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5 Tests to Investigate your IBS

By Danielle Elliott
from Tummy Rescue

Irritable Bowel Syndrome (IBS) is said to affect 1 in 5 Australians at some point in their life. For some it can be months of dealing with bloating, pain, gas, diarrhoea, constipation or a mix of both. Others suffer with symptoms for years or even a lifetime.

IBS is a diagnosis of exclusion, generally my patients are told by their GP or Gastroenterologist they have IBS after other conditions have been excluded with basic medical tests. Some of my patients have been told they have IBS, with no tests conducted. IBS is called a functional disorder, as there is said to be no physiological change to the gut or pathology detected.

In the field of  Natural Medicine we are very good at supporting deficiencies in the functioning of the gut, but we also look for causes of your IBS. I want to discuss with you 5 tests, that can help you investigate your IBS.

Coeliac Serology

One of the first things I check when patients present with an IBS diagnosis or IBS symptoms in my clinic is if they have had Coeliac Serology through their GP. Very important to know too, is I ask were they eating gluten at the time the test was completed. Having a Coeliac Serology test while on a gluten free or low gluten diet, is not conclusive and could yield false negatives.


Calprotectin is a stool test, that looks to measure an inflammatory protein produced in the GI tract. Elevated levels can point towards inflammatory bowel disease, as opposed to IBS. This would need to be further investigated.

SIBO Lactulose Breath Test

As SIBO (Small Intestinal bacterial Overgrowth)  can be an underlying cause of around 50%-84% of IBS patients symptoms, the SIBO breath is very indicated. SIBO is an overgrowth of bacteria in the small intestine and can produce extreme bloating, pain, reflux, excess gas and depending on the gases formed constipation, diarrhoea or a combination of both. Patients with SIBO can also experience more systemic symptoms like brain fog, fatigue, joint pain & mineral deficiencies.

The breath test should measure methane and hydrogen levels every 20 minutes for a 3 hour period. The gas levels and the increases observed over the 3 hours period, should be used to guide the type of treatment that will be most effective.

Organic Acid Test

The Organic Acid Test (OAT) is a urine test that measures chemical compounds we excrete as a part of the normal (metabolism) function of our bodies. These compounds can tell us a lot about what is going on inside the body. As a practitioner I use it to get very accurate information on intestinal yeast and bacteria overgrowths. It also gives us lots of other information on neurotransmitter (brain hormones), vitamin and oxalate levels. These can all have an impact on your digestive symptoms.

Microbiome testing

There are many tests that will look at the make up of the microbial community that lives in your lower gut. After much research we know what bacteria species and roughly the numbers that make up the microbiomes of healthy individuals as compared to those that have a medical condition.

Microbiome testing can help us to see if there are changes we can make including antimicrobial herbs, probiotics, prebiotics or dietary to shift your microbiota in a more favourable direction. There are many test available on the market today, but you do want to be discerning. My 2 favourites are Microba and GI Effects, as I feel comfortable with the technology and science they use.

*Please note that more serious diseases should not be overlooked. These symptoms can be due to a functional problem or just as easily to a specific disease like Coeliac Disease, Inflammatory Bowel Disease or Diverticulitis. Therefore investigation & ruling out more serious conditions is definitely advisable.

Interested and want to find out more? Book in for Danielle’s webinar, where she will discuss IBS, it’s possible causes and the testing you can use to investigate what is going on for you.

More about the author

Danielle Elliott_4
Danielle Elliott
– Tummy Rescue

Danielle Elliott, Adv Dip (Nat & WHM)

Danielle Elliott is a naturopath, herbalist, and homeopath with a special interest in digestive complaints. She has been in clinical practice for 15 years and began specialising in gut health 9 years ago. Since then, Danielle has published a book entitled "Gluten Free and Happy", which helps educate people with Coeliac Disease and Non-Coeliac Gluten Sensitivity on how to optimise their digestive health and overall wellbeing. Danielle also does a lot of work with patients with SIBO and functional digestive disorders in her clinic “Tummy Rescue” (see and also works with Dr. Nirala Jacobi and the team at the Biome Clinic, consulting with patients world-wide. She is also proud to be an ambassador for the ATMS Natural Medicine Week 2022.

Danielle is hosting a webinar for Natural Medicine Week on the "Top 5 tests to investigate your IBS", book your tickets now!