Published Sep 9  |  10 min read  |  Get the FREE Leaky Gut Recovery Guide

How do you really test for leaky gut?  Well, whilst there are a number of tests out there, no single test will give you a definite yes or no.  Let me explain…

It took me a long time to even consider leaky gut as the culprit for many of my health woes.

After all, who’s walking around on a normal day wondering, “Hmmm, maybe my intestines are hyperpermeable”!

But when I first suspected I had leaky gut I did what everyone else would do…

…look for an objective test.

The main reason I wanted to know for sure is that leaky gut is a pretty serious condition and it takes a lot of hard work to fix it.

In other words, I didn’t want to spend months treating a condition I didn’t have.

When I started researching tests available and speaking to colleagues, I came across a variety of approaches to take.

P.S. if you show signs of leaky gut, check out my 7-page leaky gut recovery guide here.

The 2 ‘true’ leaky gut tests

You might read about all kinds of other tests, eg hydrogen breath tests, stool tests etc, but they are not specifically for leaky gut, ie for measuring intestinal permeability.

Instead they are for conditions that are associated with leaky gut. I talk about those tests below.

So the 2 ‘true’ tests to consider are…

  1. The old school lactulose & mannitol test. Even though most people were telling me they no longer rely on this test, it is perhaps the most direct test for leaky gut. Because all it looks at is how permeable your gut is. The way it does this is simple. You consume 2 types of non-metabolized sugar, one with large molecules (lactulose) and one with small molecules (mannitol), and then your urine is analyzed to see which sugars passed through your system. If the lactulose (larger molecules) find their way into your urine, your gut may be considered overly permeable, ie leaky.
  2. Blood zonulin test. This is the only real blood test for leaky gut syndrome and here’s how it works. So the main thing to know is that zonulin effects the gatekeepers of your gut lining (the things that decide what gets through into your bloodstream and what stays out), a.k.a. Tight junctions. Meaning it can change the size of the openings in your gut lining. So more of it, means openings increase in size and the lining becomes more permeable / leaky. Obviously we want some zonulin to ensure nutrients get through (and that’s why we have it). But too much and you can say hello to leaky gut! So this test is designed to see whether you have too much zonulin in your system and thus may have leaky gut. A more interesting question though is what causes zonulin levels to rise in the first place? Because if we can answer that, we can fix the problem itself. Generally, gluten plays a big role, as does candida / yeast, harmful bacteria and parasites. But in certain people, eg celiacs, zonulin can be found at high levels even without one of these four things!

1 related test worth considering

Let’s be honest. This is the test no one really wants to take. Whilst collecting some blood or urine is a walk in the park, this one is next level.

We are of course talking about stool tests. And not 1, but 2.

The idea here is that you collect 2 samples of your fecal matter over the space of a day, ie more than 12 hours apart. This will then be analyzed to determine bacteria levels (good and bad), presence of yeast (overgrowth) and parasites, immune function, digestive enzyme production, intestinal health in general and signs of inflammation.

So it is an interesting all-round test of the state of your gut health. You might end up finding out about conditions related to leaky gut too.

But the problem is that it offers an incomplete picture. Many bacteria and pathogens for example will simply not show up in your stool, since they stick to your gut lining. Whilst others will only show up occasionally, meaning your 2 samples could easily be missing the culprit.

Said differently, you would need to collect and analyze your poop very frequently in order to get a more conclusive picture. Not very realistic, especially when you consider one off stool testing can cause $400+!

How I ended up really testing myself for leaky gut

Instead of paying for expensive and inconclusive tests like the 3 above, I decided to do a 2-pronged holistic test on myself.

First, I compared my personal health history against all the signs of leaky gut.

After seeing I had several of the signs (food sensitivities, stomach pains, heartburn, brain fog, unexplained fatigue, IBS, and asthma / an autoimmune disease), and previously suffered from other signs of leaky gut (like eczema), I decided that there was ‘more probability of leaky gut than not’.

Given I had not been able to find any other reasoned diagnosis for my collection of symptoms, I was more than happy to finally have a working hypothesis.

