Choosing the Right Functional Test

specialised gut health testing how to choose the right gut test gut health naturopath herbalist digestive health SIBO IBS IBD

With each and every patient I work with I recommend specific individualised gut testing. Today I wanted to outline my process and why it is important to consult with each patient before choosing and ordering tests.

Individualised Medicine 

Each and every person that comes to the Byron Herbalist clinic is an individual. Many root cause drivers may overlap but the health journey that each patient has been on is unique.  

Occasionally, probably due to the wait time to see me, patients ask for testing to be recommended before their first consultation. I understand the thinking. If you have been unwell for quite some time wouldn’t it be better to get the testing out of the way and have results ready for your first appointment? 

The problem with this approach is ordering the appropriate test. There is an array of testing that I frequently recommend depending on history, presenting symptoms and clinical assessment. 

Recommended Functional Testing

To truly understand why it is impossible to recommend testing before seeing you I wanted to list some of the tests I frequently recommend. Each of these tests cost between $200-$500 dollars.  

  • Blood testing for specific nutrient deficiencies, liver markers, anaemia, lipid studies, thyroid health 
  • Large bowel stool testing – here there are two or three tests I regularly choose from each week depending on the patient.
  • Small bowel breath testing – even though SIBO is becoming more recognised as a root cause of many digestive symptoms I am still amazed at how often the small bowel has been overlooked
  • Leaky gut testing – assessing intestinal permeability which can be a big driver of food intolerances, skin health and autoimmune conditions. 
  • Organic acids testing (OAT) – this urine test is a helpful 10,000 foot view of the biochemistry of the body. It can assess mould, fungi, bacteria, nutrients, metabolism and more. 
  • Mycotoxin urine testing – mould affected patients often have a long history of feeling unwell. They also tend to be very treatment resistant. If a patient is not progressing as well as we had hoped, mould will be on my radar. 
  • Genetic testing – For very stuck patients gene testing can help to illuminate why they are not progressing well. I rarely use these tests but have found them helpful in certain patients. 
  • Heavy metal hair testing – There are caveats with hair testing and interpretation can be challenging. With that said, hair testing can show exposure to heavy metals.

If we ran each of these tests on every patient the lab bill (that you would have to pay!) would come to approximately 1500-2500 dollars. Not only is that far too expensive, it isn’t necessary. Ordering more than two or three labs at one time is overkill for the vast majority of the patients I work with. 

Now how do we choose the right labs? 

The Initial Consult

In our first appointment our job together is to form an understanding and develop a working theory, more of a hypothesis than anything.

From here choosing the right testing comes down to 3 important overlapping things. 

  1. Your presenting symptoms 
  2. The initial insult on your health, what I call your ‘never been well since’ moment 
  3. How long you have been unwell and your health journey

After an initial consultation I can filter through all the information and determine the appropriate testing.

Often I am fairly confident that a certain test – say a SIBO breath test for example – will be positive. So why test at all? Why not save the money on testing and just treat?

I have considered this approach and even spent some time recommending less testing.

Currently I am firmly in the ‘test don’t guess’ camp. Getting an objective insight into a patient’s health is invaluable. It is well worth an initial investment of $300-600! 

Test Review and interpretation Consult

When the test results have arrived the next step is interpretation. There is an art and a science to proper test interpretation.

I have seen significant results be completely ignored on functional tests that patients have ordered with past practitioners. One particular patient had one of the worst cases of methane SIBO that I had ever seen and her gastroenterologist had completely dismissed the results because the hydrogen production was low. 

Working on methane reduction strategies has improved her health considerably! While she isn’t back to 100% digestive health yet, understanding her root cause – excessive methane production in the digestive tract – we are now on the right track and can use targeted treatments. 

Another important point supporting the need for targeted testing is that I am not always right. 

Small intestinal bacterial overgrowth, or SIBO, is a perfect digestive condition to illustrate this point. There are many other conditions that mimic the symptoms of SIBO (article coming soon) including exocrine pancreatic insufficiency and fungal overgrowths like Candida

While most natural treatments will help to resolve these conditions, knowing whether it is SIBO, candida or an enzyme insufficiency will help to get patients better faster.

Ongoing support and follow up testing

Once we get some momentum and start to see symptom improvements I tend to see patients less frequently, stretching out our appointments further and further as symptom improvements become the new normal. 

If a patient is feeling 95-100% better then I don’t generally recommend follow up testing. 

If we have seen some improvements but not a complete resolution I will commonly recommend a follow up test to track any changes in the original lab values. This has been a hard lesson to learn. 

In early days of practice I would assume that the root cause had not been resolved IF a patient’s symptoms had not improved. While most patients do see their presenting symptoms improve when lab test results improve this is not always the case. A classic example of this is methane SIBO. Often patients are bloated and constipated. Most times when you clear the methane producing bug patients see an improvement in their bloating and bowel movements but not always. Sometimes treatment will effectively clear the methane bug but not the hydrogen producing bacteria that are always hiding under the methane bug – remember you need hydrogen production in the gut to make methane! There is always excessive hydrogen production when there is methane gas being made. 

In some cases clearing the methane SIBO picture can result in a worsening of bloating as the methane molecule isn’t there to mop up the excessive hydrogen production. Without retesting there would be no way to tell where we are at in the treatment timeline. 

Byron Herbalist – A unique treatment approach

My treatment model has evolved based on clinical experience, research and tracking patient’s progress. Currently, and I am sure it will continue to evolve and improve, it includes three foundational pieces. 

  1. Symptoms and history 
  2. Specialised testing, specific to the patient
  3. A targeted treatment plan generally including herbal medicine, prebiotics and probiotics.   

There is no ‘general protocol’ or testing that is broad enough to be recommended for every patient.

Each person has unique needs and needs to be treated as an individual.  

Now over to you. Has functional lab testing helped? Leave a comment below.

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  1. Wish it were possible to consult. But understand your licensing may not permit you to work with international clients. It has been a long haul, and I know that pieces of my picture are missing without the right testing. Thanks.

  2. I live in the US. Do you have any recommendations for a like-minded herbalist/practitioner? Thank you.

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