Is an organic acid test (OAT) worth it? An integrative doctor's review

A lot of articles out there are written either by functional medicine doctors who earn from the test, by the laboratories or clinics that sell it, or by conventional doctors who have not really spent much time looking into it. The honest truth is that I do not earn anything from testing - purely from my consultations and treatments, where nutrition and supplement advice can be incorporated.

I think what is honestly the most important going forward is patients becoming more informed on the tests available, their potential benefits and drawbacks, so they can make more informed decisions and ask better questions of the doctors treating them. That is the purpose of this article.

Because I think the only thing that truly matters in the end is the most optimal long term health outcome.

So, is an organic acid test worth it? Do I recommend it?

No, not as a first test. But the full answer is more interesting than a simple no.

The organic acid test is a big-picture test, a metabolic picture of your overall health, not a specific answer to one problem. And from my perspective, whilst I think treating any single marker on the report doesn’t make any sense, in the right hands, partly due to the complexity in its interpretation, I do believe this test has genuine potential.

One of the biggest drawbacks to me about this test is cost, and whether you can get just as good results without spending on the test. I think that will typically be the biggest bottleneck for many patients.

But I have to also be honest about my position. Because I typically treat using my background in conventional medicine, Ayurveda and Chinese medicine, I may also have certain subconscious biases of my own.

However, I am genuinely open to functional medicine testing. I do think it is an advancement on modern medicine in certain ways and if a new model is emerging, I think all of us as doctors should have an open mind when analysing tests and treatments that may be of benefit to patients.

Therefore whilst I do not typically advise this test currently, if I truly believed it would improve the results I achieved, I would definitely be open to changing my perspective on this.

What is an organic acid test?

An organic acid test is a test used in functional medicine to look for metabolic imbalances. Organic acids are metabolites, the products of your body’s metabolism.

Metabolism, put simply, is the process that breaks down food to give you energy. Inside every cell, pathways break down the fats and carbohydrates from your diet and run the reactions that keep you alive.¹

Your body flushes these organic acids out in your urine, so a morning urine sample can measure them. If a metabolic pathway is struggling, the metabolites it produces can build up or fall, and those changes can show up on the test.

Read carefully, they can give useful clues about how your body is processing nutrients and energy, and in some cases about what your gut bacteria and fungi are producing too.

What it is

• A urine test.
• It can add useful clues about how your body is processing nutrients and energy.
• It can generate hypotheses.

What it isn’t

• A diagnostic test (except for inherited metabolic disease, as used in conventional medicine).
• It rarely provides a single definitive answer by itself.
• A specific test for one problem, like a breath test for SIBO or a zonulin test for leaky gut. It gives you a diverse picture of the inner workings of the body.

How does an organic acid test work?

You collect the first urine of the morning, following the kit’s instructions, freeze it, and send it directly to the laboratory by courier.

The science behind it is metabolomics: the study of the metabolic reactions in your body, by measuring what those reactions leave behind, the metabolites. The laboratory uses chromatography to separate the metabolites by their structure, and mass spectrometry, which breaks the compounds apart using a process called ionisation, to measure how much of each there is.¹ A metabolic imbalance, or inflammation related to your gut, may then show up as abnormal organic acids on your test.

What does an organic acid test show?

I think the big thing an organic acid test can potentially do is help you build up a metabolic big picture for:

• detoxification and methylation, including glutathione^{2, 3}
• cellular metabolism, and how efficiently your mitochondria produce energy⁴
• neurotransmitter balance: dopamine, serotonin and noradrenaline^{5, 6}
• nutrient deficiencies, B vitamins in particular, which are important for metabolic efficiency^{7, 8}
• bacterial and fungal overgrowth in the gut microbiome, including oxalates⁹

A skilled clinician who knows the important markers and their interconnectedness with various other internal and external processes can then argue that it can be used to better guide treatment.

Is an organic acid test useful for gut health?

The metabolites in your urine come from your own cells and from your gut microbiome, which contributes a large share of them.¹⁰ So whilst a stool test can tell us which microbes are present in the gut, the field of metabolomics seems to be an attempt to tell us what those microbes are actually doing. The rationale for the urine test is that it can give you a bigger picture.

For the gut, there are a number of potential markers, such as arabinose, D-arabinitol, hippuric acid and p-cresol, which can create suspicion of conditions such as candida,¹¹ inflammatory bowel disease¹² and C. difficile,¹³ but typically a stool test would be needed to verify these results.¹⁴ A practitioner can argue, for example, that certain markers are indicative of yeast affecting the Krebs cycle and therefore interfering with cellular energy production.¹⁵ Another pattern may be indicative of how well you are absorbing certain amino acids, which could then have a rebound effect on your mood.^{16, 17} This thinking honestly makes some sense to me.