Next I decided to embark on a 90 day leaky gut ‘elimination diet’, paired with smart gut-supporting supplements like L-Glutamine, Digestive Enzymes and Probiotics (they are links to 3 articles on this site that explain how these 3 supplements can help).

I figured that if after 90 days the 7 signs I had of leaky gut were gone or severely diminished it was because my gut had healed (and was originally leaky).

Within the first month of this protocol I already experienced a decrease or elimination of the majority of symptoms.

Stomach pains gone. Heartburn non-existent. Asthma 80% reduced. It was amazing!

And after the full 3 months I was in rude health. For example, I no longer carried antacids with me, rarely reached for my inhaler, woke up in the morning full of energy, worked all day with intense focus (and without coffee!), and I even noticed how much easier it was to gain lean muscle (probably because my body was able to absorb all the nutrition finally).

Whilst I could not be 100% certain I had leaky gut, I can be certain that the leaky gut recovery protocol, which you can find in my free guide here, worked to fix my health problems. And for me that is all the proof I need.

Of course n=1. In other words, this is but my own experience. Your results will differ, since everyone’s body is different.

But the great thing is that you have the power. First, check your personal health history against the 10 symptoms below. Then, consider a 90 day leaky gut protocol like me and see how you feel at the end. You should consult your doctor before undertaking such a protocol.

