SIBO and Digestive Enzymes: How the Pancreas Impacts Recovery

When it comes to SIBO and digestive enzymes, most of the focus tends to stay on the bacteria in the small intestine. But there is another piece that often gets missed. The pancreas and your digestive enzymes. Over the years, working with a lot of tricky SIBO cases, I started noticing a pattern. A lot of patients showed low pancreatic elastase 1 levels on stool testing, even when there was no major disease involved.

Elastase 1 is one of my favourite markers because it gives a good read on how well your pancreas is making digestive enzymes. The best part is, it is not thrown off by enzyme supplements, so it gives us a really clear view of what is actually going on. Low levels are usually a flag for something called exocrine pancreatic insufficiency, or EPI. This can show up with symptoms like bloating, gas, diarrhoea, and gut discomfort. Sound familiar?

Here is where it gets interesting. Almost every time I see low elastase 1 in clinic, the patient also has SIBO. When we support their enzyme production alongside treating the bacterial overgrowth, they tend to improve much faster.

In this article, I want to break down the connection between SIBO and low digestive enzymes, why it is not just a coincidence, and what you can do about it if you are stuck in the bloating and food reaction cycle.

If SIBO is new to you then be sure to check out our Complete Guide To SIBO here.

Understanding Elastase 1 and Pancreatic Function

Elastase 1 is quite an accurate, low cost and non-invasive test showing how active your pancreas is on the digestive enzyme front. It isn’t thrown off by external enzyme supplementation too which is handy (1). 

A gastroenterologist would use this lab along with other diagnostic criteria to rule in or rule out a condition called exocrine pancreatic insufficiency or EPI. Anything below 200 micrograms of elastase 1 per gram of stool should be looked at carefully by a prescribing doctor (2).

Testing for Low Digestive Enzyme Production

So the first step here is to determine whether you have SIBO or not.

Surprisingly testing for SIBO is more contentious than you might think. Below are my thoughts on SIBO testing after years of treating this condition.

Once you know you are SIBO positive or not the next step is to determine your root cause and treat both the bacterial overgrowth causing your symptoms (bloating, gas, distention, abdominal pain, food reactions, etc) and address the reason why – ie the root cause.

Any functional stool test worth the cost of the lab will be testing for elastase-1.

The labs that I’ve reviewed in my clinical practice that do test for enzyme production from the pancreas include

1. Complete Microbiome Mapping – Nutripath
2. GI-MAP – Diagnostic Solutions
3. GI-360 – Drs Data
4. GI-Effects – Genova Diagnostics

Now you might be thinking that involvement of the pancreas and low enzyme production is uncommon and if you follow the literature you’ll see that the most common causes for EPI are very serious conditions like chronic pancreatitis (the most common), pancreatic tumours, cystic fibrosis and conditions like coeliac disease and inflammatory bowel disease (4).

Let me tell you here, I see lab low elastase 1 frequently (remember I can’t diagnose any conditions) so I’ll refer patients here back to their prescribing doctor to get worked up and rule out any of the significant diseases and underlying conditions of EPI. 

Why Low Pancreatic Enzymes Matter in SIBO

So far, and I’m not saying it doesn’t happen, not one of the patients that we’ve clocked this issue with has had a serious condition with their pancreas. And almost every one of these patients, bar two, have had SIBO! 

Now that doesn’t mean that there isn’t an overlap with the common drivers of EPI and SIBO. In fact a systematic review looking at the frequency of SIBO in chronic pancreatitis saw that over ⅓ of patients with chronic pancreatitis had SIBO (5).

That’s a whopping number! 

As always we’re trying to find and treat the root cause we’ll need to determine whether SIBO causes the low enzyme output from the pancreas or does low enzyme production cause SIBO? Which way does it go?  

Can Low Digestive Enzymes Cause SIBO

We have good evidence showing that poor enzyme production from the pancreas can cause small intestinal bacterial overgrowth and the biggest piece to support this is that proteolytic enzymes and the pancreatic fluid are both antibacterial (6, 7).

We have one study (true on dogs) showing that EPI led to small intestinal bacterial overgrowth and that when they were supplemented with pancreatic enzymes it reversed the SIBO (8). This is a huge insight into how impactful poor enzyme production from the pancreas can be on the microbiome balance in the small bowel.

Can SIBO Cause Low Digestive Enzyme Production

On the other side of things there is the case to be made that SIBO can lead to EPI and the resulting symptoms and this poor enzyme production could then lead to a persistence of the bacterial overgrowth in small bowel. A bit of a vicious loop!

We know that the majority of EPI cases are from conditions that lead to damage to the actual pancreas organ but remember I see frequently EPI in the clinic and have never seen this common root cause of organ damage before. I still refer back each and every patient with lab low elastase 1 to their prescribing doctor to be thoroughly evaluated 

Something else must be going on. 

We see EPI as a result of some coeliac and inflammatory bowel disease cases due to ‘a loss of intestinal brush border proteins’ (9) which would equate to damage to the gut lining and intestinal hyper-permeability. 

Now we’re not quite there in the literature but I am comfortable saying that in most of my patients with SIBO and EPI there is evidence of gut damage and even leaky gut either as

Here we can see a link between that damage and a lack of response from the pancreas leading to poor release of digestive enzymes, leading to less control of bacterial growth in the small bowel, leading to more gut damage and around we go! Remember SIBO isn’t the only microbe that can lead to leaky gut. Candida is a common overgrowth that I see in the clinic every week and can be tricky to treat in some long standing cases.

Now what to do about it? 

Approaches to SIBO Treatment With Digestive Enzymes

I would typically approach these two issues we’ve outlines above, SIBO and low enzyme production from the pancreas or EPI if you have that diagnosis head on and simultaneously

#1. Supplement with pancreatic enzymes  

Using strong animal based digestive enzymes like these ones

#2. Treat the bacterial overgrowth head on at the same time

Herbs, probiotics and prebiotics are the mainstay for SIBO treatment in the Byron Herbalist clinic. Prokinetic herbal medicines play a huge role in recovering from SIBO too.

#3. Heal and seal the leaky gut! 

Generally I’ll hang off and recommend gut healing support after we have worked through treating SIBO.

Work With Me

Struggling with digestive issues like bloating, abdominal pain, constipation, diarrhoea, or histamine reactions? I work with patients one-on-one to uncover the root causes of chronic gut issues — whether that’s SIBO, Candida, dysbiosis, or inflammation.
Consults are held via video call and available across Australia and New Zealand.
Ready to get started? Book your initial consultation here.

References and Resources

1. Fecal Elastase-1 as a Test for Pancreatic Function: a Review
2. Faecal elastase 1: a novel, highly sensitive, and specific tubeless pancreatic function test
3. Introduction and practical approach to exocrine pancreatic insufficiency for the practicing clinician
4. Causes of Exocrine Pancreatic Insufficiency Other Than Chronic Pancreatitis
5. Systematic review and meta-analysis: Small intestinal bacterial overgrowth in chronic pancreatitis
6. Small intestinal bacterial overgrowth syndrome
7. Antibacterial Activity of the Pancreatic Fluid
8. The fecal microbiome of dogs with exocrine pancreatic insufficiency
9. Less common etiologies of exocrine pancreatic insufficiency