Organic Acids Test (OAT): Yeast and Bacterial Overgrowth

How metabolic testing takes the guesswork candida treatment

Organic Acids Test (OAT): Yeast and Bacterial Overgrowth

From a naturopath’s point of view, the digestive tract is considered the cause of many health issues and not just those related to digestion: aching muscles, fluid retention, weight gain, slowed metabolism, joint pains, concentration, headaches and skin problems as well as depression can have their source in the gut.

One of the principles of naturopathic medicine is to address the underlying cause of a problem in order to get the best result long term. You can’t do that if you don’t know what the cause is. This article will explain how we were able to accurately identify and successfully treat a common G.I. infection caused by a yeast called Candida albicans.

The gut’s connection to other health issues

I recently saw Helen, a patient who had been suffering from chronic fatigue for six years. She had gone through all the medical tests: hormonal, blood, etc. but no cause had been identified.

Although, Helen was naturally a positive person she was suffering from depression and postpartum. Her body often ached especially her muscles, making exercise nearly impossible and as a result she had become overweight.

It was clear that something was affecting Helen’s overall health – and it seemed Helen’s digestion was the root causes as there was bloating and discomfort too.

I also wondered about allergies and whether there were any infections in her intestines causing her symptoms.

After such a long struggle, Helen was keen to find the underlying cause. We did a blood test to look for food intolerances and a urine test called the Organic Acids Test (OAT) t. The OAT test looks for yeast and fungal toxins as well as many other waste products of metabolism, giving a wider view of the internal functions.

When the results arrived, Helen had no food intolerances or allergies at all, which was unexpected. However, her urine test revealed the underlying issues: she was overwhelmed with toxins produced by yeast in her intestines. See her result here.

The usual Candida yeast sufferer has two or so of these toxins elevated. In Helen’s case: seven yeast toxins, several at extreme levels were causing her fatigue and mood disorders.

Helen’s report was the worst I’ve seen and considering she was appeared to be coping well is owed to her positive spirit.

If you look at the report 8 of the 9 yeast and fungal markers listed were elevated, some hundreds of times higher than normal.

It turned out Helen’s kitchen was also very moldy, especially in the fan system in the kitchen. Some of the fungal toxins identified in her OAT test (listed as 2, 3 and 4 on the report) were probably signs of black mould, Aspergillus, which she had been breathing in while cooking.

The markers 6 (Tartaric) and 7 (Arabinose) are the ones that Candida produces.

So Helen had a yeast infection from household mould exposure as well as Candida growing in her gut. All these fungal toxins put a tremendous load on her system.

Other findings from her Organic Acids Test showed her energy producing metabolism was messed up with high levels of lactic acid in her test result, which was causing her muscle aches and low tolerance to exercise.

Other parts of her test identified abnormalities in her mood-related neurotransmitters such as serotonin. Gut infections often cause a drop in serotonin levels, causing a secondary anxiety, and possibly also depression.

Helen’s case gives a clear insight into how gut infections can have metabolic effects, manifesting as many other symptoms seemingly unrelated to the gut.

Metabolic testing takes out the guesswork

The Organic Acid Test was able to help us in the accurate diagnosis for Helen. It is a urine test that provides a snapshot of the metabolism the byproducts the body discards through the urine.

These discarded organic acid molecules can indicate disorders of metabolism including energy production, the presence of yeast (Candida) or bacterial overgrowth in the gut leading to toxicity and many other issues.

As Candida infections can be hard to identify—Helen had no outward signs of yeast infections at all—it is an accurate way to be certain of the issue, since the yeast has to be alive and active to produce the yeast toxins (in case of Candida Tartaric and arabinose are key markers). The same test can also point us to bacterial infections in the gut as well, which were only mildly elevated in Helen’s case.

Abnormally high levels of these intestinal microorganisms can cause or worsen behavior disorders, hyperactivity, depression, attention deficits and concentration issues, muscle pain and some movement disorders, fatigue and immune dysfunction.

Many people with chronic illnesses and neurological disorders often excrete several abnormal organic acids. The cause of these high levels could include: oral antibiotic use, high sugar diets, immune deficiencies, gluten intolerance, and genetic factors.