But the honest truth is that whilst on the surface a lot of this research seems quite promising, I think many of these are simply the breakdown products of amino acids,^{13, 16} and these markers are also affected as a result of various dietary factors such as the intake of red wine, berries, whole grain wheat and rye, coffee and dried fruit,^18–22 in addition to other factors such as age, toxin and environmental exposure.^23–25

So whilst I do think metabolomics is a promising, growing area of research, most of the microbial markers on popular urine organic acid tests do not seem to be reliable markers of gut dysbiosis or overgrowth. For assessing gut health in many cases, a stool test seems to be more useful for issues such as C. difficile, inflammation and parasites.^{14, 26, 27}

When is an organic acid test clearly useful?

In conventional medicine, we use this test to diagnose genetic disorders affecting roughly 1 in 2,000 births, due to the accumulation of metabolites in inborn errors of metabolism.^{1, 28}

When can an organic acid test be worth it?

To me, organic acid testing does really fit a gap we have in conventional medicine. A lot of chronically ill patients suffer from poor energy, and often have little in their bloods to explain it.²⁹

I think the world is currently undergoing an explosion in medical research surrounding cellular health, which at its core is related to energy production.

And considering my additional background in Chinese medicine and Ayurveda, in both of these practices, “qi” or “prana”, roughly translated as life force energy, are fundamental concepts (although with different frameworks of understanding) for optimising the healing process.

You then take into account the importance of minerals, vitamins and micronutrients, which I would argue are one of the core elements of a good nutrition plan.^30–32 They work together, not in isolation,³³ for the digestive process,³⁴ for the activation of enzymes^{34, 35} and for hormones to be built.^36–41 This is in the context of our current agricultural system, where I would say a lot of us genuinely have suboptimal levels of minerals and vitamins.^{42, 43}

Therefore, taking all of the above into account, when I read this from a biochemical perspective, and considering I also work with intravenous vitamin drips and supplements as part of my approach in a number of cases, I especially find this area of research very interesting.

Therefore, the rationale from a functional medicine perspective honestly makes a lot of sense to me when considering issues such as:

• ongoing fatigue
• complex symptom clusters
• to get a baseline of where you stand
• to guide nutrition and supplements
• a suspected nutrient-related bottleneck
• a person who has persistent symptoms that have not been addressed
• an individual who wants more insight into the patterns more than the diagnosis
• a clear plan for how these results will change the next steps

I think it is important to read that last point again. Because that may be the most important deciding factor.

When should you have other tests first?

I can’t think of any situation where foundational blood tests shouldn’t be ordered before an organic acid test, especially for patients whose symptoms strongly point to a specific condition with a clear diagnostic pathway, or who are looking for a quick yes-or-no answer.

Whilst it gives an overall big picture, from a functional medicine perspective there are other tests that may be better for issues such as nutrient deficiencies, intestinal permeability, food sensitivities and parasites.

Why can organic acid test results be misleading?

These metabolites could be high due to:

• diet^{23, 44, 45}
• supplements²³
• gut bacteria¹⁹
• collection timing^{24, 44}
• day-to-day variation⁴⁴
• issues with your digestion
• a number of other conditions²³
• or nothing at all.

That’s why I think a big concern from my perspective is treating single markers.

Three concerns with the organic acid test

There are three concerns I primarily have with this test.

Firstly, it was built for rare genetic disorders. Functional medicine is taking this test and applying it to the general population, and the research on its use there is still new, so the data can conflict. This is why what matters most is a clinician who understands this research and your full case in context, and can see how relevant these pathways realistically are: with a detailed understanding of the biochemistry, and also of the bigger picture, your mind, your body, your spirit and your energy. If they have a good baseline knowledge of your health, the organic acid markers then have the potential from my perspective to help them figure out what may be missing.

Ideally, they are not in a position where they profit from the test they order and the supplements they sell you, which from my perspective can create a conscious or subconscious bias.⁴⁶

Secondly, each laboratory reads it differently. Whilst there are published technical standards for the laboratory analysis of these organic acids,¹ each lab seems to have its own reference intervals, and its own way of preparing and extracting samples. This means you would have to keep using the same company, because you cannot compare one laboratory’s results with another’s. In all honesty, I have found the same issue with blood tests from different laboratories across the world, in the patients who come to see me. So I suspect this is a problem with conventional testing too.^{47, 48}

Thirdly, the artificial intelligence engines behind the report. These engines are commercial products, and they are increasingly being built to scale. I use AI to help streamline my own work, and I think it can be useful, but I find plenty of errors on a daily basis. At my scale, I can make sure, to the best of my ability, that these errors get rectified, and if anything goes wrong as a result, I can’t blame AI or an algorithm: the fault rests with me.