10 symptoms / signs of leaky gut – plus the tests you can take to prove them

  1. Food allergies / intolerances. As we know food sensitivities may arise when undigested food particles or toxins in general cross the (leaky) gut barrier and into your bloodstream. So what we’re saying is that to develop a food intolerance, overly permeable gut lining is a prerequisite. Basically here’s what happens: when food particles that shouldn’t make it through to your bloodstream, do make it, the body views these as intruders and works hard to raise the immune response and destroy them. Unfortunately, it might continue doing this every time you eat certain foods, especially gluten and dairy (it is scared!). And that’s the thing – foods you may have previously tolerated, can all of the sudden become intolerable, as the body is now fighting against them every time they show up. Although you can do the elimination diet, like me, to see what foods cause you grief, there are certain foods that might only cause you subtle pain. That’s where a food intolerance test comes into it. Without this test you won’t notice what those foods are and you might keep eating them, and thus experiencing ongoing, low level systemic inflammation. Ie your leaky gut will never completely heal. The main test to consider is the IgG food allergy test (other two are IgA and IgM). Since you’re suspecting leaky gut may be part of your problem it is often worth getting a candida test as part of this allergy test. All of this testing can be done from home with a simple dry blood collection. These tests will then look to see if your body is producing high levels of antibodies in your blood. Overall, this is an indirect blood test for leaky gut syndrome, so consider speaking to your doctor to see if it is worth taking (and paying for).
  2. Autoimmune conditions. For certain AI conditions like Celiac Disease, there is a very strong link with leaky gut. Whilst for other conditions like rheumatoid arthritis, Type 1 diabetes and asthma, the link is still strong, however it is not entirely clear which one causes the other. As a lifelong asthmatic I decided to simply test things out for myself. I figured if I undertook a leaky gut recovery protocol and then my asthma symptoms reduced, then there was a high probability that leaky gut was a contributor to my asthma and not the other way around. In my case, this turned out to be true. As my asthma decreased first to 80% and then to asymptomatic levels. Everyone is different of course. That is why it is wise to consult with your doctor and see what sort of personal program you can create together.
  3. Small Intestinal Bacterial Overgrowth (SIBO). Bacteria is good. In fact gut flora accounts for up to 80% of our immunity! But too much of the bad stuff tips you out of balance and an unbalanced gut flora can lead to leaky gut itself. So a condition like SIBO is a good (leading) indicator that you might be suffering from leaky gut.       Thankfully, unlike leaky gut there is a simple breath test for bacteria overgrowth. It’s not simply, ‘does this person have bad breath / halitosis?’. Instead, it’s the same test used to check for IBD and other GI disorders. All you need to do is consume a sugar-based solution (lactulose again!) and then breathe into a test tube or balloon-style device. You can even do this at home and send the results in. Basically what they’ll then look for is the level of certain gases like methane and hydrogen in your sample, which are produced by certain bacteria. Too high and you could have serious bacteria overgrowth. If you take this test make sure you avoid probiotics for 1 week prior (check with your doctor) and avoid alcohol, veg and fruit for 48 hours before the test. Avoiding these ensures bacteria measurements are accurate.
  4. Inflammatory Bowel Disease, eg Crohn’s Disease, Ulcerative Colitis or Diverticulitis. The link here with leaky gut is quite clear. The generally accepted connection is that intestinal hyperpermeability starts, then it leads to the development of IBD. Said differently, if you have IBD, you have leaky gut. There is no chicken and the egg problem here. Unsurprisingly then, there is also a strong connection between people who suffer with IBS and leaky gut.
  5. Digestive problems. I’m not just talking about diarrhea, constipation and heartburn/reflux/GERD here. But also more innocent things like excessive gas, bloating and burping. As someone who carried Zantac around with them full time from the age of 15 (!) I was able to tick a few of these boxes. Thankfully since I started eating clean and supplementing smart I haven’t experienced any of these digestion problems. Not needing to worry about running out of Zantac after a big dinner out is fantastic!
  6. Skin problems like eczema, acne, Rosacea, Hives, Psoriasis, rashes etc. There is a long history of leaky gut leading to skin conditions. In other words, the connection is not new. Probably most interesting is the speed at which these signs can disappear when you start following a proper leaky gut recovery protocol like this one.
  7. Brain fog or general fatigue or chronic headaches. This is something that can indicate leaky gut, but only if you’re experiencing it despite sleeping and eating well. Ie don’t use this to judge your chances of leaky gut if your overall health is in poor shape.
  8. Mood swings and depression. Given 80% of your serotonin is housed in your gut, it is no wonder we call the gut the second brain. So it is plausible to think that a leaky gut, which causes inflammation and havoc in general down there, could play a large role in how you feel. In fact, some studies have shown that up to 35% of depressed patients could have leaky gut.
  9. Allergies, eg seasonal, pet etc. Having sensitivities to cute little puppies is not a life I want to live! Thankfully the connection with leaky gut is similar to food allergies, which means it can be fixed through sealing up the gut barrier and reinoculating your gut with probiotics.
  10. Nutrient deficiencies. This one might perplex you somewhat. So as we know leaky gut is a problem because it sees bigger particles pass through your gut lining that shouldn’t. But here’s the thing…leaky gut can also mess with your gut lining, or more specifically, your gut’s microvilli, in such a way that whilst they let the big baddies through (eg gluten), they stop letting the small good guys through (eg nutrients). This can lead to nutrient malabsorption and vitamin & mineral deficiencies. Worse yet, since the good guys aren’t getting through, there is no one there to detoxify all the antigens being produced by your enraged immune system! It’s a double whammy. Thankfully there is a simple test you can do to see if you are nutrient deficient, and thus possibly suffering from leaky gut. It’s called an organic acid test. You simply order a kit to your home, leave a urine sample and then post it back. But here’s the thing…the lab does not test your urine for nutrient levels themselves, but rather for the acid levels. You see, high levels of acids – a byproduct of nutritional deficiency – will indicate much more accurately that your body is suffering malabsorption.

There are a few other signs of leaky gut to consider, eg autism, obesity etc, but for me the link is not quite there yet. I won’t be shocked if and when the link is established though.

What you should do today

Instead of spending $100s, if not $1000s, on tests that will not necessarily give you a clear yes or no, you might want to consider simply starting on a leaky gut recovery protocol today (here’s mine) if you have one or more of the 10 signs of leaky gut.

And then when the protocol finishes try a provocation diet to see what foods you can and cannot tolerate (like I did).

Of course you should make this decision in consultation with your doctor.

Here is a PDF of the leaky gut recovery protocol I used to say goodbye to leaky gut. It includes instructions on what to do every step of the way. It is nice and simple too.

Happy reading!

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