This one simple urine test can reveal:

  • High levels of intestinal yeast (Candida) overgrowth
  • High levels of bacterial and other toxins from the gut
  • Evaluation integrity of intestinal wall for leaky gut
  • Assessment neuro-transmitter levels relevant to anxiety, addiction or depression
  • Assessment central nervous system function for inflammation
  • Evaluation of energy production by the mitochondria
  • Detect nutritional and antioxidant deficiencies
  • Determine problems in fatty acid metabolism

On the first page of the sample report you will see “Yeast and Fungal Markers” and “Malabsorption and Bacterial Markers” markers.

The sample report there shows a yeast overgrowth problem clearly because of the elevated levels of tartaric and arabinose. Tartaric will cause fatigue and muscle weakness or pain, while arabinose causes attention and concentration issues and interferes with normal brain chemistry affecting the moods.

A patient with a report this could be classified as suffering “Gut and Psychology Syndrome” or GAPS for short. He/she would be put on a low fermentation, low sugar diet along with anti-fungals and probiotics to correct the mood and concentration issues.

Treatment options in naturopathic medicine

If abnormalities are detected using the OAT, treatments can include anti-microbial herbs or medications, or supplements, such as probiotics, vitamins and antioxidants, or dietary modification.

Upon treatment, both the patients and IMI practitioners have reported significant improvement, such as decreased fatigue, regular bowel function, increased energy and alertness, increased concentration, improved verbal skills, less hyperactivity, and decreased abdominal pain.

I recommend the OAT as the initial screening test, especially for the following:

  • Fatigue
  • Anxiety
  • Asperger’s Syndrome
  • Autism Spectrum Disorders
  • Chronic Fatigue
  • Colitis and Crohn’s Disease
  • Depression
  • Fibromyalgia
  • Gastrointestinal Disorders, Irritable Bowel Syndrome, Diarrhea or Constipation
  • Learning Disabilities
  • Movement Disorders – including muscle pain and muscle fatigue
  • Multiple Sclerosis
  • Obsessive Compulsive Disorder
  • Recurrent Infections such as cystitis or sinusitis
  • Tic Disorders and Tourette Syndrome
  • Common symptoms indicating gut infections may include: Gas-bloating, Flatulence, Abdominal discomfort, Diarrhea or constipation, Anal fistula, Steatorrhea or floating smelly stools, Weight loss
  • Features associated with micronutrient deficiencies – needs for extra vitamin B12 and folate are well indicated for example.

A yeast metabolite causes functional Vitamin B deficiencies, affecting the brain, nerves (neurotransmitter production) and energy production. Depletes the cellular defense systems (enzymes such as glutathione and SOD) causing increased and multiple chemical sensitivity. Interferes with normal sugar metabolism.

4-Cresol – Marker for Bacteria Including Selected Clostridia
Indicates a possible overgrowth of intestinal bacteria that are specific p-cresol producers including selected Clostridia. 4-Cresol is a phenolic product poorly metabolized in children with autism. High-potency multi-strain probiotics may help rebalance GI flora.

DHPPA – Marker for Beneficial Bacteria
Harmless or beneficial bacteria mediate the breakdown of chlorogenic acid to 3,4-dihydroxyphenylpropionic acid (DHPPA). High values of DHPPA are associated with increased amounts of bacteria in the gastrointestinal tract.

5-Hydroxyindoleacetic (5-HIAA)
Gives some indication of Serotonin levels in the body

Quinolinic Acid – Marker for Inflammation and Neurotoxicity
This acid derived from the amino acid tryptophan and can be neurotoxic at high levels.

Quinolinic acid can over stimulate nerve cells, causing the cells to die.

Brain toxicity due to this acid has been implicated in Alzheimer’s disease, autism, Huntington’s disease, stroke, dementia, depression, HIV-associated dementia, and schizophrenia.

Quinolinic Acid/5-HIAA Ratio – Marker for Neurotoxicity and Inflammation
A high ratio of quinolinic acid to the metabolite 5-hydoxyindole-acetic acid indicates excessive inflammation, which will age and damage the brain.

