Organic Acids Test (OAT)


The following is a list of ten descriptions for why the Organic Acids Test from Great Plains Laboratory is worth doing and learning more about:

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The OAT evaluates for various fungal toxins, including specific markers for candida, as well as other fungus such as mold and yeast. Many individuals rely on stool testing for candidiasis diagnosis. However, a stool test is often negative for candida overgrowth detection, while the OAT often detects the presence of candida and yeast toxins (authors experience). The OAT is overall more sensitive for candida analysis because it is detecting chemical production within the digestive system that is reflective of these organism’s metabolic activity, and tissue invasion along the mucosal lining of the gut. The organic acid arabinose, often elevated on the OAT, is linked to this process of mucosal invasion. Some of candida toxins can create problems with brain function including memory, attention, and focus.

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The OAT evaluates for specific toxins related to various clostridia bacteria. Clostridia bacteria such as Clostridia difficile (C. diff.) can lead to digestive problems and poor health (1). For example, certain strains of C. diff. produce virulence factors which cause inflammation, bleeding, and diarrhea within the digestive system. However, there are other clostridia toxins that work outside the digestive system. The main toxins evaluated on the OAT linked to different strains of clostridia are HPHPA and 4-cresol (2). Both HPHPA and 4-cresol can inhibit a dopamine converting enzyme leading to excess dopamine in the brain and nervous system (3).

High dopamine can form toxic compounds that adversely affect brain cells. Long-standing elevation of these dopamine related compounds such as DOPAC (and dopamine-o-quinone, a compound not measured on the OAT) are known to trigger free radical damage within the brain. The elevation of the neurotransmitter dopamine can also cause mood instability, and other cognitive problems. In severe cases, the presence of these clostridia toxins can trigger aggressive and self-injury behavior from high amounts of dopamine. This is a common scenario in special needs individuals such as those with autism. Evaluating for clostridia organic acid toxins is essential for anyone struggling with a developmental disorder, mental health problems, and neurological diseases.

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The information from the OAT helps to prioritize treatment intervention decisions, along with symptoms and clinical history, between candida (fungus) and clostridia (bacteria). Treating for candida alone when clostridia bacteria toxins of HPHPA and 4-cresol are present may lead to significant problems aggravating the digestive system, but also leading to adverse changes in neurochemicals affecting behaviors, cognitive abilities, mood, and mental stability.

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The OAT evaluates for high oxalate (a.k.a. oxalic acid). Oxalate is a compound found in many foods such as nuts (e.g., almonds), fruit (e.g., berries) and certain vegetables (e.g., spinach). Oxalate can also be produced by candida overgrowth, aspergillus mold, as well as certain metabolic imbalances linked to deficiency in oxalate metabolizing enzymes. High oxalate is often associated with joint and muscle pain but can lead to bladder and bowel discomfort as well. Severe cases of oxalate accumulation can cause kidney stones. Oxalate can trap heavy metals such as mercury, lead, and arsenic in the body and lead to mineral imbalances.

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The OAT evaluates for mitochondrial imbalances. The mitochondria are the energy factories of our cells producing large amounts of adenosine triphosphate (ATP). ATP acts as energy currency for our body. Mitochondria are often stressed because of toxins from candida, bacteria, oxalate, heavy metals, and environmental chemicals. Mitochondrial dysfunction is common in many chronic health disorders.

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The OAT evaluates for imbalances in dopamine and norepinephrine. The relationship between these two important brain chemicals is critical for attention, focusing, mood, calmness, and other functions of the nervous system.

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The OAT evaluates for deficiency of excess of serotonin, an important brain chemical for mood, fine and gross motor skills, calmness, and sleep. There are other markers evaluated on the OAT that can indicate toxic stress in the brain and nervous system. One of these potentially toxic compounds is called quinolinic acid (QA). Elevated QA can be toxic in the brain triggering increase receptor activity that allows for increase influx of calcium into a brain cell. This mechanism can lead to a host of cell problems causing or contributing to brain cell death and destruction. For these reasons, it is beneficial to perform an OAT before implementing high dose amino acid L-tryptophan supplementation which is often used to assist with sleep or some mental health disorders.

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The OAT evaluates for two specific chemicals related to folate metabolism. Folate is linked to the methylation cycle that supports the inner workings of the cells related to DNA function and metabolism. Poor folate metabolism can lead to cognitive problems.

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The OAT evaluates for various nutritional markers such as vitamin B6, vitamin B5, vitamin C, CoQ10, as well as N-Acetylcysteine (NAC). NAC is necessary as a precursor for the antioxidant glutathione.

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The OAT evaluates for glutathione deficiency. Glutathione is a powerful antioxidant in our cells and protects against toxicity. The lack of glutathione leads to oxidative stress within the brain and nervous system which causes poor attention, focusing, and overall cognitive challenges. Glutathione deficiency can also compromise immune system health. Glutathione is a necessary compound involved liver detoxification of chemicals.

Detailed Description


The Organic Acids Test (OAT) offers a comprehensive metabolic snapshot of overall health with 76 markers.  It provides an accurate evaluation of intestinal yeast and bacteria. Abnormally high levels of these microorganisms can cause or worsen behavior disorders, hyperactivity, movement disorders, fatigue and immune function. Many people with chronic illnesses and neurological disorders often excrete several abnormal organic acids in their urine. The cause of these high levels could include oral antibiotic use, high sugar diets, immune deficiencies, acquired infections, as well as genetic factors.

Great Plains Labs Organic Acids Test also includes markers for vitamin and mineral levels, oxidative stress, neurotransmitter levels, and is the only OAT to include markers for oxalates, which are highly correlated with many chronic illnesses.

