that this is based off a big misunderstanding about how probiotics actually work.

How Probiotics REALLY Work

Most people (including many practitioners!) think of probiotics as “colonizers.” That means: you take a probiotic pill, and the new gut bugs take up permanent residence in your gut.

So if you’re low in Bifido strains, you can just take a Bifido supplement and those new Bifido bugs will move in to your gut for good.

But this actually isn’t how it works.

Probiotics aren’t “colonizers” – they’re more like “helpful visitors.”

See, most probiotics do not take up permanent residence in the gut. Instead, they pass through the digestive system.

But they’re not just tourists – while they’re visiting your gut, they can perform many helpful actions.

This means that taking a probiotic supplement doesn’t just add more bacteria to an already-existing overgrowth.

In fact, taking a probiotic can actually help reduce overgrowth (more on that in just a minute).

What Probiotics Can Do

This is a real slide from Dr. Hawrelak’s SIBO SOS™ Masterclass.

Now we know: probiotics are much more than colonizers. They’re actually more like helpful visitors.

So what do these helpful visitors do while they’re in town?

Research has shown that there are multiple possible mechanism of action by probiotics that can benefit SIBO patients.

Here are some examples:

  • Stimulate the Migrating Motor Complex (MMC). The MMC are electrical waves that pass through the body are ultimately responsible for moving food through the digestive system by peristalsis. MMC waves are what causes your stomach to grumble or growl when you’re hungry. In many people with SIBO, decreased motility (aka the MMC not doing its job!) is either an underlying cause or symptom of SIBO.
  • Heal leaky gut. Leaky gut (aka increased intestinal permeability) is a coexisting condition of SIBO. It occurs when the tight junctions of the gut become “leaky” and allow undigested proteins into the bloodstream. This results in systemic inflammation that can cause a variety of symptoms.
  • Have Selective Antibacterial Properties. This means that some probiotics can specifically kill some bacteria living in the gut. They are like “special forces” seeking out bacteria that shouldn’t be there and killing it. This can help rebalance the gut ecosystem and reduce overgrowths.
  • Reduce visceral hypersensitivity. Visceral hypersensitivity is a side effect of SIBO  – it’s inflammation in the colon that causes nerves in the gut to be hypersensitive to stimuli. It can cause lasting pain and discomfort – but certain probiotics can reduce it.
  • Decrease intestinal inflammation. Inflammation in the intestines is at the root of many SIBO symptoms including pain and food intolerances. Long term, chronic inflammation can have devastating effects. Getting rid of inflammation in the gut is one of the surest ways to feel better.
  • Enhance secretory IgA. Secretory IgA is an antibody that is produced in the gut to help keep bacteria populations in check. Some people (either because of a genetic predisposition or a condition like SIBO) don’t make enough secretory IgA to control their gut bacteria populations – which can lead to SIBO (or cause it to be very difficult to resolve). Having more secretory IgA helps rebalance the gut ecosystem.

Probiotics Aren’t Just A Way to Add More Bacteria

As you can see, probiotics aren’t just a tool for adding MORE bacteria  – they have the ability to address root causes and symptoms of SIBO.

In a meta-analysis of research on using probiotics in SIBO, probiotics were significantly more effective at getting rid of SIBO than either placebo OR metronidazole (prescription antibiotic).

Probiotics also helped alleviate abdominal pain (one of the symptoms I have struggled with for years!).

This is a real slide from Dr. Hawrelak’s SIBO SOS™ Masterclass.

How To Make Probiotics Work For You

Probiotics absolutely have the potential to help you treat your SIBO symptoms – and maybe even get rid of it for good!

But not all probiotics work equally well – Dr. Hawrelak says there are some specific strains he doesn’t recommend for people with SIBO.

And other folks have additional sensitivities or conditions that must be considered when picking the right probiotic, too.

I wanted to know exactly how to choose the right probiotic for me, which is why I made the masterclass with Dr. Hawrelak.

Here’s what he covers in-depth at the Masterclass and Q&A:

  • The difference between species and strains of probiotics and why it matters
  • How probiotics are like dogs (yes, really!)
  • Probiotics and IBS – helpful or not?
  • How probiotics can stimulate the MMC
  • The truth about probiotics and brain fog
  • Probiotic myths you probably think are true
  • What is the microbiome and why it matters
  • What does the microbiome do for us?
  • Collateral damage of SIBO treatment
  • How SIBO diets can damage the microbiome (and what you can do about it)
  • How to read probiotic labels

  • What probiotic claims really mean
  • The importance of strain specificity when choosing a probiotic
  • How to dose probiotics properly
  • Why formulation doesn’t really matter
  • Novel uses for probiotics
  • Chance to ask your questions about probiotics
  • Not a one-size-fits-all probiotic recommendation
  • How to choose your own product based on what you’ve learned

More information on the Masterclass and recorded Q&A HERE.

I hope this article cleared up any misconceptions you had about probiotics and SIBO – and that you’ll watch the masterclass to learn how to pick the right probiotic for YOU.

There’s not one probiotic that works for everyone (Just Thrive is a great fit for me, but it might not be for you!) – that’s why I love this Masterclass – it teaches YOU how to pick the right probiotic for you.

So powerful!

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9 thoughts on “Are probiotics helpful or harmful for Small Intestine Bacterial Overgrowth? (I asked an expert)”

  1. LInda McCullough

    As someone who has studied/taught biology and microbiology, I understand these studies and think they have merit for me in dealing with chronic SIBO; however, I am reluctant to take more supplements regularly and wondered if it is feasible to achieve any significant effect from probiotics through foods (kefir, etc).

    1. Linda, did you watch the video clip in the blog post? In the clip Dr. Hawrelak explains the difference between probiotic supplements and fermented foods!

    2. Hawrelak says because they are wild strains we don’t know if they really have therapeutic effects or survive transit through the stomach.

    1. Angie – that is a question I have often wondered myself! I think it depends on what kind of SIBO you have, and where you are in the treatment. Dr. Hawrelak will be covering that at the Masterclass. Did you know you can watch the lesson as soon as you buy? Then if you have any questions he didn’t cover, you can pre-submit them – so if you don’t get all the info you need on prebiotics for your specific case, you can ask Dr. Hawrelak directly! Tickets are available here.

  2. Thanks so much for the continuing education! I will sign up for the probiotics class as I see there is so much more I need to learn.
    What can you find out about the ileocecal valve and its role in SIBO including possibilities for resolution? My physical therapist said all of her SIBO patients have a dysfunctional ICV. Thanks!

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