High levels of these markers could be due to recurrent infections, including persistent infections in the gut, immune overstimulation, too high tryptophan intake, excessive adrenal production of cortisol (stress), sleep deprivation, and frequent exposure to phthalates (chemical used in plastics and many household items).

Malic Acid – Marker for Mitochondrial Dysfunction
When malic acid is elevated simultaneously with citric, fumaric, and alpha-ketoglutaric acids, it may cause Cytochrome C Oxidase Deficiency, a metabolic disorder disrupting energy production.

Tartaric acid
Tartaric acid and other yeast byproducts are also elevated in urine samples of adults with the disorder fibromyalgia, a debilitating disease associated with muscle and joint pain, depression, foggy thinking, and chronic fatigue. The Tartaric acid made by Candida also has the ability to cause sugar cravings and low blood sugar levels through blocking the Krebbs Cycle for energy production in our cells.

Indicates folate deficiency

Indicates Vitamin B 12 deficiency

If you would to find out whether the OAT is right for your symptoms, please contact IMI’s Integral Health Advisor,, or make an appointment with one of IMI’s Naturopathic Medicine practitioners by calling 2523 7121.

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Organic Acid Test (OAT): Is It Legit or A Hoax?

Organic Acids Test (OAT): Yeast and Bacterial Overgrowth

Organic acid test (OAT) has gained popularity among many functional health experts in recent years.

But do they give more bang for your buck compared to conventional tests ordered by doctors? How well are they backed by science and scientific research? Will an OAT provide valuable insight into how your body is working, or will it just be money down the drain? We’ve done the research — read on to learn what we’ve discovered.

What is the Organic Acid Test?

Organic Acid Test, popularly known as OAT, measures the levels of organic compounds in urine that are produced in the body as a part of many vital biochemical pathways.

A defect in a particular pathway can result in either accumulation or lowered levels of its byproducts. Thus, measuring the levels of these markers can help to identify which metabolic process is compromised.

Abnormal levels of organic acids not only signal issues with the metabolism, but excessive amounts of some organic acids can harm the body, which is why people with inborn metabolic disorders often need lifelong treatment.

Legitimate Use

Doctors will order an organic acids test to check for RARE inborn genetic defects of metabolism, most often in newborns. It’s frequently ordered as a follow-up for a positive newborn screen result, as recommended by American College of Medical Genetics and Genomics [1].

These tests are highly specialized and among the most complex tests performed in many laboratories. Performing the tests and interpreting the results requires highly trained and qualified health practitioners (American Board of Medical Genetics and Genomics or other relevant medical board-certified laboratory director) [1].

Usually, abnormal levels of a single organic acid can point to multiple anomalies. That’s why doctors will use a combination of markers to narrow down the potential root cause. They will focus on the overall pattern, rather than on individual abnormalities [1].

Furthermore, a characteristic abnormal organic acid profile is not always sufficient to establish a diagnosis. Confirmation by other tests is often required [1].

Unsanctioned Use

In recent years, some labs have started offering this test to the general public and many alternative practitioners started recommending it in their practice.

OAT testing has expanded to include “the diagnosis” of non-genetic conditions such as nutritional deficiencies or environmental exposure to toxins, which are then “treated” with supplements.

This type of testing also often includes another category of organic acids that are produced as a result of microbial activity (bacteria and yeast) in the gut that can supposedly uncover gut dysbiosis.

It’s important to know that there isn’t much scientific support for this kind of testing. That’s one of the reasons conventional medicine doesn’t recognize them as useful.

But we didn’t take that at face value. We did the legwork and combed the studies to find out which of these tests have been studied, and whether they were useful and informative. Read more about that below.

What Proponents Say

Abnormal OAT profile has been seen in people with some chronic illnesses (such as diabetes, fatigue, kidney disease) and neurological disorders (such as autism, Alzheimer’s disease, ADHD) [2, 3, 4, 5, 6, 7, 8, 9, 10].