Organic acids are chemical compounds excreted in the urine that are products of metabolism. Metabolism is the sum of chemical reactions in living beings by which the body builds new molecules and breaks down molecules to eliminate waste products and produce energy. Organic acids are organic compounds that are acidic.

If abnormalities are detected using the OAT, treatments can include supplements, such as vitamins and antioxidants, or dietary modification. Upon treatment, patients and 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. The OAT is strongly recommended as the initial screening test.



Almost all organic acids used for human testing are measured by a combination of gas or liquid chromatography linked with mass spectrometry. Organic acids are most commonly analyzed in urine because they are not extensively reabsorbed in the kidney tubules after glomerular filtration. Thus, organic acids in urine are often present at 100 times their concentration in the blood serum and thus are more readily detected in urine. This is why organic acids are rarely tested in blood or serum. The number of organic acids found in urine is enormous. Over 1,000 different organic acids have been detected in urine since this kind of testing started.


Many genetic disorders are caused by the production of an inefficient enzyme that reacts at a slower than usual rate, resulting in an accumulation of a metabolic intermediate. More than 50 phenotypically different organic acidemias (a group of disorders characterized by increased excretion of acids in the urine) are now known since the oldest known disease, isovaleric aci­demia, was described in 1966. An organic acid is any compound that generates protons at the prevailing pH of human blood. Although some organic acidemias result in lowered blood pH, other organic acidemias are associated with organic acids that are relatively weak and do not typically cause acidosis. Organic acidemias are disorders of intermediary metabolism that lead to the accumulation of toxic compounds that derange multiple intracellular biochemical pathways including glucose catabolism (glycolysis), glucose synthesis (gluconeogenesis), amino acid and ammonia metabolism, purine and pyrimidine metabolism, and fat metabolism. The accumulation of an organic acid in cells and fluids (plasma, cerebrospinal fluid, or urine) leads to a disease called organic acidemia or organic aciduria.

Clinical presentations of organic acidemias vary widely and may include failure to thrive, intellectual development disorders, hypo- or hyperglycemia, encephalopathy, lethargy, hyperactivity, seizures, dermatitis, dysmorphic facial features, microcephaly, macrocephaly, anemia and/or immune deficiency with frequent infections, ketosis and/or lactic acidosis, hearing, speech, or visual impairment, peripheral neuropathy, sudden cardiorespiratory arrest, nau­sea and coma. Many organic acidemias are associated with slight to marked increases in plasma ammonia. Some organic acidemias may be chronic and present in the first few days of life. In others, such as medium-chain acyl dehydrogenase deficiency, a child might appear completely normal until a potentially fatal episode of cardiorespiratory arrest.

Many other non-genetic factors can also alter human metabolism. Toxic amounts of the drug acetaminophen and other toxic chemicals can use up a key molecule, glutathione, that helps the body detoxify, leading to the overproduction of the organic acid pyroglutamic acid. Tumors of the adrenal gland called pheochromacytomas can cause the overproduction of the neurotransmitter epinephrine, resulting in marked increases in its metabolite, vanillylmandelic acid (VMA). Genetic diseases of the mitochondria, the cell’s energy source, as well as toxic chemicals that disrupt mitochondrial function cause elevation of succinic acid.  Succinic acid is a key intermediate of both the Kreb’s cycle and the electron transport chain that generates adenosine triphosphate (ATP), the currency for most of the body’s energy transactions.

A number of organic acids directly or indirectly indicate deficiencies of critical vitamins such as vitamin B12, pantothenic acid, biotin, and others. One of the most important uses of the organic acids test is as an indicator of dysbiosis, an abnormal overgrowth of yeast and bacteria in the intestinal tract. Some of these bacterial byproducts from the intestine enter the bloodstream and may alter the metabolism of neurotransmitters such as dopamine.



 The Organic Acids Test by The Great Plains Laboratory is the only OAT on the market that evaluates levels of oxalates in urine. Oxalate (and its acid form, oxalic acid), is an organic acid that is primarily derived from three sources: the diet, fungus (such as Aspergillus and Penicillium), possibly Candida, and also human metabolism. Oxalic acid is the most acidic organic acid in body fluids and is used commercially to remove rust from car radiators. Antifreeze (ethylene glycol) is toxic primarily because it is converted to oxalate in the body. Two different types of genetic diseases are known in which oxalates are high in the urine, hyperoxalurias type I and type II, which can also be determined from the Organic Acids Test.

High Oxalate Food List

Foods especially high in oxalates are often foods thought to be otherwise healthy, including spinach, beets, chocolate, peanuts, wheat bran, tea, cashews, pecans, almonds, berries, and many others. People now frequently consume “green smoothies” in an effort to eat “clean” and get healthy, however, they may actually be sabotaging their health. The most common components of green smoothies are spinach, kale, Swiss chard, and arugula, all of which are loaded with oxalates. These smoothies also often contain berries or almonds, which have high amounts of oxalates as well. Oxalates are not found in meat or fish at significant concentrations. Daily adult oxalate intake is usually 80-120 mg/d. A single green smoothie with two cups of spinach contains about 1,500 mg of oxalate, a potentially lethal dose.

External sources of oxalates include ethylene glycol, the main component of antifreeze. Antifreeze is toxic mainly because of the oxalates formed from it. In addition, some foods also contain small amounts of ethylene glycol. Vitamin C (ascorbic acid or ascorbate) can be converted to oxalates but the biochemical conversion system is saturated at low levels of vitamin C so that no additional oxalate is formed until very large doses (greater than 4 g per day) are consumed. The high correlation between arabinose and oxalates indicate that intestinal yeast/fungal overgrowth is likely the main cause for elevated oxalates in the autistic spectrum population. The deposition of oxalates in critical tissues such as brain and blood vessels, the oxidative damage caused by oxalate salts, and the deposition of oxalate mercury complexes in the tissues.