But what happens if one of those small errors is scaled to thousands of patients inside one of these algorithms, whether in the instrument itself or in the interpretation engine?

Imagine a small error creates abnormal numbers in the way the test is recorded, or in the way the engine reads it. The best case is that a patient gets a diet or supplement plan from the algorithm and benefits from it, even though those markers might not have been the strongest cause of their issues. The worst case is that they never needed any of it, they lose a lot of money and do not get better, or get worse.

Separately, I also see doctors using language models to help with diagnosis. That can be useful. It can also dull the critical thinking of the person treating you, and create a culture where they start to treat numbers instead of the human being in front of them.⁴⁹

From a business perspective, these companies may choose not to show their algorithms, to maintain their competitive edge. But with a lack of transparency and public scrutiny, who is most likely to suffer as an end result?

Who should read your organic acid test results?

In my view, conventional testing can often be quite straightforward to understand. To put it very simply - high white cells, an infection; low haemoglobin, anaemia; high CRP, inflammation.

But with organic acid testing, you really need to understand the biochemistry in depth and how it is connected to a large number of other factors, from your diet and your environmental exposure to what is going on in a patient’s psyche, their lifestyle, their circumstances, which current scientific literature may not have made connections with yet.

I think if more doctors started using organic acid testing, it could go one of two ways:

• The best case from my perspective is that it gets used to build a bigger picture. Doctors refresh and build on their knowledge of cellular biochemistry and read it in the context of a genuine full history and the likely factors in that patient.
• The worst case is that doctors start treating the numbers on the report and prescribe expensive treatments that are not needed, making the patient worse long term whilst they believe they got better because of short-term symptom improvements. And the patient either does not realise what has happened, or they can’t really do anything about it, because the doctor was simply following a defined protocol. All of it could have been prevented without the report.

Questions to ask before an organic acid test

Before ordering one, I would ask:

• What are the possible solutions you could offer based on the results of this test?
• Can those results be achieved in any other way?
• Could there be a cheaper solution that can at least be roughly similar in how effective it can be long term?
• What is the plan for follow-up and reassessment?

Do I use the organic acid test?

Do I typically recommend it? No.

But if money were not an issue, do I think this test has the potential to provide genuine value if interpreted well? Yes.

From my current perspective, we have healed people for thousands of years without any of these in-depth numbers, and I think we can heal people now without them. In my practice, when a person suffers from fatigue, gut issues, mental health problems and chronic health problems with tests that come back normal, I personally believe I have a strong way of getting good results without this test.

However, if or when I am confident this test can provide genuine additional improvements for patients who can afford it, and improve their quality of life in addition to or instead of what I currently do, I will definitely start recommending it.

What I do instead. My approach is one I have genuinely created using my background in conventional medicine, Chinese medicine and Ayurveda. My only goal is to create the strongest results. You can see my method here.

What would change my mind. Speaking to other functional medicine doctors, integrative medicine doctors, and even the laboratories themselves, which I plan to do, whilst continuing my own research and keeping a close eye on the literature.

In particular, three questions: does acting on these results improve patient outcomes? How reliably can certain results identify the problems they are proposed to identify? And how accurately do the laboratories measure these metabolites?

There is always more to know, and I simply do not know what I do not know. This is my honest current opinion, based on everything I have read so far.

How much does an organic acid test cost, and can you get one in the UK or Europe?

The laboratories that offer it around the world include:

• Diagnostic Solutions Laboratory
• Genova Diagnostics
• Great Plains Laboratory, now Mosaic Diagnostics

Genova and Great Plains are the two best-known providers. Genova’s direct prices only apply within the continental United States. Mosaic Diagnostics offers ordering outside the US through its international site, and states that tests for people in the EU are intended for lifestyle and wellness purposes.

The truth about cost is that it is rarely the test itself. It is what happens afterwards: the supplements prescribed, the repeat testing, the protocols. That is something you should take into account when making your decision, and it depends on the professional reading your result, not the laboratory.

These were the prices when this article was published. Prices move, so please check before you buy. This is provided so you can have a rough idea.