Proponents state that prioritizing the treatment by dietary intervention or tailoring the need for specific nutrients may significantly improve clinical outcomes.

What Skeptics Say

Many skeptics say that OAT is a scam. It will set you back around $250 or more, and you will ly not be any better off for doing it.

They say that there’s no evidence these tests provide any useful information. They can’t be relied upon for the diagnosis of any non-genetic conditions. Furthermore, using them in an unsanctioned way can be misleading.

Are OAT Ranges Legit?

In many cases, ly not.

Many of the markers used in OAT have not been studied well enough to understand what ranges in healthy populations are compared to ranges in those with certain diseases.

Read more about how normal ranges are established here.

Which of The OAT Markers Are Reliable?

To find out which parts of the OAT test can be useful, and which are just nonsense, we delve into the science and look into each of the markers in isolation in the following posts:

We’ll summarize the gist of them here.

Most of these markers are mainly used to diagnose rare genetic disorders, and there’s ly no benefit to testing them for any other reasons.

There are many other tests that doctors can use to evaluate your overall health that are reliable and backed up by plenty of studies and actual science.

Among these markers, there are 3 that doctors may actually use, depending on one’s signs, symptoms, medical history, and other test results. They are:

  • Lactic acid – used to check for disturbances in blood pH (lactic acidosis)
  • Citric acid – used in people with or at risk of kidney stones
  • Ketone bodies – used to check blood sugar control in diabetes or confirm ketosis on keto diets

Nutrient Deficiencies & Methylation

Some of the nutritional markers tested as a part of OAT may point to valid nutrient deficiencies, mainly: methylmalonic acid, pantothenic acid, methylcitric acid, and uracil/thymine.

However, in all of these cases, blood tests are more reliable and your doctor is ly to order them for confirmation.

Detoxification and Oxalates

While testing oxalate is relatively common practice, testing other “detoxification” markers is of rather limited value and unly to be of benefit, unless your doctor is screening for inborn metabolic disorders or you’re exposed to significant amounts of toxic chemicals in your workplace or environment.

Testing neurotransmitter metabolites in urine can’t tell you what’s going on in the brain. Doctors test these metabolites in specific cases to diagnose tumors (of the adrenal gland or carcinoid tumors) or to check for rare genetic disorders.

Apart from that, these metabolites respond to certain diets and may be affected by underlying issues such as inflammation. However, testing them has no clear use or benefit.

Amino acid metabolites are used to help diagnose rare genetic disorders, and don’t really seem to have a purpose beyond that.

Yeast and Bacterial Metabolites

Markers of yeast and bacterial overgrowth are the most exciting part of the organic acid test (OAT). Mainly because we are just beginning to understand our microbiome and the effect it has on our bodies and metabolism. However, this also means that these markers are experimental — no clinical studies have verified or validated their use and their ranges.

While there are studies that have linked most of these markers to yeast and bacterial overgrowth, they are few and small in scale. Much larger and well-designed research is needed to establish how useful and informative testing each of these markers is in the general population.

Many of these markers can increase due to causes other than microbial overgrowth, including certain foods and metabolic disorders. Therefore, results should be interpreted with caution by a qualified medical professional. Your doctor will interpret your results in conjunction with your signs, symptoms, medical history, and other test results, and they will order further tests if needed.

Bottom Line: Is OAT Useful Or A Hoax?

The truth is probably that most people don’t require this test and will not benefit from getting it.

Many of the markers in this test are useless for the majority of people.

Then again, particular markers found in this test are legitimately used to help diagnose some non-genetic conditions. However, you could probably get those markers tested, if needed, for less than 250$.

Keep in mind that:

  • Many organic acids require the collection of 24 hr urine in order to provide accurate information (i.e. OAT test has lower accuracy).
  • Most organic acids are indirect or non-specific markers and can be falsely elevated due to benign conditions. That is why they should never be relied upon in isolation. Doctors will always use a combination of markers to get a picture of the underlying cause.
  • Often, urinary levels do not reflect the levels in tissues. This is especially the case for neurotransmitters metabolites.

If in doubt whether to get this test done, weigh the pros and cons with your doctor.